Is NAT can provide some kind of protection?
We have wide range of Public IP addresses, I tried to assign public ip directly to a server behined firewall( in DMZ), but I have been resisted. Security guy told me is not correct to assign public ip to a server, it should have private ip for security reasons. Is it true that NAT can provide more security? Thanks, Tarig Yassin Ahmed
Re: Is NAT can provide some kind of protection?
On 21/03/2007 09:41, Tarig Ahmed wrote: Is it true that NAT can provide more security? No. Your security person is probably confusing NAT with firewalling, as NAT devices will intrinsically do firewalling of various forms, sometimes stateful, sometimes not. Stateful firewalling _may_ provide more security in some situations for low bandwidth applications, at least before you're hit by a DoS attack; for high bandwidth applications, stateful firewalling is usually a complete waste of time. Your security guy will probably say that a private IP address will give better protection because it's not reachable on the internet. But the reality is if you have 1:1 NAT to a server port, then you have reachability and his argument becomes substantially invalid. Most security problems are going to be related to poor coding anyway (XSS, improper data validation, etc), rather than port reachability, which is easy to fix. Unfortunately, many security people from large organisations do not appreciate these arguments, but instead write their own and other peoples' opinions down and call them policy. Changing policy can be difficult. Nick
Re: Is NAT can provide some kind of protection?
In fact our firewall is stateful. This is why I thought, we no need to Nat at least our servers. Tarig Yassin Ahmed On Jan 12, 2011, at 4:59 PM, Nick Hilliard n...@foobar.org wrote: On 21/03/2007 09:41, Tarig Ahmed wrote: Is it true that NAT can provide more security? No. Your security person is probably confusing NAT with firewalling, as NAT devices will intrinsically do firewalling of various forms, sometimes stateful, sometimes not. Stateful firewalling _may_ provide more security in some situations for low bandwidth applications, at least before you're hit by a DoS attack; for high bandwidth applications, stateful firewalling is usually a complete waste of time. Your security guy will probably say that a private IP address will give better protection because it's not reachable on the internet. But the reality is if you have 1:1 NAT to a server port, then you have reachability and his argument becomes substantially invalid. Most security problems are going to be related to poor coding anyway (XSS, improper data validation, etc), rather than port reachability, which is easy to fix. Unfortunately, many security people from large organisations do not appreciate these arguments, but instead write their own and other peoples' opinions down and call them policy. Changing policy can be difficult. Nick
Cisco Sanitization
Hey all! I'm currently creating a sanitization guide for all my hardware. When I got to my Cisco devices I noticed there are numerous ways to reset them back to the default and clear the NVRAM. Does anyone have a guide that includes sanitization information for all Cisco devices(at least switches, routers, IDS's, and ASA 5500 Series) so I don't have to recreate the wheel? Thanks, Tim
Fw: Cisco Sanitization
V - Original Message - From: Greg Whynott Sent: Wednesday, January 12, 2011 09:46 AM To: 'timothy.gr...@mantech.com' timothy.gr...@mantech.com Subject: Re: Cisco Sanitization Replace the flash cards. If you are really concerned about information being disclosed, formatting/deleting files will not destroy the data and it probably can be recovered. Or take the flash cards and scrub them from a pc. G - Original Message - From: Green, Timothy [mailto:timothy.gr...@mantech.com] Sent: Wednesday, January 12, 2011 09:41 AM To: nanog@nanog.org nanog@nanog.org Subject: Cisco Sanitization Hey all! I'm currently creating a sanitization guide for all my hardware. When I got to my Cisco devices I noticed there are numerous ways to reset them back to the default and clear the NVRAM. Does anyone have a guide that includes sanitization information for all Cisco devices(at least switches, routers, IDS's, and ASA 5500 Series) so I don't have to recreate the wheel? Thanks, Tim -- This message and any attachments may contain confidential and/or privileged information for the sole use of the intended recipient. Any review or distribution by anyone other than the person for whom it was originally intended is strictly prohibited. If you have received this message in error, please contact the sender and delete all copies. Opinions, conclusions or other information contained in this message may not be that of the organization.
Re: Is NAT can provide some kind of protection?
On 3/21/2007 6:25 AM, Tarig Ahmed wrote: In fact our firewall is stateful. This is why I thought, we no need to Nat at least our servers. Tarig Yassin Ahmed On Jan 12, 2011, at 4:59 PM, Nick Hilliard n...@foobar.org wrote: On 21/03/2007 09:41, Tarig Ahmed wrote: Is it true that NAT can provide more security? No. Your security person is probably confusing NAT with firewalling, as NAT devices will intrinsically do firewalling of various forms, sometimes stateful, sometimes not. Stateful firewalling _may_ provide more security in some situations for low bandwidth applications, at least before you're hit by a DoS attack; for high bandwidth applications, stateful firewalling is usually a complete waste of time. Your security guy will probably say that a private IP address will give better protection because it's not reachable on the internet. But the reality is if you have 1:1 NAT to a server port, then you have reachability and his argument becomes substantially invalid. Most security problems are going to be related to poor coding anyway (XSS, improper data validation, etc), rather than port reachability, which is easy to fix. Unfortunately, many security people from large organisations do not appreciate these arguments, but instead write their own and other peoples' opinions down and call them policy. Changing policy can be difficult. Nick Tarig is sending email from the past. Spooky.
Re: Cisco Sanitization
Really the only way to to clean devices with flash is to destroy the flash. At a very least you'll need to reflash them with the current OS. Here is a copy of the DOD Guidelines for every thing... http://it.ouhsc.edu/policies/documents/infosecurity/DoD_5220.pdf The flash answer is to use something to write to EVERY address, then erase, or just pulverize it. johno On Jan 12, 2011, at 9:41 AM, Green, Timothy wrote: Hey all! I'm currently creating a sanitization guide for all my hardware. When I got to my Cisco devices I noticed there are numerous ways to reset them back to the default and clear the NVRAM. Does anyone have a guide that includes sanitization information for all Cisco devices(at least switches, routers, IDS's, and ASA 5500 Series) so I don't have to recreate the wheel? Thanks, Tim
Re: Is NAT can provide some kind of protection?
On 01/12/2011 02:59 PM, Nick Hilliard wrote: On 21/03/2007 09:41, Tarig Ahmed wrote: Is it true that NAT can provide more security? No. [snip] Your security guy will probably say that a private IP address will give better protection because it's not reachable on the internet. But the reality is if you have 1:1 NAT to a server port, then you have reachability and his argument becomes substantially invalid. This setup will provide *less* security. Apart from the DoS scenario, should your public facing server get compromised, you have given easy access to your private infrastructure. -Lorand Jakab
Re: Fw: Cisco Sanitization
Or why not just paste a REALLY large bogus config in there to max-out the NVRAM chip? That's the one that's harder to move to a PC. On the flash, moving to a PC is easier (at least if we're talking about newer devices using PCMCIA!) :) I suppose that everyone's level of detail is somewhat equivalent to the level of paranoia or level of desired protection along the way! Scott On 1/12/11 9:48 AM, Greg Whynott wrote: V - Original Message - From: Greg Whynott Sent: Wednesday, January 12, 2011 09:46 AM To: 'timothy.gr...@mantech.com' timothy.gr...@mantech.com Subject: Re: Cisco Sanitization Replace the flash cards. If you are really concerned about information being disclosed, formatting/deleting files will not destroy the data and it probably can be recovered. Or take the flash cards and scrub them from a pc. G - Original Message - From: Green, Timothy [mailto:timothy.gr...@mantech.com] Sent: Wednesday, January 12, 2011 09:41 AM To: nanog@nanog.org nanog@nanog.org Subject: Cisco Sanitization Hey all! I'm currently creating a sanitization guide for all my hardware. When I got to my Cisco devices I noticed there are numerous ways to reset them back to the default and clear the NVRAM. Does anyone have a guide that includes sanitization information for all Cisco devices(at least switches, routers, IDS's, and ASA 5500 Series) so I don't have to recreate the wheel? Thanks, Tim -- This message and any attachments may contain confidential and/or privileged information for the sole use of the intended recipient. Any review or distribution by anyone other than the person for whom it was originally intended is strictly prohibited. If you have received this message in error, please contact the sender and delete all copies. Opinions, conclusions or other information contained in this message may not be that of the organization.
Re: Is NAT can provide some kind of protection?
+1 on Nick's comment. If you're doing 1:1 NAT or port forwarding your server is still public facing. If your firewall is merely stateful and not deep packet inspecting all it's doing is seeing is that the statefulness of the connection meets it's requirements. You could have that and still have all kinds of naughtiness going on. Greg On Mar 21, 2007, at 6:25 AM, Tarig Ahmed wrote: In fact our firewall is stateful. This is why I thought, we no need to Nat at least our servers. Tarig Yassin Ahmed On Jan 12, 2011, at 4:59 PM, Nick Hilliard n...@foobar.org wrote: On 21/03/2007 09:41, Tarig Ahmed wrote: Is it true that NAT can provide more security? No. Your security person is probably confusing NAT with firewalling, as NAT devices will intrinsically do firewalling of various forms, sometimes stateful, sometimes not. Stateful firewalling _may_ provide more security in some situations for low bandwidth applications, at least before you're hit by a DoS attack; for high bandwidth applications, stateful firewalling is usually a complete waste of time. Your security guy will probably say that a private IP address will give better protection because it's not reachable on the internet. But the reality is if you have 1:1 NAT to a server port, then you have reachability and his argument becomes substantially invalid. Most security problems are going to be related to poor coding anyway (XSS, improper data validation, etc), rather than port reachability, which is easy to fix. Unfortunately, many security people from large organisations do not appreciate these arguments, but instead write their own and other peoples' opinions down and call them policy. Changing policy can be difficult. Nick
Re: Cisco Sanitization
list, sorry for this but this is getting a little annoying. I've tried sending Randy email without luck.. think i'm black listed by his kit, so if someone would kindly forward this to him… Randy, I'm not trying to be difficult or annoy you. Please stop sending me this email which is considered spam by most. 30 messages of with the same unsolicited content is spam. I understand you do not like a signature which 'seems' to contain legal jargon. I understand you know everything about my environment and the policies of my company which I do not define. I undertand you would like me to use gmail and violate my company policy. I don't expect _anything_ from you, but i would appreciate it if you could take some of your apparent talent and put some logic into your proc mail recipe or whatever it is you use to to generate this message. avoid responding with this spam message every time i post to a list you happen to be on. The email was not directed to you directly. should take about someone with your skill set very little effort. thank you. greg On Jan 12, 2011, at 10:50 AM, Randy Bush wrote: you have sent a message to me which seems to contain a legal warning on who can read it, or how it may be distributed, or whether it may be archived, etc. i do not accept such email. my mail user agent detected a legal notice when i was opening your mail, and automatically deleted it. so do not expect further response. yes, i know your mail environment automatically added the legal notice. well, my mail environment automatically detected it, deleted it, and sent this message to you. so don't expect a lot of sympathy. and if you choose to work for some enterprise clueless enough to think that they can force this silliness on the world, use gmail, hotmail, ... randy -- This message and any attachments may contain confidential and/or privileged information for the sole use of the intended recipient. Any review or distribution by anyone other than the person for whom it was originally intended is strictly prohibited. If you have received this message in error, please contact the sender and delete all copies. Opinions, conclusions or other information contained in this message may not be that of the organization.
RE: Is NAT can provide some kind of protection?
Is it true that NAT can provide more security? Thanks, Tarig Yassin Ahmed You are going to get different answers from different people. In and of itself it doesn't provide security but it does place one more layer of difficulty in getting at your internal machines. On the other hand, NAT makes many things a lot more difficult than they need to be in many cases and outright breaks some protocols (SCTP, for example). On one hand, yes, it can make direct addressing of your servers more difficult but doesn't guarantee anything. RFC1918 routes should not be routed over the internet but sometimes people leak them and sometimes people accept such leaked routes. So there is the possibility that someone could see a route to your RFC1918 space. But on the other hand, even if you did leak the route, the odds of someone being able to reliably connect to your network is pretty low because if they are accepting such leaked routes from you, they might be accepting them from others, too. And your upstream's peers are probably filtering 1918 space and most likely route traffic destined to rfc1918 space they aren't using to a black hole. But your security person needs to shift their thinking because the purpose of NAT and private addressing is to conserve IP address, not to provide security. With IPv6, the concept of NAT goes away. You servers will need public IP addresses if they are going to transact information across the Internet. So the security concerns of public IP space are moot when it comes to IPv6.
Re: Cisco Sanitization
On 1/12/2011 8:04 AM, Greg Whynott wrote: list, sorry for this but this is getting a little annoying. I've tried sending Randy email without luck.. think i'm black listed by his kit, so if someone would kindly forward this to him… Well, here it is. Perhaps you might consider getting a gmail or other account, and posting on NANOG from there. Either that, or filter Randy out. Personally, I find those silly disclaimers annoying, but am far too lazy to set up a script such as Randy has. You don't want to be annoyed? Lose the disclaimer, use a different email address, or filter Randy out. This is NOT the first time you've complained about this (although we know, for sure, that Randy is going to send this off, automagically, to anyone that has the silly disclaimer thing going for them). Get over it. Please don't post on this again. Thanks in advance. -- Amor fati. Vale. (Seneca)
Re: Cisco Sanitization
my bad list,i'll stay on topic in the future and ensure i keep personal messages out of here and your inbox. bad bad greg… interesting how brain dead and un respectful i am till sufficiently caffeinated. On Jan 12, 2011, at 11:19 AM, Lynda wrote: On 1/12/2011 8:04 AM, Greg Whynott wrote: list, sorry for this but this is getting a little annoying. I've tried sending Randy email without luck.. think i'm black listed by his kit, so if someone would kindly forward this to him… Well, here it is. Perhaps you might consider getting a gmail or other account, and posting on NANOG from there. Either that, or filter Randy out. Personally, I find those silly disclaimers annoying, but am far too lazy to set up a script such as Randy has. You don't want to be annoyed? Lose the disclaimer, use a different email address, or filter Randy out. This is NOT the first time you've complained about this (although we know, for sure, that Randy is going to send this off, automagically, to anyone that has the silly disclaimer thing going for them). Get over it. Please don't post on this again. Thanks in advance. -- Amor fati. Vale. (Seneca) -- This message and any attachments may contain confidential and/or privileged information for the sole use of the intended recipient. Any review or distribution by anyone other than the person for whom it was originally intended is strictly prohibited. If you have received this message in error, please contact the sender and delete all copies. Opinions, conclusions or other information contained in this message may not be that of the organization.
Re: Is NAT can provide some kind of protection?
On 12/01/2011 01:17 p.m., George Bonser wrote: But your security person needs to shift their thinking because the purpose of NAT and private addressing is to conserve IP address, not to provide security. With IPv6, the concept of NAT goes away. You have heard about NAT66, right? Thanks, -- Fernando Gont e-mail: ferna...@gont.com.ar || fg...@acm.org PGP Fingerprint: 7809 84F5 322E 45C7 F1C9 3945 96EE A9EF D076 FFF1
Re: IPv6 - real vs theoretical problems
On 01/11/2011 01:31 PM, Owen DeLong wrote: It's not about the number of devices. That's IPv4-think. It's about the number of segments. I see a world where each home-entertainment cluster would be a separate segment (today, few things use IP, but, future HE solutions will include Monitors, Amps, Blu-Ray players, and other Media gateways that ALL have ethernet ports for control and software update). Your future is now, Owen. I have four network devices at my primary television -- the TV itself, TiVo, PS3, and Wii (using the wired adapter). All told, I have seven networked home entertainment devices in my house, with another (Blu-Ray player) likely coming soon. I feel confident in saying that my use case isn't unusual these days. While a lot of the scalability concerns are blown off as not applying to typical consumers, we're quickly getting to the point where your average joe IS somewhat likely to have different classes of devices that might benefit from being on separate subnets. Jima
Re: Is NAT can provide some kind of protection?
Tell your security guy he should be looking for another job. On 21/03/2007, at 8:41 PM, Tarig Ahmed tariq198...@hotmail.com wrote: We have wide range of Public IP addresses, I tried to assign public ip directly to a server behined firewall( in DMZ), but I have been resisted. Security guy told me is not correct to assign public ip to a server, it should have private ip for security reasons. Is it true that NAT can provide more security? Thanks, Tarig Yassin Ahmed
RE: Is NAT can provide some kind of protection?
-Original Message- From: Fernando Gont [mailto:fernando.gont.netbook@gmail.com] On Behalf Of Fernando Gont Sent: Wednesday, January 12, 2011 8:54 AM To: George Bonser Cc: Tarig Ahmed; nanog@nanog.org Subject: Re: Is NAT can provide some kind of protection? On 12/01/2011 01:17 p.m., George Bonser wrote: But your security person needs to shift their thinking because the purpose of NAT and private addressing is to conserve IP address, not to provide security. With IPv6, the concept of NAT goes away. You have heard about NAT66, right? Thanks, -- Fernando Gont e-mail: ferna...@gont.com.ar || fg...@acm.org PGP Fingerprint: 7809 84F5 322E 45C7 F1C9 3945 96EE A9EF D076 FFF1 Oh, yeah. But NAT66 does not provide the security aspect of PAT with V4. It is just a straight static NAT. So each of your machines is still directly addressable from the Internet. With v4 PAT, you can not be sure which address/port on the external IP maps to which address/port on the inside IP at any given moment and PAT is stateful in that an outbound packet is required to start the mapping. NAT66 is just straight static NAT that maps one prefix to a different prefix.
Re: Is NAT can provide some kind of protection?
On Wed, Mar 21, 2007 at 5:41 AM, Tarig Ahmed tariq198...@hotmail.com wrote: We have wide range of Public IP addresses, I tried to assign public ip directly to a server behined firewall( in DMZ), but I have been resisted. Security guy told me is not correct to assign public ip to a server, it should have private ip for security reasons. Is it true that NAT can provide more security? Hi Tarig, Yes NAT can provide more security, but not in the particular scenario you described. In your scenario, the firewall knows how to map incoming connections for the public address to your server's private address, so you won't see any benefit from NAT versus a merely stateful firewall -- a connection request will either get through the filter or it won't. If it gets through, the firewall knows where to send it. On the other hand, the use of any kind of stateful firewall (most of what we refer to as NAT firewalls keep per-connection state) increases your vulnerability to denial of services attacks: folks DOSing you can target both the server and the firewall's state table. So the use of NAT there is potentially counterproductive. In a client (rather than server) scenario, the picture is different. Depending on the specific NAT technology in use, the firewall may be incapable of selecting a target for unsolicited communications inbound from the public Internet. In fact, it may be theoretically impossible for it to do so. In those scenarios, the presence of NAT in the equation makes a large class of direct attacks on the interior host impractical, requiring the attacker to fall back on other methods like attempting to breach the firewall itself or indirectly polluting the responses to communication initiated by the internal host. In both cases there's a larger question: security value. The value of a security measure is the damage it prevents (risk times impact) minus the damage it causes (system usability, capability). NAT generally causes more damage than packet filters and other lighter-duty security measures. Look for an appropriate improvement in system security to counterbalance that damage. If you don't find it then don't use NAT. Regards, Bill Herrin -- William D. Herrin her...@dirtside.com b...@herrin.us 3005 Crane Dr. .. Web: http://bill.herrin.us/ Falls Church, VA 22042-3004
Re: Is NAT can provide some kind of protection?
On 1/12/2011 11:01 AM, George Bonser wrote: NAT66 is just straight static NAT that maps one prefix to a different prefix. I'd eat a hat if a vendor didn't implement a PAT equivalent. It's demanded too much. There is money for it, so it will be there. Jack
Re: Is NAT can provide some kind of protection?
On 3/21/07 2:41 AM, Tarig Ahmed wrote: Is it true that NAT can provide more security? No. However, some things like PCI compliance require NAT, likely because of the NAT = super hacker firewall concept. ~Seth
Re: Is NAT can provide some kind of protection?
On Wed, 12 Jan 2011 16:01:15 +0100, =?ISO-8859-1?Q?Lor=E1nd_Jakab?= said: This setup will provide *less* security. Apart from the DoS scenario, should your public facing server get compromised, you have given easy access to your private infrastructure. If a public server behind a NAT gets whacked via a php vulnerability, you've *still* given away access to everything behind the NAT that server can reach. pgpRxtBD0fIre.pgp Description: PGP signature
RE: Is NAT can provide some kind of protection?
I'd eat a hat if a vendor didn't implement a PAT equivalent. It's demanded too much. There is money for it, so it will be there. Jack Yeah, I think you are right. But in really thinking about it, I wonder why. The whole point of PAT was address conservation. You don't need that with v6. All you need to do with v6 is basically have what amounts to a firewall in transparent mode in the line and doesn't let a packet in (except where explicitly configure to) unless it is associated with a packet that went out. PAT makes little sense to me for v6, but I suspect you are correct. In addition, we are putting the fire suit on each host in addition to the firewall. Kernel firewall rules on each host for the *nix boxen.
Re: Is NAT can provide some kind of protection?
On 1/12/2011 11:16 AM, valdis.kletni...@vt.edu wrote: 140 million compromised PC's, most of them behind a NAT, can't be wrong. :) And yet blaster type worms are less common now, and I still get the occasional reinfection reported where a computer shop installs XP pre-patch with a public IP. A simple stateful firewall or NAT router would stop that and allow them to finish patching the OS. There is always a new attack vector. Jack
World IPv6 Day
From http://www.networkworld.com/news/2011/011211-world-ipv6-day.html Several of the Internet's most popular Web sites - including Facebook, Google and Yahoo - have agreed to participate in the first global-scale trial of IPv6, the long-anticipated upgrade to the Internet's main communications protocol known as IPv4. The trial — dubbed World IPv6 Day — requires participants to support native IPv6 traffic on their main Web sites on June 8, 2011. Leading content delivery networks Akamai and Limelight Networks also committed to the IPv6 trial, which is being sponsored by the Internet Society. [...] Scott.
Re: IPv6 - real vs theoretical problems
At 11:59 AM 1/12/2011, Jim postulated wrote: On 01/11/2011 01:31 PM, Owen DeLong wrote: It's not about the number of devices. That's IPv4-think. It's about the number of segments. I see a world where each home-entertainment cluster would be a separate segment (today, few things use IP, but, future HE solutions will include Monitors, Amps, Blu-Ray players, and other Media gateways that ALL have ethernet ports for control and software update). Your future is now, Owen. I have four network devices at my primary television -- the TV itself, TiVo, PS3, and Wii (using the wired adapter). All told, I have seven networked home entertainment devices in my house, with another (Blu-Ray player) likely coming soon. I feel confident in saying that my use case isn't unusual these days. While a lot of the scalability concerns are blown off as not applying to typical consumers, we're quickly getting to the point where your average joe IS somewhat likely to have different classes of devices that might benefit from being on separate subnets. Jima I helped a friend setup his home network recently. He is using an old Linksys Router with no v6 support. I like to be conservative and only allocate what might be needed ... part of my Defense in Depth strategy to provide some layer of security with NAT (yes, I know - my security by obscurity is to use something from 172.16) and a limited amount of addresses to allocate (not to mention WPA2 - he had default no security when I first got there). Used to be a /29 would be sufficient for any home. But, before I knew it, he had a wireless printer, laptop, and 4 iPhones all needing the new wireless passphrase to connect, plus he was anticipating 2 more laptops (one each for his children - to whom 2 of the iPhones belonged), and addresses set aside for guests and the occasional business visitor (he works from home). I left him configured with a /28, and told him to call me if he anticipated more. As a side security note - we lost the laptop on the new secured network before I tracked down that it had automatically logged in to his neighbor's (also unprotected) network on reboot. Ted
Re: Is NAT can provide some kind of protection?
On 1/12/2011 11:21 AM, George Bonser wrote: PAT makes little sense to me for v6, but I suspect you are correct. In addition, we are putting the fire suit on each host in addition to the firewall. Kernel firewall rules on each host for the *nix boxen. As my corp IT guy put it to me, PAT forces a routing disconnect between internal and external. There is no way to reach the hosts without the firewall performing it's NAT function. Given that the internal is exclusively PAT, the DMZ is public with stateful/proxy, this provides protection for the internal network while limiting the dmz exposure. The argument everyone makes is that a stateful firewall defaults to deny. However, a single mistake prior to the deny allows traffic in. The only equivalent in a PAT scenario is to screw up port forwarding which would cause a single host to expose a single port unknowingly per mistake (which said port/host combo may not be vulnerable). In a stateful firewall, a screw up could expose all ports on a host or multiple hosts in a single mistake. Then there are the firewall software bugs. In PAT, such bugs don't suddenly expose all your hosts behind the firewall for direct communication from the outside world. In v6 stateful firewall, such a bug could allow circumvention of the entire firewall ruleset and the hosts would be directly addressable from the outside. PAT offers the smallest of security safeguards. However, many corp IT personnel feel more secure having that small safeguard in place along with the many other safeguards they deploy. In a corporate environment where they often love to break everything and anything, I don't blame them. Then we go to the educational sector, where the admins often prefer as much openness as possible. In their case, they will prefer to do away with PAT. Jack
RE: Is NAT can provide some kind of protection?
And yet blaster type worms are less common now, and I still get the occasional reinfection reported where a computer shop installs XP pre-patch with a public IP. A simple stateful firewall or NAT router would stop that and allow them to finish patching the OS. There is always a new attack vector. Jack I'd argue that the above has everything to do with firewalling, and nothing to do with NAT. Slightly OT: It boggles the mind a bit when I find desktop shops -not- using imaging. I would think most people would prefer not to stare at OS install screens - and when you can blast out a fully patched XP image easily in sub-10 minutes, the ROI is staggering. Nathan
Re: Is NAT can provide some kind of protection?
On Wed, Jan 12, 2011 at 9:36 AM, Jack Bates jba...@brightok.net wrote: As my corp IT guy put it to me, PAT forces a routing disconnect between internal and external. There is no way to reach the hosts without the firewall performing it's NAT function. But that's not true. If you have NAT, without a firewall, I can access your internal hosts (by addressing their RFC 1918 address) because you'll be leaking your RFC 1918 addresses in and out. Granted, I might have to be in your immediate upstream, but it can be done. So at best, all it does is limit how many hops away I need to be from you to attack you. Some benefit? Yes. Enough benefit to be worth the trouble? I personally am not convinced. Considering the amount of people who mistake the amount of security NAT provides, we're probably better off without it to remove that false sense of security.
Re: Is NAT can provide some kind of protection?
On 1/12/2011 11:52 AM, Nathan Eisenberg wrote: I'd argue that the above has everything to do with firewalling, and nothing to do with NAT. I agree, but both effectively handle the job. My point is that just because we have lots of infections behind NAT, doesn't mean that NAT (or a firewall) doesn't still serve a purpose. Slightly OT: It boggles the mind a bit when I find desktop shops -not- using imaging. I would think most people would prefer not to stare at OS install screens - and when you can blast out a fully patched XP image easily in sub-10 minutes, the ROI is staggering. Hardware drivers? Jack
Re: Is NAT can provide some kind of protection?
On 1/12/2011 11:57 AM, Steven Kurylo wrote: Some benefit? Yes. Enough benefit to be worth the trouble? I personally am not convinced. Some people believe it is. Who am I to tell them how to run their network? They block facebook and yahoo. I, unfortunately, can't. :) Considering the amount of people who mistake the amount of security NAT provides, we're probably better off without it to remove that false sense of security. People will then have a false sense of security with stateful firewalls that perform no better than NAT, just without the address translation. The type of stateful firewall with or without address translation will not suddenly make people become wiser and implement better security policies. Vendors will always make a cheap setup which people will use and consider themselves secure. Jack
Re: Cisco Sanitization
On Wed, 12 Jan 2011, Lynda wrote: On 1/12/2011 8:04 AM, Greg Whynott wrote: list, sorry for this but this is getting a little annoying. I've tried sending Randy email without luck.. think i'm black listed by his kit, so if someone would kindly forward this to him? Well, here it is. Perhaps you might consider getting a gmail or other account, and posting on NANOG from there. Either that, or filter Randy out. Personally, I find those silly disclaimers annoying, but am far too lazy to set up a script such as Randy has. You don't want to be annoyed? Lose the disclaimer, use a different email address, or filter Randy out. This is NOT the first time you've complained about this (although we know, for sure, that Randy is going to send this off, automagically, to anyone that has the silly disclaimer thing going for them). Get over it. Please don't post on this again. Thanks in advance. While I agree that the disclaimers are annoying, I also recognize that: 1. Many companies have policies that require them to append those disclaimers to every outgoing email message, and the people who post to NANOG often don't have any control over that policy. Debating on this list whether those policies are right or wrong really isn't constructive. 2. Some companies have very strict policies against unauthorized surfing on company time, and checking a gmail account could fall under their definition of unauthorized surfing, even if the purpose of checking said gmail account is to try to resolve a work issue without offending someone's procmail filters with your company's auto-disclaimer. Debating on this list whether those policies are right or wrong really isn't constructive either. That said, sending the You sent me a message with a disclaimer that I do not accept and have thrown in the bitbucket response back to NANOG, for the enjoyment of the other 10,000+ people on the list is even more annoying This will be my only post to this particular tangent of the original thread. jms
Re: Cisco Sanitization
Well, here it is. Perhaps you might consider getting a gmail or other account, and posting on NANOG from there. Either that, or filter Randy out. Personally, I find those silly disclaimers annoying, but am far too lazy to set up a script such as Randy has. disclaimers used to be against nanog list policy. dunno about now. but whomever does not have much sympathy from me. randy
Re: Is NAT can provide some kind of protection?
On Jan 12, 2011, at 8:54 AM, Fernando Gont wrote: On 12/01/2011 01:17 p.m., George Bonser wrote: But your security person needs to shift their thinking because the purpose of NAT and private addressing is to conserve IP address, not to provide security. With IPv6, the concept of NAT goes away. You have heard about NAT66, right? Yes... Hopefully it was just a bad dream. NATing IPv6 doesn't do anything good. There's no benefit, only cost. Owen
Re: World IPv6 Day
the first global-scale trial of IPv6, the long-anticipated upgrade to the Internet's main communications protocol known as IPv4. this phrasing is both amusing and deeply sad. amusing because many folk have been running ipv6 globaly for over a decade. deeply sad because this is taken to be shiny and new as we approach the end of the iana ipv4 free pool. what have people been smoking? randy
Re: Is NAT can provide some kind of protection?
On Jan 12, 2011, at 9:07 AM, Jack Bates wrote: On 1/12/2011 11:01 AM, George Bonser wrote: NAT66 is just straight static NAT that maps one prefix to a different prefix. I'd eat a hat if a vendor didn't implement a PAT equivalent. It's demanded too much. There is money for it, so it will be there. Jack Fortunately, so far, it isn't. Hopefully we can cure the demand through education instead of acquiescence and profiteering. Owen
Re: Is NAT can provide some kind of protection?
On Jan 12, 2011, at 9:04 AM, William Herrin wrote: On Wed, Mar 21, 2007 at 5:41 AM, Tarig Ahmed tariq198...@hotmail.com wrote: We have wide range of Public IP addresses, I tried to assign public ip directly to a server behined firewall( in DMZ), but I have been resisted. Security guy told me is not correct to assign public ip to a server, it should have private ip for security reasons. Is it true that NAT can provide more security? Hi Tarig, Yes NAT can provide more security, but not in the particular scenario you described. In your scenario, the firewall knows how to map incoming connections for the public address to your server's private address, so you won't see any benefit from NAT versus a merely stateful firewall -- a connection request will either get through the filter or it won't. If it gets through, the firewall knows where to send it. On the other hand, the use of any kind of stateful firewall (most of what we refer to as NAT firewalls keep per-connection state) increases your vulnerability to denial of services attacks: folks DOSing you can target both the server and the firewall's state table. So the use of NAT there is potentially counterproductive. In a client (rather than server) scenario, the picture is different. Depending on the specific NAT technology in use, the firewall may be incapable of selecting a target for unsolicited communications inbound from the public Internet. In fact, it may be theoretically impossible for it to do so. In those scenarios, the presence of NAT in the equation makes a large class of direct attacks on the interior host impractical, requiring the attacker to fall back on other methods like attempting to breach the firewall itself or indirectly polluting the responses to communication initiated by the internal host. No, NAT doesn't provide additional security. The stateful inspection that NAT cannot operate without provides the security. Take away the address mangling and the stateful inspection still provides the same level of security. Owen
Re: Is NAT can provide some kind of protection?
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 On Wed, Jan 12, 2011 at 11:09 AM, Owen DeLong o...@delong.com wrote: No, NAT doesn't provide additional security. The stateful inspection that NAT cannot operate without provides the security. Take away the address mangling and the stateful inspection still provides the same level of security. There is a least one situation where NAT *does* provide a small amount of necessary security. Try this at home, with/without NAT: 1. Buy a new PC with Windows installed 2. Install all security patches needed since the OS was installed Without NAT, you're unpatched PC will get infected in less than 1 minute. Cheers, - - ferg -BEGIN PGP SIGNATURE- Version: PGP Desktop 9.5.3 (Build 5003) wj8DBQFNLf8gq1pz9mNUZTMRAjduAJ4w7az13wwn1zsze0DoLTRvOajxxQCgmWMG ZckeFBpLWyoqG/g9iD2cKIk= =yYof -END PGP SIGNATURE- -- Fergie, a.k.a. Paul Ferguson Engineering Architecture for the Internet fergdawgster(at)gmail.com ferg's tech blog: http://fergdawg.blogspot.com/
Re: IPv6 - real vs theoretical problems
On Jan 12, 2011, at 9:34 AM, Ted Fischer wrote: At 11:59 AM 1/12/2011, Jim postulated wrote: On 01/11/2011 01:31 PM, Owen DeLong wrote: It's not about the number of devices. That's IPv4-think. It's about the number of segments. I see a world where each home-entertainment cluster would be a separate segment (today, few things use IP, but, future HE solutions will include Monitors, Amps, Blu-Ray players, and other Media gateways that ALL have ethernet ports for control and software update). Your future is now, Owen. I have four network devices at my primary television -- the TV itself, TiVo, PS3, and Wii (using the wired adapter). All told, I have seven networked home entertainment devices in my house, with another (Blu-Ray player) likely coming soon. I feel confident in saying that my use case isn't unusual these days. While a lot of the scalability concerns are blown off as not applying to typical consumers, we're quickly getting to the point where your average joe IS somewhat likely to have different classes of devices that might benefit from being on separate subnets. Jima I helped a friend setup his home network recently. He is using an old Linksys Router with no v6 support. I like to be conservative and only allocate what might be needed ... part of my Defense in Depth strategy to provide some layer of security with NAT (yes, I know - my security by obscurity is to use something from 172.16) and a limited amount of addresses to allocate (not to mention WPA2 - he had default no security when I first got there). Used to be a /29 would be sufficient for any home. But, before I knew it, he had a wireless printer, laptop, and 4 iPhones all needing the new wireless passphrase to connect, plus he was anticipating 2 more laptops (one each for his children - to whom 2 of the iPhones belonged), and addresses set aside for guests and the occasional business visitor (he works from home). I left him configured with a /28, and told him to call me if he anticipated more. As a side security note - we lost the laptop on the new secured network before I tracked down that it had automatically logged in to his neighbor's (also unprotected) network on reboot. Ted I'm not sure how you see limiting available addresses as a security feature rather than just a nuisance, but, to each their own. Owen
Re: Is NAT can provide some kind of protection?
On Wed, Mar 21, 2007 at 2:41 AM, Tarig Ahmed tariq198...@hotmail.com wrote: We have wide range of Public IP addresses, I tried to assign public ip directly to a server behined firewall( in DMZ), but I have been resisted. Security guy told me is not correct to assign public ip to a server, it should have private ip for security reasons. Is it true that NAT can provide more security? Thanks, Tarig Yassin Ahmed I assume you are talking about the protection to the current running public facing servers, hence the NAT could not provide more protection to them compares to a proper configed firewall. However, for a small business who does not have its own ASN Provider Independent IP block(s), a NAT (NAT44 and NAT66) could provide lots of protection on IT resources when there is a need to install multiple Internet access lines for providing quickly failover (manual or automatic, doesn't matter) and/or load-sharing capability to end users. -- Michel~
Re: Is NAT can provide some kind of protection?
There is a least one situation where NAT *does* provide a small amount of necessary security. Try this at home, with/without NAT: 1. Buy a new PC with Windows installed 2. Install all security patches needed since the OS was installed Without NAT, you're unpatched PC will get infected in less than 1 minute. Its the firewall included with the NAT which protects against the infection, not the NAT. So you can remove the NAT, leave the firewall, and be just as secure.
Re: Is NAT can provide some kind of protection?
On Jan 12, 2011, at 9:36 AM, Jack Bates wrote: On 1/12/2011 11:21 AM, George Bonser wrote: PAT makes little sense to me for v6, but I suspect you are correct. In addition, we are putting the fire suit on each host in addition to the firewall. Kernel firewall rules on each host for the *nix boxen. As my corp IT guy put it to me, PAT forces a routing disconnect between internal and external. There is no way to reach the hosts without the firewall performing it's NAT function. Given that the internal is exclusively PAT, the DMZ is public with stateful/proxy, this provides protection for the internal network while limiting the dmz exposure. The corp IT guy is delusional. The solution to the routing disconnect is map+encap or tunnels. Many exploits now take advantage of these technologies to use a system compromised through point-click-pwn3d to provide a route into the rest of the network. If you allow outbound access to TCP/80, TCP/443, or TCP/22, then, it is trivial to create an inbound path to your network, NAT or no. The argument everyone makes is that a stateful firewall defaults to deny. However, a single mistake prior to the deny allows traffic in. The only equivalent in a PAT scenario is to screw up port forwarding which would cause a single host to expose a single port unknowingly per mistake (which said port/host combo may not be vulnerable). In a stateful firewall, a screw up could expose all ports on a host or multiple hosts in a single mistake. The argument everyone is making is that a stateful firewall without mangling the headers is just as secure (and just as insecure) as one with PAT. Both can and are trivially compromised. As to the PAT scenario only exposing a single port on a single host, not entirely accurate, either. I have seen errant mappings which exposed much more in a single mapping command on some systems. Then there are the NAT Traversal mechanisms which are necessary to make things function but can also be exploited. The list of problems created by PAT goes on and on. Then there are the firewall software bugs. In PAT, such bugs don't suddenly expose all your hosts behind the firewall for direct communication from the outside world. In v6 stateful firewall, such a bug could allow circumvention of the entire firewall ruleset and the hosts would be directly addressable from the outside. I've seen PAT bugs that exposed multiple hosts. This is false sense of security. PAT offers the smallest of security safeguards. However, many corp IT personnel feel more secure having that small safeguard in place along with the many other safeguards they deploy. In a corporate environment where they often love to break everything and anything, I don't blame them. Paraphrased: A bank vault with a screen door is more secure than a bank vault without a screen door. Pay no attention to the fact that the bank vault was, in this case, built with a skylight. Owen
Re: Cisco Sanitization
On 12/01/11 11:05 AM, Randy Bush wrote: Well, here it is. Perhaps you might consider getting a gmail or other account, and posting on NANOG from there. Either that, or filter Randy out. Personally, I find those silly disclaimers annoying, but am far too lazy to set up a script such as Randy has. disclaimers used to be against nanog list policy. Randy, If you want to cite list policy, let's start by noting that it's a clear violation of the nanog list AUP to setup an autoresponder reply to list email[1], no matter if the autoresponder replies to the list or just to the poster. You must whitelist email from the list before applying an autoresponder. If you don't want to see the disclaimer-laden emails, then you can whitelist, then send posts with disclaimers (along with all other posts you don't care to read) to dev/null. OTOH, there is nothing in the AUP about disclaimers. Disclaimers, top posting, excessive quoting, etc. are discouraged (considered poor netiquette) but not outright forbidden. jc [1] http://www.nanog.org/mailinglist/index.php 8) Autoresponders sending mail either to the list or to the poster are prohibited.
Re: Is NAT can provide some kind of protection?
On Jan 12, 2011, at 11:21 AM, Paul Ferguson wrote: -BEGIN PGP SIGNED MESSAGE- Hash: SHA1 On Wed, Jan 12, 2011 at 11:09 AM, Owen DeLong o...@delong.com wrote: No, NAT doesn't provide additional security. The stateful inspection that NAT cannot operate without provides the security. Take away the address mangling and the stateful inspection still provides the same level of security. There is a least one situation where NAT *does* provide a small amount of necessary security. Try this at home, with/without NAT: 1. Buy a new PC with Windows installed 2. Install all security patches needed since the OS was installed Without NAT, you're unpatched PC will get infected in less than 1 minute. Wrong. Repeat the experiment with stateful firewall with default inbound deny and no NAT. Yep... Same results as NAT. NAT != security. Stateful inspection = some security. Next!! Owen
Re: Is NAT can provide some kind of protection?
Few home users have a stateful firewall configured and AFAIK none of the consumer models come with a good default set of rules much less a drop all unknown. For end users NAT is and will likely to continue to be the most significant and effective front line security they have. Home router manufacturers have very limited budgets for training or support for home end users so the approach is likely to remain the least expensive thing that produces the fewest inbound support calls. If the question is whether NAT was designed to be a security level then I agree your stance and I'd also agree that correctly configured firewalls do a better job at security. Where I disagree is your position that there is no extra security inherent in the default NAT behavior. Until someone makes an effort to create either a DMZ entry or starts doing port forwarding all (AFAIK) of the common routers will drop packets that they don't know where to forward them. Is this a tenuous and accidental security level based on current defaults in cheap gear? Of course, but given how normal users behave until routers can automagically configure firewall settings in a safe (i.e. not UPNP) manner I don't see things changing. On 1/12/2011 2:57 PM, Owen DeLong wrote: On Jan 12, 2011, at 11:21 AM, Paul Ferguson wrote: -BEGIN PGP SIGNED MESSAGE- Hash: SHA1 On Wed, Jan 12, 2011 at 11:09 AM, Owen DeLongo...@delong.com wrote: No, NAT doesn't provide additional security. The stateful inspection that NAT cannot operate without provides the security. Take away the address mangling and the stateful inspection still provides the same level of security. There is a least one situation where NAT *does* provide a small amount of necessary security. Try this at home, with/without NAT: 1. Buy a new PC with Windows installed 2. Install all security patches needed since the OS was installed Without NAT, you're unpatched PC will get infected in less than 1 minute. Wrong. Repeat the experiment with stateful firewall with default inbound deny and no NAT. Yep... Same results as NAT. NAT != security. Stateful inspection = some security. Next!! Owen -- Scott Helms Vice President of Technology ISP Alliance, Inc. DBA ZCorum (678) 507-5000 Looking for hand-selected news, views and tips for independent broadband providers? Follow us on Twitter! http://twitter.com/ZCorum
Re: Cruzio peering
Matthew Kaufman wrote: Have you considered simply asking them? Sadly the person I contacted with regards to some colocation business wasn't able to answer the simplest of question (i.e. from which netblock do they assign IPs). Or at least the question was met with silence (he may still be researching the answer :-). So I felt that asking about peering would be met with even more silence. Someone sent me this link: http://bgp.he.net/AS11994#_peers Thanks, Jeroen -- http://goldmark.org/jeff/stupid-disclaimers/ http://linuxmafia.com/~rick/faq/plural-of-virus.html
Re: Cisco Sanitization
Le mercredi 12 janvier 2011 à 11:41 -0800, JC Dill a écrit : snip/ Randy, If you want to cite list policy, let's start by noting that it's a clear violation of the nanog list AUP to setup an autoresponder reply to list email[1], no matter if the autoresponder replies to the list or just to the poster. You must whitelist email from the list before applying an autoresponder. If you don't want to see the disclaimer-laden emails, then you can whitelist, then send posts with disclaimers (along with all other posts you don't care to read) to dev/null. OTOH, there is nothing in the AUP about disclaimers. Disclaimers, top posting, excessive quoting, etc. are discouraged (considered poor netiquette) but not outright forbidden. Either way, a 15-50 or more lines legal notification style appendix to a mail in an informal operation's forum... ... seems at the very best... to be of... bad taste... (to me). (Who's reading these? :)) Cheers, mh snip/
Re: Is NAT can provide some kind of protection?
On 1/12/2011 1:35 PM, Owen DeLong wrote: The corp IT guy is delusional. The solution to the routing disconnect is map+encap or tunnels. Many exploits now take advantage of these technologies to use a system compromised through point-click-pwn3d to provide a route into the rest of the network. If you allow outbound access to TCP/80, TCP/443, or TCP/22, then, it is trivial to create an inbound path to your network, NAT or no. This presumes the inside network is already compromised. In such a case, a stateful/non-proxy firewall would also be subject to such a thing. This is not what PAT prevents that a stateful firewall doesn't. The argument everyone is making is that a stateful firewall without mangling the headers is just as secure (and just as insecure) as one with PAT. Except that the routing isolation means that it is not just as secure. It has one extra vulnerability over NAT. Both can and are trivially compromised. Agreed that there are still ways around them. Anyone relying on a single mechanism for security will often find their security to be inefficient. As to the PAT scenario only exposing a single port on a single host, not entirely accurate, either. I have seen errant mappings which exposed much more in a single mapping command on some systems. On a standard port redirect, I'd be interested to hear the specifics. However, as my IT guy points out, he doesn't do port or 1-1 redirects through NAT. Then there are the NAT Traversal mechanisms which are necessary to make things function but can also be exploited. Things don't function through his firewall. He likes breakage. The list of problems created by PAT goes on and on. PAT creates a lot of issues. However, for some environments, what it breaks are perfectly acceptable. Utilizing PAT in home routers and facilities that have a more open use of technology, would be crippling the protocol needlessly. I've seen PAT bugs that exposed multiple hosts. This is false sense of security. Specifics. Paraphrased: A bank vault with a screen door is more secure than a bank vault without a screen door. Pay no attention to the fact that the bank vault was, in this case, built with a skylight. If you installed a skylight, that's your own fault. Nowhere have I said, PAT is the ultimate in security and forget everything else. I've said the opposite. PAT has it's uses and does provide certain safeguards. It is one small piece in a huge arsenal of security mechanisms implemented in a network. The entire edge firewall system is only a small piece in network security. If you strictly depend on the edge firewall for security, you may someday learn the error of doing so. Many companies have. Jack
co-location and access to your server
Cruzio in Santa Cruz recently opened a little co-location facility. That makes two of such facilities in Santa Cruz (the other being got.net), which could be a good thing for competition. Their 1U offer comes with limited access to your server, only from 10AM to 6 PM. I find that not acceptable. Why wait until 10 AM when a disk breaks at 8 PM? But maybe I am being too picky. What is considered normal with regards to access to your co-located server(s)? Especially when you're just co-locating one or a few servers. Thanks, Jeroen -- http://goldmark.org/jeff/stupid-disclaimers/ http://linuxmafia.com/~rick/faq/plural-of-virus.html
Re: co-location and access to your server
24x7x365 On Wed, Jan 12, 2011 at 12:24 PM, Jeroen van Aart jer...@mompl.net wrote: Cruzio in Santa Cruz recently opened a little co-location facility. That makes two of such facilities in Santa Cruz (the other being got.net), which could be a good thing for competition. Their 1U offer comes with limited access to your server, only from 10AM to 6 PM. I find that not acceptable. Why wait until 10 AM when a disk breaks at 8 PM? But maybe I am being too picky. What is considered normal with regards to access to your co-located server(s)? Especially when you're just co-locating one or a few servers. Thanks, Jeroen -- http://goldmark.org/jeff/stupid-disclaimers/ http://linuxmafia.com/~rick/faq/plural-of-virus.htmlhttp://linuxmafia.com/%7Erick/faq/plural-of-virus.html
Re: co-location and access to your server
When you are talking single or partial rack colo it is generally done as escorted only, due to security. They can't have anyone coming in and poking around other customers hardware without being watched. We do the same thing but we allow 24x7 escorted access. Half and full racks get 24x7 access also but that is because they are individually locked. -- Matt On Jan 12, 2011, at 3:24 PM, Jeroen van Aart wrote: Cruzio in Santa Cruz recently opened a little co-location facility. That makes two of such facilities in Santa Cruz (the other being got.net), which could be a good thing for competition. Their 1U offer comes with limited access to your server, only from 10AM to 6 PM. I find that not acceptable. Why wait until 10 AM when a disk breaks at 8 PM? But maybe I am being too picky. What is considered normal with regards to access to your co-located server(s)? Especially when you're just co-locating one or a few servers. Thanks, Jeroen -- http://goldmark.org/jeff/stupid-disclaimers/ http://linuxmafia.com/~rick/faq/plural-of-virus.html
Re: co-location and access to your server
The answer, as always, is how much do you want to pay? There are lots of cheap places that make it a hassle for you to get in so you use their remote hands, or just let you in on their terms so they don't have to keep the place open at night. -Jack Carrozzo On Wed, Jan 12, 2011 at 3:24 PM, Jeroen van Aart jer...@mompl.net wrote: Cruzio in Santa Cruz recently opened a little co-location facility. That makes two of such facilities in Santa Cruz (the other being got.net), which could be a good thing for competition. Their 1U offer comes with limited access to your server, only from 10AM to 6 PM. I find that not acceptable. Why wait until 10 AM when a disk breaks at 8 PM? But maybe I am being too picky. What is considered normal with regards to access to your co-located server(s)? Especially when you're just co-locating one or a few servers. Thanks, Jeroen -- http://goldmark.org/jeff/stupid-disclaimers/ http://linuxmafia.com/~rick/faq/plural-of-virus.html
Re: Is NAT can provide some kind of protection?
Once upon a time, Scott Helms khe...@ispalliance.net said: Few home users have a stateful firewall configured Yes, they do. NAT requires a stateful firewall. Why is that so hard to understand? -- Chris Adams cmad...@hiwaay.net Systems and Network Administrator - HiWAAY Internet Services I don't speak for anybody but myself - that's enough trouble.
TeliaSonera US contact?
Does anyone have a (preferably sales) contact with TeliaSonera in the US? I have been trying to get someone to speak to me about a product of theirs (have exchanged email but can't get them on the phone). It might be the time difference with Europe making things difficult so I am wondering if someone might have a contact in North America. Thanks. G
Re: co-location and access to your server
What is considered normal with regards to access to your co-located server(s)? Especially when you're just co-locating one or a few servers. Normally you need an escort so you don't go fiddling with other people's hardware. Our provider has a callout fee if we want to get in at nights or weekends.
Re: Is NAT can provide some kind of protection?
On 1/12/2011 2:13 PM, Scott Helms wrote: Until someone makes an effort to create either a DMZ entry or starts doing port forwarding all (AFAIK) of the common routers will drop packets that they don't know where to forward them. This can be easily implemented in stateful firewalls for home routers. The code is almost identical to NAT, just no address mangling. I suspect that v4 NAT and v6 stateful inspection will actually use the same code in many cases. Not to say NAT doesn't have other uses, but they generally are useful for enterprise networks or sometimes service providers, not home routers. Jack
Re: TeliaSonera US contact?
George, Try Stephen Brown, stephen.br...@teliasonera.com . He is based in Virginia and has always been very good about telephone contact. Jeff On Wed, Jan 12, 2011 at 3:32 PM, George Bonser gbon...@seven.com wrote: Does anyone have a (preferably sales) contact with TeliaSonera in the US? I have been trying to get someone to speak to me about a product of theirs (have exchanged email but can't get them on the phone). It might be the time difference with Europe making things difficult so I am wondering if someone might have a contact in North America. Thanks. G -- Jeffrey Lyon, Leadership Team jeffrey.l...@blacklotus.net | http://www.blacklotus.net Black Lotus Communications - AS32421 First and Leading in DDoS Protection Solutions
RE: co-location and access to your server
If you're co-locating with us, you have access to your equipment 24x7. And we are also staffed 24x7 in the event you can't get to our location for whatever reason...(vacation etc...) Colo's have their own rules I suppose, did you know about this before hosting with them? Date: Wed, 12 Jan 2011 12:24:18 -0800 From: jer...@mompl.net To: nanog@nanog.org Subject: co-location and access to your server Cruzio in Santa Cruz recently opened a little co-location facility. That makes two of such facilities in Santa Cruz (the other being got.net), which could be a good thing for competition. Their 1U offer comes with limited access to your server, only from 10AM to 6 PM. I find that not acceptable. Why wait until 10 AM when a disk breaks at 8 PM? But maybe I am being too picky. What is considered normal with regards to access to your co-located server(s)? Especially when you're just co-locating one or a few servers. Thanks, Jeroen -- http://goldmark.org/jeff/stupid-disclaimers/ http://linuxmafia.com/~rick/faq/plural-of-virus.html
Re: Is NAT can provide some kind of protection?
No it really doesn't. Thank you for leaving the key word when you quoted me (configured). The difference is the _default_ behavior of the two. NAT by _default_ drops packets it doesn't have a mapped PAT translation for. Home firewalls do not _default_ to dropping all packets they don't have a rule to explicitly allow. The behaviors when configured by someone knowledgeable behave the in a similar fashion (allowing packets that are configured to pass and dropping all others) but end users don't do that as a rule. On 1/12/2011 3:31 PM, Chris Adams wrote: Once upon a time, Scott Helmskhe...@ispalliance.net said: Few home users have a stateful firewall configured Yes, they do. NAT requires a stateful firewall. Why is that so hard to understand? -- Scott Helms Vice President of Technology ISP Alliance, Inc. DBA ZCorum (678) 507-5000 Looking for hand-selected news, views and tips for independent broadband providers? Follow us on Twitter! http://twitter.com/ZCorum
Re: co-location and access to your server
On Wed, 12 Jan 2011, Jeroen van Aart wrote: What is considered normal with regards to access to your co-located server(s)? Especially when you're just co-locating one or a few servers. For less than 1 rack, or specialty racks with lockable sections (1/2 or 1/3 or 1/4 racks with their own doors), I'd consider any physical access to simply be a plus. I wouldn't expect any at all. You're not paying for enough space to justify the costs involved in 24x7 independant access, and the risks to other customers gear. When you get a full rack+, or cage+, I'd expect unfettered 24x7 access since your gear should be seperated and secured from other folks gear. Some specialty providers would be exceptions, of course (ie, I used to colo gear inside tv stations, satellite downlink stations, etc). Telecom colo (switch and network gear in a dedicated but shared space for providers providing service) would be an exception, of course. -- david raistrickhttp://www.netmeister.org/news/learn2quote.html dr...@icantclick.org http://www.expita.com/nomime.html
Re: Is NAT can provide some kind of protection?
On Jan 12, 2011, at 12:13 PM, Scott Helms wrote: Few home users have a stateful firewall configured and AFAIK none of the consumer models come with a good default set of rules much less a drop all unknown. For end users NAT is and will likely to continue to be the most significant and effective front line security they have. Home router That's simply not true. Every end user running NAT is running a stateful firewall with a default inbound deny. It then takes the extra step of mangling the packet header. This header mangling step is unnecessary in IPv6 and is not part of the security mechanism. Unfortunately, because these two features have been bundled for so long in IPv4, many people, apparently yourself included, don't see that what most people call a NAT box is actually a stateful-inspection+NAT box doing both steps. manufacturers have very limited budgets for training or support for home end users so the approach is likely to remain the least expensive thing that produces the fewest inbound support calls. If the question is whether NAT was designed to be a security level then I agree your stance and I'd also agree that correctly configured firewalls do a better job at security. Where I disagree is your position that there is no extra security inherent in the default NAT behavior. Until someone makes an effort to create either a DMZ entry or starts doing port forwarding all (AFAIK) of the common routers will drop packets that they don't know where to forward them. And there's no reason they can't function exactly that way in IPv6 without mangling the packet header. Is this a tenuous and accidental security level based on current defaults in cheap gear? Of course, but given how normal users behave until routers can automagically configure firewall settings in a safe (i.e. not UPNP) manner I don't see things changing. Actually, even if it's deliberate, the point here is that it's a three-step process: 1. State table update/match 2. Mangle packet header 3. Forward packet In IPv6, we can discard step 2 without changing the security provided by step 1 and improve the functionality of step 3. Owen On 1/12/2011 2:57 PM, Owen DeLong wrote: On Jan 12, 2011, at 11:21 AM, Paul Ferguson wrote: -BEGIN PGP SIGNED MESSAGE- Hash: SHA1 On Wed, Jan 12, 2011 at 11:09 AM, Owen DeLongo...@delong.com wrote: No, NAT doesn't provide additional security. The stateful inspection that NAT cannot operate without provides the security. Take away the address mangling and the stateful inspection still provides the same level of security. There is a least one situation where NAT *does* provide a small amount of necessary security. Try this at home, with/without NAT: 1. Buy a new PC with Windows installed 2. Install all security patches needed since the OS was installed Without NAT, you're unpatched PC will get infected in less than 1 minute. Wrong. Repeat the experiment with stateful firewall with default inbound deny and no NAT. Yep... Same results as NAT. NAT != security. Stateful inspection = some security. Next!! Owen -- Scott Helms Vice President of Technology ISP Alliance, Inc. DBA ZCorum (678) 507-5000 Looking for hand-selected news, views and tips for independent broadband providers? Follow us on Twitter! http://twitter.com/ZCorum
Re: Is NAT can provide some kind of protection?
On Wed, 12 Jan 2011, Chris Adams wrote: Yes, they do. NAT requires a stateful firewall. Why is that so hard to understand? Um. No. NAT requires stateful inspection (because NAT needs to maintain a state table), but does not require a stateful firewall. You can (and many CPE appliances do/did) have no firewall, or stateless firewall in front of NAT. All NAT does is give you an implied deny-all-inbound rule, but doesn't, in and of itself, prevent someone probing open (configured by you or the vendor) ports that are forwarded or on the device. Or from having unfettered inside access of 1 internal IP if you NAT all external ports to an internal IP. -- david raistrickhttp://www.netmeister.org/news/learn2quote.html dr...@icantclick.org http://www.expita.com/nomime.html
Re: co-location and access to your server
On 1/12/2011 12:28 PM, Matt Kelly wrote: When you are talking single or partial rack colo it is generally done as escorted only, due to security. They can't have anyone coming in and poking around other customers hardware without being watched. We do the same thing but we allow 24x7 escorted access. Half and full racks get 24x7 access also but that is because they are individually locked. -- Matt On Jan 12, 2011, at 3:24 PM, Jeroen van Aart wrote: Cruzio in Santa Cruz recently opened a little co-location facility. That makes two of such facilities in Santa Cruz (the other being got.net), which could be a good thing for competition. Their 1U offer comes with limited access to your server, only from 10AM to 6 PM. I find that not acceptable. Why wait until 10 AM when a disk breaks at 8 PM? But maybe I am being too picky. What is considered normal with regards to access to your co-located server(s)? Especially when you're just co-locating one or a few servers. Thanks, Jeroen -- http://goldmark.org/jeff/stupid-disclaimers/ http://linuxmafia.com/~rick/faq/plural-of-virus.html This is beginning to sound like the blind leading the blind this commentary is too funny. If you outsource your IT facilities to a ISP and you do not plan for redundancy then the failure is YOURS and not the ISP's limited access policy. The ISP's limited access policy has to do with their overhead models and that's all there is to that. Sorry to bring daylight into this but it is what it is... YOU MUST plan for redundancy. Todd Glassey - as a GOT.NET Client - No virus found in this message. Checked by AVG - www.avg.com Version: 10.0.1191 / Virus Database: 1435/3375 - Release Date: 01/12/11
Re: Is NAT can provide some kind of protection?
On 1/12/2011 2:57 PM, Owen DeLong wrote: Try this at home, with/without NAT: 1. Buy a new PC with Windows installed 2. Install all security patches needed since the OS was installed Without NAT, you're unpatched PC will get infected in less than 1 minute. Wrong. Repeat the experiment with stateful firewall with default inbound deny and no NAT. Yep... Same results as NAT. Now let that laptop (or another one on the home subnet) show up with Bridging or Internet Connection Sharing enabled with wired/wireless connections and see what you get. Still maybe OK if it's the host firewall, and it's turned on, and it's not domain-joined with the local subnet allowed, etc., but that was post-SP2 and assumes some malware [or the user] hasn't turned it off. NAT+RFC1918 = no accidental leakage/bridging (yes, they could spoof RFC1918 destinations, assuming they get routed all the way to the endpoint... but that's a bigger if than a public address) Perfect stateful firewall with perfect default inbound deny and no other variables thrown in the mix and yes, but it's breakable in contrast to the NAT+RFC1918 case. There is something to be said for unreachable (i.e., not in your forwarding table) -- else the VPN / VRF / MPLS / etc folks wouldn't have a leg to stand on :-) With that said, this isn't a one-size-fits-all, everybody's perfect solution. We've covered the gamut from home CPE to server farms here, with the original question being about a DMZ case. They are however legitimate security layers applied to certain cloves of this particular bulb of garlic (a more appropriate model than the homogeneous onion) :-) Jeff
Re: Is NAT can provide some kind of protection?
That's simply not true. Every end user running NAT is running a stateful firewall with a default inbound deny. Really? I just tested this with 8 different router models from 5 different manufacturers and in all cases the default behavior was the same. Put a public IP on a PC behind the router, tell the router how to connect (DHCP in this case), and leaving everything else as default meant that all traffic to the public IP was allowed through unless I configured rules. One of the Netgear models (IIRC) did block ICMP but any TCP or UDP traffic was allowed through. Now, this certainly isn't an exhaustive test, but it tested the devices we needed checked. If someone knows of a model that does block incoming (non-established TCP) traffic by default I'd like to know about it. That's especially true of combo DSL modem routers. -- Scott Helms Vice President of Technology ISP Alliance, Inc. DBA ZCorum (678) 507-5000 Looking for hand-selected news, views and tips for independent broadband providers? Follow us on Twitter! http://twitter.com/ZCorum
Re: Is NAT can provide some kind of protection?
On Wed, 12 Jan 2011 15:13:43 EST, Scott Helms said: Few home users have a stateful firewall configured What percent of home users are running a Windows older than XP SP2? pgp0QIpK5GmKt.pgp Description: PGP signature
Re: Is NAT can provide some kind of protection?
On 1/12/2011 3:05 PM, Scott Helms wrote: If someone knows of a model that does block incoming (non-established TCP) traffic by default I'd like to know about it. That's especially true of combo DSL modem routers. I believe Visionnet's v6 dsl modem does, as well as comtrends. Jack
Re: Is NAT can provide some kind of protection?
On Wed, 12 Jan 2011 11:21:24 PST, Paul Ferguson said: Try this at home, with/without NAT: 1. Buy a new PC with Windows installed 2. Install all security patches needed since the OS was installed Without NAT, you're unpatched PC will get infected in less than 1 minute. What release of Windows? pgp0eBWvkExWE.pgp Description: PGP signature
Re: Is NAT can provide some kind of protection?
On Wed, 12 Jan 2011 16:05:42 EST, Scott Helms said: That's simply not true. Every end user running NAT is running a stateful firewall with a default inbound deny. Really? I just tested this with 8 different router models from 5 different manufacturers and in all cases the default behavior was the same. Put a public IP on a PC behind the router At which point you're not running NAT, so it's a different configuration than the one under discussion. pgp0Mhy8ygaKl.pgp Description: PGP signature
Re: World IPv6 Day
On Wed, 12 Jan 2011 11:10:03 -0800 Randy Bush ra...@psg.com wrote: the first global-scale trial of IPv6, the long-anticipated upgrade to the Internet's main communications protocol known as IPv4. this phrasing is both amusing and deeply sad. amusing because many folk have been running ipv6 globaly for over a decade. deeply sad because this is taken to be shiny and new as we approach the end of the iana ipv4 free pool. what have people been smoking? IPv4. Every now and then it is worth remembering that IPv4 was a protocol that was designed for a small experimental network that managed to escape into production. How long it has been usable is actually quite remarkable, and has only been achieved through a series of neat hacks like classes, subnets and CIDR. Regards, Mark.
Re: Is NAT can provide some kind of protection?
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 On Wed, Jan 12, 2011 at 1:18 PM, valdis.kletni...@vt.edu wrote: On Wed, 12 Jan 2011 11:21:24 PST, Paul Ferguson said: Try this at home, with/without NAT: 1. Buy a new PC with Windows installed 2. Install all security patches needed since the OS was installed Without NAT, you're unpatched PC will get infected in less than 1 minute. What release of Windows? Okay, okay -- you got me on that one. :-) It used to be a much bigger problem when XP was shipping on PCs, but of course that has changed. I suppose there's a sliding-window principle (no pun intended) with regards to the number of security vulnerabilities that are remotely exploitable and the amount of time since the OS version was introduced, but you get my point. :-) - - ferg -BEGIN PGP SIGNATURE- Version: PGP Desktop 9.5.3 (Build 5003) wj8DBQFNLhwjq1pz9mNUZTMRAstGAKDhsX9AYZL6sGMIH5WWJM2GpilQNQCgm3TH UQ26ucDTFifTB3eAQEZxj0M= =Lh9p -END PGP SIGNATURE- -- Fergie, a.k.a. Paul Ferguson Engineering Architecture for the Internet fergdawgster(at)gmail.com ferg's tech blog: http://fergdawg.blogspot.com/
Re: Is NAT can provide some kind of protection?
On Jan 12, 2011, at 1:05 PM, Scott Helms wrote: That's simply not true. Every end user running NAT is running a stateful firewall with a default inbound deny. Really? I just tested this with 8 different router models from 5 different manufacturers and in all cases the default behavior was the same. Put a public IP on a PC behind the router, tell the router how to connect (DHCP in this case), and leaving everything else as default meant that all traffic to the public IP was allowed through unless I configured rules. One of the Netgear models (IIRC) did block ICMP but any TCP or UDP traffic was allowed through. Now, this certainly isn't an exhaustive test, but it tested the devices we needed checked. If someone knows of a model that does block incoming (non-established TCP) traffic by default I'd like to know about it. That's especially true of combo DSL modem routers. It may be that the default behavior of the models you tested is to turn off the stateful firewall if there's a public inside address, but, the same code that does the stateful inspection for NAT can do it without NAT if the vendor chooses. I suspect that the vendors chose to automatically disable stateful inspection to avoid tech support calls from ignorant users with public IPs that didn't understand why their packets weren't getting through. Owen
Re: Is NAT can provide some kind of protection?
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 On Wed, Jan 12, 2011 at 1:16 PM, valdis.kletni...@vt.edu wrote: On Wed, 12 Jan 2011 15:13:43 EST, Scott Helms said: Few home users have a stateful firewall configured What percent of home users are running a Windows older than XP SP2? I don't have stats per specific XP SP version, but a sampling of OSs visiting a blog that I admin: 43.40% WinXP 26.33% Win7 13.00% MacOSX 12.60% WinVista 1.60% unknown 1.00% iOS 0.87% Linux 0.87% Android 0.13% Win2003 0.13% Win2000 0.07% SymbianOS Of course, this is just a sampling that may or may not be relevant. - - ferg -BEGIN PGP SIGNATURE- Version: PGP Desktop 9.5.3 (Build 5003) wj8DBQFNLhzuq1pz9mNUZTMRAgN0AJ4hrUq0qSfLLNMWq6RAXleb8bya2ACglxTU tT/sP0oVu89WeWrG6XodcKU= =+pa8 -END PGP SIGNATURE- -- Fergie, a.k.a. Paul Ferguson Engineering Architecture for the Internet fergdawgster(at)gmail.com ferg's tech blog: http://fergdawg.blogspot.com/
Re: co-location and access to your server
todd glassey wrote: On 1/12/2011 12:28 PM, Matt Kelly wrote: When you are talking single or partial rack colo it is generally done policy. The ISP's limited access policy has to do with their overhead models and that's all there is to that. Sorry to bring daylight into this but it is what it is... YOU MUST plan for redundancy. Thanks for all the replies, I understand that allowing access to other people's servers unsupervised could be a bad idea. Problem for my specific situation is that the 10 to 6 access is exactly the time I generally am NOT in town. I guess knowing who entered the building by means of a keycard and having cameras isn't considered enough to deter potential evil doers. I know it's not enough for places like equinix, but that's of a different caliber. Thanks, Jeroen -- http://goldmark.org/jeff/stupid-disclaimers/ http://linuxmafia.com/~rick/faq/plural-of-virus.html
Re: co-location and access to your server
On Wed, 12 Jan 2011, Jeroen van Aart wrote: I guess knowing who entered the building by means of a keycard and having cameras isn't considered enough to deter potential evil doers. I know it's not enough for places like equinix, but that's of a different caliber. Paying for 1u of colo justifys a keycard for you, cameras and keycard hardware for the facility? you're paying what, 50-100$ a month, maybe less? you realize that low prices comes at the cost of reduced services? -- david raistrickhttp://www.netmeister.org/news/learn2quote.html dr...@icantclick.org http://www.expita.com/nomime.html
RE: co-location and access to your server
From: david raistrick Sent: Wednesday, January 12, 2011 1:44 PM To: Jeroen van Aart Cc: NANOG list Subject: Re: co-location and access to your server On Wed, 12 Jan 2011, Jeroen van Aart wrote: I guess knowing who entered the building by means of a keycard and having cameras isn't considered enough to deter potential evil doers. I know it's not enough for places like equinix, but that's of a different caliber. Paying for 1u of colo justifys a keycard for you, cameras and keycard hardware for the facility? you're paying what, 50-100$ a month, maybe less? you realize that low prices comes at the cost of reduced services? I would say even that hosting other people's hardware on a one off basis isn't even really cost effective. Better, in my opinion, for the service provider to simply buy a rack from Rackable or another vendor and rent the servers out to people. At least you are then dealing with a known entity as far as hardware goes. Housing who knows what gives you a potential mix of things like front to back, back to front, and side to side airflow; an assortment of network issues due to an assortment of NICs in the network; people wanting physical access to their servers for things like driver replacement, etc. Even having someone willing to allow individuals to house their own single servers in a rack is amazing. Complaining about the service as far as access just seems like looking the gift horse in the mouth!
Re: co-location and access to your server
On 1/12/2011 12:24, Jeroen van Aart wrote: Cruzio in Santa Cruz recently opened a little co-location facility. That makes two of such facilities in Santa Cruz (the other being got.net), which could be a good thing for competition. Their 1U offer comes with limited access to your server, only from 10AM to 6 PM. I find that not acceptable. Why wait until 10 AM when a disk breaks at 8 PM? But maybe I am being too picky. What is considered normal with regards to access to your co-located server(s)? Especially when you're just co-locating one or a few servers. I treat all my colo customers as 24 hour (escorted) access. ~Seth
Re: co-location and access to your server
On 01/12/2011 03:44 PM, david raistrick wrote: On Wed, 12 Jan 2011, Jeroen van Aart wrote: I guess knowing who entered the building by means of a keycard and having cameras isn't considered enough to deter potential evil doers. I know it's not enough for places like equinix, but that's of a different caliber. Paying for 1u of colo justifys a keycard for you, cameras and keycard hardware for the facility? you're paying what, 50-100$ a month, maybe less? you realize that low prices comes at the cost of reduced services? Having the infrastructure in place to support full cab customers already and 24/7 remote hands, the cost of providing 24/7 access to smaller colo customers is negligible. We could issue a card to every single server one of our colo customers for only the one-time cost of the card. It doesn't make sense for most single-server customers because a tech still has to go into the data center, unlock the cabinet, fetch a crash cart, etc, so he might as well let them in the front door. I guess what you're saying holds true if the facility doesn't already offer /anyone/ this access regardless of how much equipment and space they have. -- Kevin Stange Chief Technology Officer Steadfast Networks http://steadfast.net Phone: 312-602-2689 ext. 203 | Fax: 312-602-2688 | Cell: 312-320-5867 signature.asc Description: OpenPGP digital signature
Re: co-location and access to your server
If it were cheap and I needed a secondary site for backups and DR then I would live with that. Otherwise no. -- Justin Wilson j...@mtin.net Aol Yahoo IM: j2sw http://www.mtin.net/blog xISP News http://www.twitter.com/j2sw Follow me on Twitter Wisp Consulting Tower Climbing Network Support
Re: co-location and access to your server
Kevin Stange wrote: I guess what you're saying holds true if the facility doesn't already offer /anyone/ this access regardless of how much equipment and space they have. They offer 24/7 access to 1/3 racks or more. The price is not that low, $100/month for 1*1U and 1 IP. I'd say that's not a sales bin style rock bottom price where expecting even free coffee is excessive. ;-) There is another small colo in town which to the best of my knowledge does provide 24/7 access with a keycard. Greetings, Jeroen -- http://goldmark.org/jeff/stupid-disclaimers/ http://linuxmafia.com/~rick/faq/plural-of-virus.html
BT Support#
Hi, I am looking for the Enterprise (24x7) technical support contact# for British Telecom (BT), services provided in USA. Thanks Regards, Natarajan Balasubramanian
RE: co-location and access to your server
From: Kevin Stange You're talking about a dedicated server business versus colocation. Colocation can be a better solution if you have special needs for hardware or want to not pay for the extra overhead that needs to be built-in for supporting dedicated hardware (like stocking replacement parts, paying for the server's original purchase cost, extra fees for upgrade hardware, etc). Colo also lets customers move their hardware around if they ever want to change providers, rather than have to do a soft migration and to deliver a prepared server to a facility they can set up at home or in their office beforehand. Depending on your exact needs, some of these things might outweigh the benefits of a dedicated server from the data center operator. Agreed on the above two points. I was thinking that it was great just to find someone these days that would accept a one-off server and that should be enough to be thankful for! The access requirements can be a pain but if you are in a shared cabinet, you have people installing rack mounts, pulling servers in and out around your stuff, etc. I can see where I would probably want the colo provider to have someone supervising what that other customer is doing right next to my server (did he cover my air vents with a bunch of cables?) The degree of clue varies widely between people who might want to collocate a single server and if I am unlucky enough to be hosted directly above/below someone who is in/out of their server every week, I might get a little nervous. Knowing that there is someone with a bit more clue (does that for a living) supervising (or at least witnessing) might ease my anxiety somewhat about what is going on in the cabinet where I am being hosted. As a colo provider, if you set up and enforce rules regarding mounting, air flow, cabling, etc and confirm them when the customer brings them to the facility, this problem does not really exist. To some extent, that is true. I guess it depends on what is going on, too. Does the customer arrive, request their server and the colo provider pulls it for them and deliver it to a work area or does the customer go get the server themselves under supervision of the colo provider? There can be a lot of variables. In our facilities, customers are welcome to come in to work on their hardware at any time 24/7. We do not guarantee or offer that we will have the parts or tools needed to service the equipment and encourage customers to send us those things as needed or take care of the hardware personally in order to deal with any such concerns. This has never been a problem for us. Awesome. It's good to know that there are still operations like that around. That is probably found more often in local providers and not so often in the big operations. The more community oriented providers would be much more accepting of such a situation than a large operation. But having clueful people around 24x7 to assist customers in shared cabinets may not be effective for them if they have just opened up and might not have a lot of customers yet. If they only get one or two customers who come in after hours, I could see where they might figure it isn't cost effective for them to have staff on the swing and graveyard shifts. Larger operations might have an easier time with that, but having someone on call probably isn't that bad if it is infrequently needed.
Routing Suggestions
Hi NANOG list, I have a simple, hypothetical question regarding preferred connectivity methods for you guys that I would like to get the hive mind opinion about. There are two companies, Company A and Company B, that are planning to continuously exchange a large amount of sensitive data and are located in a mutual datacenter. They decide to order a cross connect and peer privately for the obvious reasons. Company A has a small but knowledgable engineering staff and it's network is running BGP as its only routing protocol with multiple transit vendors and a handful of other larger peers. Company B is a smaller shop that is single homed behind one ISP through a default static route, they have hardware that can handle advanced routing protocols but have not had the need to implement them as of yet. There is a single prefix on both sides that will need to be routed to the other party. It is rare that prefixes would need to change or for additional prefixes to be added. From an technical, operational, and security standpoint what would be the preferred way to route traffic between these two networks? Cheers, Lars
Re: Routing Suggestions
On Jan 12, 2011, at 7:13 PM, Lars Carter wrote: Hi NANOG list, I have a simple, hypothetical question regarding preferred connectivity methods for you guys that I would like to get the hive mind opinion about. There are two companies, Company A and Company B ... [ trimmed, but they want to interconnect directly, one does static, the other can do bgp] From an technical, operational, and security standpoint what would be the preferred way to route traffic between these two networks? I suggest using one of the reserved/private BGP asns for this purpose. ASNumber: 64512 - 65535 ASName: IANA-RSVD2 ASHandle: AS64512 RegDate:1995-04-06 Updated:2009-01-14 Comment:Designated for private use [RFC1930] - Jared
Re: Routing Suggestions
On Wed, 12 Jan 2011, Jared Mauch wrote: I suggest using one of the reserved/private BGP asns for this purpose. ASNumber: 64512 - 65535 It sounds to me like Company B isn't doing BGP (probably has no experience with it) and if there's only a single prefix per side of the cross connect, especially if the cross connect is going into routers smart enough to remove a route from the table if the destination interface is down, static would do just fine. -- Jon Lewis, MCP :) | I route Senior Network Engineer | therefore you are Atlantic Net| _ http://www.lewis.org/~jlewis/pgp for PGP public key_
Re: Routing Suggestions
On 1/12/2011 4:13 PM, Lars Carter wrote: Hi NANOG list, I have a simple, hypothetical question regarding preferred connectivity methods for you guys that I would like to get the hive mind opinion about. There are two companies, Company A and Company B, that are planning to continuously exchange a large amount of sensitive data and are located in a mutual datacenter. They decide to order a cross connect and peer privately for the obvious reasons. Company A has a small but knowledgable engineering staff and it's network is running BGP as its only routing protocol with multiple transit vendors and a handful of other larger peers. Company B is a smaller shop that is single homed behind one ISP through a default static route, they have hardware that can handle advanced routing protocols but have not had the need to implement them as of yet. There is a single prefix on both sides that will need to be routed to the other party. It is rare that prefixes would need to change or for additional prefixes to be added. From an technical, operational, and security standpoint what would be the preferred way to route traffic between these two networks? Cheers, Lars Apply the KISS principle. Use a static route
Re: Routing Suggestions
On Wed, Jan 12, 2011, Jon Lewis wrote: On Wed, 12 Jan 2011, Jared Mauch wrote: I suggest using one of the reserved/private BGP asns for this purpose. ASNumber: 64512 - 65535 It sounds to me like Company B isn't doing BGP (probably has no experience with it) and if there's only a single prefix per side of the cross connect, especially if the cross connect is going into routers smart enough to remove a route from the table if the destination interface is down, static would do just fine. Unless you'd like to ensure the sensitive traffic doesn't cross an unsafer default rout path if the XC is down. (Assuming the prefixes are both public IPv4/6 space to begin with.) Adrian -- - Xenion - http://www.xenion.com.au/ - VPS Hosting - Commercial Squid Support - - $24/pm+GST entry-level VPSes w/ capped bandwidth charges available in WA -
Re: co-location and access to your server
George Bonser wrote: Awesome. It's good to know that there are still operations like that around. That is probably found more often in local providers and not so often in the big operations. The more community oriented providers would be much more accepting of such a situation than a large operation. Community oriented provider, that's what I am talking about. I just couldn't find the right term. but having someone on call probably isn't that bad if it is infrequently needed. I'd be willing to pay extra for access after hours, either a recurring fee or on a case by case basis. I am not searching for the cheapest option and demanding that in addition my car be detailed weekly. But just some co-locating space for one or a few servers where I don't have to plan a week ahead or miss half a day of $dayjob in order to work on it (which would cost me more). Greetings, Jeroen -- http://goldmark.org/jeff/stupid-disclaimers/ http://linuxmafia.com/~rick/faq/plural-of-virus.html
Re: Routing Suggestions
Since it sounds like there is no alternate path, it sounds like the most secure, simplest to operate would be static routes. It's not sexy, but no need to toss in a routing protocol if it's such a static setup. --Original Message-- From: Lars Carter To: NANOG@NANOG.org Subject: Routing Suggestions Sent: Jan 12, 2011 7:13 PM Hi NANOG list, I have a simple, hypothetical question regarding preferred connectivity methods for you guys that I would like to get the hive mind opinion about. There are two companies, Company A and Company B, that are planning to continuously exchange a large amount of sensitive data and are located in a mutual datacenter. They decide to order a cross connect and peer privately for the obvious reasons. Company A has a small but knowledgable engineering staff and it's network is running BGP as its only routing protocol with multiple transit vendors and a handful of other larger peers. Company B is a smaller shop that is single homed behind one ISP through a default static route, they have hardware that can handle advanced routing protocols but have not had the need to implement them as of yet. There is a single prefix on both sides that will need to be routed to the other party. It is rare that prefixes would need to change or for additional prefixes to be added. From an technical, operational, and security standpoint what would be the preferred way to route traffic between these two networks? Cheers, Lars Sent from my “contract free” BlackBerry® smartphone on the WIND network.
Re: Routing Suggestions
On Wed, Jan 12, 2011 at 07:13:53PM -0500, Lars Carter wrote: From an technical, operational, and security standpoint what would be the preferred way to route traffic between these two networks? Static routing - at least on the direct link. For extra security, you might want to make sure that the sensitive traffic won't take the internet path, but only the directconnection. Example: 192.168.0.0/24 being the prefix in question. Drop traffic for that /24 via a static Null0 (IOS et al) / discard or reject (JUNOS) route. Then add /25 statics for 192.168.0.0/25 and .128/25 via the direct link. On the BGP speaking network, make sure you don't accept 192.168.0.0/24 or more specifics of that via BGP from untrusted parties. In case the link goes down, the /25s should become inactive, and the /24 Null/discard/reject route prevents leakage of sensitive data in unintended (untrusted) directions (e.g. Internet) via default or covering aggregate routes. Of course all this assumes no dynamic redundancy etc. and some other things not further specified in your scenario. There are many ways to skin a cat. Best regards, Daniel -- CLUE-RIPE -- Jabber: d...@cluenet.de -- d...@ircnet -- PGP: 0xA85C8AA0
Re: Routing Suggestions
On Wed, Jan 12, 2011 at 07:13:53PM -0500, Lars Carter wrote: [snip] There are two companies, Company A and Company B, that are planning to continuously exchange a large amount of sensitive data and are located in a mutual datacenter. They decide to order a cross connect and peer privately for the obvious reasons. Company A has a small but knowledgable engineering staff and it's network is running BGP as its only routing protocol with multiple transit vendors and a handful of other larger peers. Company B is a smaller shop that is single homed behind one ISP through a default static route, they have hardware that can handle advanced routing protocols but have not had the need to implement them as of yet. There is a single prefix on both sides that will need to be routed to the other party. It is rare that prefixes would need to change or for additional prefixes to be added. From an technical, operational, and security standpoint what would be the preferred way to route traffic between these two networks? Use eBGP. Company B runs a mutually-agreed private ASN (at least from company A's unused list). This scales from the initial deployment to multiple cross-connects for failover [or even IPSEC tunnel over public interfaces]. Company B should have Company A provide some clues to their staff if needed (and get more out of the deal). Simple static solutions wind up being entrenched, so move/add/change becomes convoluted. And how many times has one prefix really stayed that way? :-) -- RSUC / GweepNet / Spunk / FnB / Usenix / SAGE
Re: co-location and access to your server
I was thinking that it was great just to find someone these days that would accept a one-off server and that should be enough to be thankful for! Especially true with providers like SoftLayer which can turn up a fully dedicated server to spec at any of several locations within a few hours. No hardware to manage or worrying about getting direct access at all. They even give you the ability to cycle the outlet(s) the server is plugged into if needed. Unless there is some really specialized hardware, location-specific or regulatory need, I couldn't imagine a desire to deal with putting my own single box at a co-lo anymore. Of course, since you're leasing the box you pay a premium over a pure bare-bones co-lo, but it vastly simplifies things. -Justin Scott
Re: Routing Suggestions
On Thu, 13 Jan 2011, Adrian Chadd wrote: On Wed, Jan 12, 2011, Jon Lewis wrote: On Wed, 12 Jan 2011, Jared Mauch wrote: I suggest using one of the reserved/private BGP asns for this purpose. ASNumber: 64512 - 65535 It sounds to me like Company B isn't doing BGP (probably has no experience with it) and if there's only a single prefix per side of the cross connect, especially if the cross connect is going into routers smart enough to remove a route from the table if the destination interface is down, static would do just fine. Unless you'd like to ensure the sensitive traffic doesn't cross an unsafer default rout path if the XC is down. BGP would have that same issue since B is default routing to their provider. [config for B] ip route A's prefix mask gw to A ip route A's prefix mask null0 250 ip route 0.0.0.0 0.0.0.0 B's provider problem solved. If the gw to A is reachable, traffic goes via the cross connect. If the gw is down, traffic goes nowhere. -- Jon Lewis, MCP :) | I route Senior Network Engineer | therefore you are Atlantic Net| _ http://www.lewis.org/~jlewis/pgp for PGP public key_
Re: Routing Suggestions
There are two companies, Company A and Company B, that are planning to continuously exchange a large amount of sensitive data and are located in a mutual datacenter. They decide to order a cross connect and peer privately for the obvious reasons. Second NIC on a secure server at A wired with a crossover cable to a second NIC a secure server at B. Use an RFC1918 /30 that is null routed on both companies routers. KISS. Hand it off to the developers. -- Joe Hamelin, W7COM, Tulalip, WA, 360-474-7474
Re: co-location and access to your server
On 01/12/2011 06:57 PM, Justin Scott wrote: I was thinking that it was great just to find someone these days that would accept a one-off server and that should be enough to be thankful for! Especially true with providers like SoftLayer which can turn up a fully dedicated server to spec at any of several locations within a few hours. No hardware to manage or worrying about getting direct access at all. They even give you the ability to cycle the outlet(s) the server is plugged into if needed. Unless there is some really specialized hardware, location-specific or regulatory need, I couldn't imagine a desire to deal with putting my own single box at a co-lo anymore. Of course, since you're leasing the box you pay a premium over a pure bare-bones co-lo, but it vastly simplifies things. That's true. Most dedicated server providers will get you remote power outlet control and many can get you remote console (IPMI, DRAC) as an included feature, so you can take care of almost all administration on your own, including OS reinstalls and fscks. There's still sometimes an edge in price and control when you use your own hardware and that's definitely worth it for some. -- Kevin Stange Chief Technology Officer Steadfast Networks http://steadfast.net Phone: 312-602-2689 ext. 203 | Fax: 312-602-2688 | Cell: 312-320-5867 signature.asc Description: OpenPGP digital signature
Re: co-location and access to your server
On 1/12/2011 3:24 PM, Jeroen van Aart wrote: What is considered normal with regards to access to your co-located server(s)? Especially when you're just co-locating one or a few servers. Depends on how much you are paying really. If you decide to go with this provider, get dual power supplies, RAID, etc. on the server you will be giving them. You might want instead to look for another provider who offers decent remote hands 24x7 who is in a major market - price should be about the same. --Patrick
Re: Routing Suggestions
On Wed, Jan 12, 2011, Jon Lewis wrote: Unless you'd like to ensure the sensitive traffic doesn't cross an unsafer default rout path if the XC is down. BGP would have that same issue since B is default routing to their provider. [config for B] ip route A's prefix mask gw to A ip route A's prefix mask null0 250 ip route 0.0.0.0 0.0.0.0 B's provider problem solved. If the gw to A is reachable, traffic goes via the cross connect. If the gw is down, traffic goes nowhere. I was just making the observation; the solution is pretty simple. (Yes, I've seen secure network cross-connects get bitten by this. :-) Adrian -- - Xenion - http://www.xenion.com.au/ - VPS Hosting - Commercial Squid Support - - $24/pm+GST entry-level VPSes w/ capped bandwidth charges available in WA -
Re: Routing Suggestions
What Joe Said. Static with 1918 space. If they NEED global space, explain 1918 space will work and tell them to use it. -jim On Wed, Jan 12, 2011 at 9:02 PM, Joe Hamelin j...@nethead.com wrote: There are two companies, Company A and Company B, that are planning to continuously exchange a large amount of sensitive data and are located in a mutual datacenter. They decide to order a cross connect and peer privately for the obvious reasons. Second NIC on a secure server at A wired with a crossover cable to a second NIC a secure server at B. Use an RFC1918 /30 that is null routed on both companies routers. KISS. Hand it off to the developers. -- Joe Hamelin, W7COM, Tulalip, WA, 360-474-7474
Re: Is NAT can provide some kind of protection?
On Wed, Jan 12, 2011 at 12:16 PM, valdis.kletni...@vt.edu wrote: On Wed, 12 Jan 2011 12:04:01 EST, William Herrin said: In a client (rather than server) scenario, the picture is different. Depending on the specific NAT technology in use, the firewall may be incapable of selecting a target for unsolicited communications inbound from the public Internet. In fact, it may be theoretically impossible for it to do so. In those scenarios, the presence of NAT in the equation makes a large class of direct attacks on the interior host impractical, requiring the attacker to fall back on other methods like attempting to breach the firewall itself or indirectly polluting the responses to communication initiated by the internal host. Note that the presence of a firewall with a 'default deny' rule for inbound packets provides the same level of impracticality. Hi Valdis, There's actually a large difference between something that's impossible for a technology to do (even in theory), something that the technology has been programmed not to do and something that a technology is by default configured not to do. The hacker can't make the equipment do something impossible. He can only go around it, try a different attack vector. To push through something the technology has been programmed not to do, he needs to identify a suitable bug: hard but not quite impractical. As for default configurations... human error is a *major* part of the security equation. Identifying and exploiting configuration errors is a hacker's fertile hunting ground. On Wed, Jan 12, 2011 at 2:35 PM, Owen DeLong o...@delong.com wrote: On Jan 12, 2011, at 9:36 AM, Jack Bates wrote: As my corp IT guy put it to me, PAT forces a routing disconnect between internal and external. There is no way to reach the hosts without the firewall performing it's NAT function. Given that the internal is exclusively PAT, the DMZ is public with stateful/proxy, this provides protection for the internal network while limiting the dmz exposure. The corp IT guy is delusional. The solution to the routing disconnect is map+encap or tunnels. Logical fallacy, ad hominem: the sanity of Jack's IT guy is not at issue. Logical fallacy, straw man: that a security technology failed to close attack vectors it was not claimed to have closed makes no statement as to whether the tech blocked the attack vectors it did claim to block. The only technology which stops all possible network attack vectors is the off switch. Logical fallacy, circular reasoning: to bring your magic tunnels into existence, the firewall must have already been breached. Yet you claim the tunnels allow you to breach the firewall, allegedly proving that the PAT routing disconnect is a no-op. It took you only 17 words to get the trifecta. Congratulations, or something. On Wed, Jan 12, 2011 at 2:09 PM, Owen DeLong o...@delong.com wrote: No, NAT doesn't provide additional security. The stateful inspection that NAT cannot operate without provides the security. Take away the address mangling and the stateful inspection still provides the same level of security. When you'd care to offer a refutation of my explanation (above) of exactly how NAT impacts the security process beyond what the stateful inspection does, a refutation that doesn't involve a bunch of bald assertions, hand-waving and logical fallacies, you let me know. Perhaps the security expert you tell me you relied on when formulating your viewpoint could help you out with that? On Wed, Jan 12, 2011 at 2:21 PM, Paul Ferguson fergdawgs...@gmail.com wrote: There is a least one situation where NAT *does* provide a small amount of necessary security. Try this at home, with/without NAT: 1. Buy a new PC with Windows installed 2. Install all security patches needed since the OS was installed Without NAT, you're unpatched PC will get infected in less than 1 minute. Hi Paul, That doesn't really prove your point. Owen is correct that any reasonably configured firewall of any type would tend to prevent such infections. The different firewall types don't begin to exhibit a major difference in security effectiveness until you factor in the impact of human error in specific scenarios. Regards, Bill Herrin -- William D. Herrin her...@dirtside.com b...@herrin.us 3005 Crane Dr. .. Web: http://bill.herrin.us/ Falls Church, VA 22042-3004
Re: Is NAT can provide some kind of protection?
On Jan 12, 2011, at 6:13 PM, William Herrin wrote: On Wed, Jan 12, 2011 at 12:16 PM, valdis.kletni...@vt.edu wrote: On Wed, 12 Jan 2011 12:04:01 EST, William Herrin said: In a client (rather than server) scenario, the picture is different. Depending on the specific NAT technology in use, the firewall may be incapable of selecting a target for unsolicited communications inbound from the public Internet. In fact, it may be theoretically impossible for it to do so. In those scenarios, the presence of NAT in the equation makes a large class of direct attacks on the interior host impractical, requiring the attacker to fall back on other methods like attempting to breach the firewall itself or indirectly polluting the responses to communication initiated by the internal host. Note that the presence of a firewall with a 'default deny' rule for inbound packets provides the same level of impracticality. Hi Valdis, There's actually a large difference between something that's impossible for a technology to do (even in theory), something that the technology has been programmed not to do and something that a technology is by default configured not to do. The hacker can't make the equipment do something impossible. He can only go around it, try a different attack vector. To push through something the technology has been programmed not to do, he needs to identify a suitable bug: hard but not quite impractical. As for default configurations... human error is a *major* part of the security equation. Identifying and exploiting configuration errors is a hacker's fertile hunting ground. NAT boxes without the ability to do port forwarding are few and far between. Human error can poke a hole in a NAT as easily as in a stateful firewall with a default deny. On Wed, Jan 12, 2011 at 2:35 PM, Owen DeLong o...@delong.com wrote: On Jan 12, 2011, at 9:36 AM, Jack Bates wrote: As my corp IT guy put it to me, PAT forces a routing disconnect between internal and external. There is no way to reach the hosts without the firewall performing it's NAT function. Given that the internal is exclusively PAT, the DMZ is public with stateful/proxy, this provides protection for the internal network while limiting the dmz exposure. The corp IT guy is delusional. The solution to the routing disconnect is map+encap or tunnels. Logical fallacy, ad hominem: the sanity of Jack's IT guy is not at issue. The logical fallacy is believing that NAT provides any protection. Logical fallacy, straw man: that a security technology failed to close attack vectors it was not claimed to have closed makes no statement as to whether the tech blocked the attack vectors it did claim to block. The only technology which stops all possible network attack vectors is the off switch. It claimed to provide routing isolation. That alleged isolation is easily circumvented or even configured out of relevance by human error or deliberately. Logical fallacy, circular reasoning: to bring your magic tunnels into existence, the firewall must have already been breached. Yet you claim the tunnels allow you to breach the firewall, allegedly proving that the PAT routing disconnect is a no-op. No, the firewall is presumably configured to intentionally allow access by end users to web sites. Once you allow that, point-click-pwnm3 takes over. It took you only 17 words to get the trifecta. Congratulations, or something. Seriously, Bill... Just because you keep repeating the same sophistry doesn't make it any more believable. On Wed, Jan 12, 2011 at 2:09 PM, Owen DeLong o...@delong.com wrote: No, NAT doesn't provide additional security. The stateful inspection that NAT cannot operate without provides the security. Take away the address mangling and the stateful inspection still provides the same level of security. When you'd care to offer a refutation of my explanation (above) of exactly how NAT impacts the security process beyond what the stateful inspection does, a refutation that doesn't involve a bunch of bald assertions, hand-waving and logical fallacies, you let me know. Perhaps the security expert you tell me you relied on when formulating your viewpoint could help you out with that? Logical fallacy -- Circular argument. Since you call any refutation I offer bald assertions or hand waving when in reality they are behaviors I have observed in the real world, I doubt we'll ever come to agreement on this point. Also, saying things like `the security expert you tell me you relied on' come across as condescending. I have told you that I have discussed the matter with multiple security experts on multiple occasions. The fact that most of them have not given me permission to disclose their contact details to you does not render them any less correct. Finally, I've never told you that I relied on them in forming my viewpoint, only that I have discussed the matter at length and that they share my
