Hi Karsten, Your understanding is completely correct.
Best regards, Xiaohu > -----邮件原件----- > 发件人: Isis-wg [mailto:[email protected]] 代表 Karsten Thomann > 发送时间: 2014年5月9日 16:58 > 收件人: Xuxiaohu; Anton Smirnov > 抄送: [email protected]; George, Wes; [email protected]; joel jaeggli; > OSPF List; [email protected]; [email protected] > 主题: Re: [Isis-wg] [OSPF] 答复: 答复: [sunset4] IPv6 router IDs > > Hi Xiaohu, > > I think I've understand your problem now, but please don't call it a Router > ID, the > router ID must not be an IP address. > To avoid any confusion about it please call it a router ip or router address > within > the TLV. > Please correct me if I'm wrong, but if I understand your drafts right you're > not > requesting a real IPv6 Router ID instead of the (arbitrary) 32bit ID, but a > simple > TLV to carry the routable IPv6 address of the router which advertises the > capability. > > If I understand it right, we should maybe fix the text of the other rfc to > refect > that it is an routable IP address, instead of a (possible) arbitrary but > unique > Router ID. > > Kind regards > Karsten > > Am 09.05.2014 02:53, schrieb Xuxiaohu: > > Hi Anton, > > > > When ISIS capability TLVs are flooded across areas, routers in one area may > need to establish correlations between IP addresses and capabilities of > routers in > another area. For example, assume IS-IS router A in one area has established a > L3VPN session with IS-IS router B in another area. When router A needs to send > L3VPN traffic to router B via a MPLS-SR tunnel, router A wants to know whether > router B (identified by an IP address) has the ELC > (http://tools.ietf.org/html/draft-xu-isis-mpls-elc-00) before inserting an EL > into > the MPLS-SR packet. In such case, it needs to contain at least one routable IP > address in the capability TLV which has been flooded across area boundaries. > In > the IPv4 network, the 4-octect router ID field could contain such routable > IPv4 > address. However, in the IPv6 network, there is no counterpart field to > contain a > routable IPv6 address. > > > > Best regards, > > Xiaohu > > > >> -----邮件原件----- > >> 发件人: Anton Smirnov [mailto:[email protected]] > >> 发送时间: 2014年5月8日 22:49 > >> 收件人: Xuxiaohu > >> 抄送: [email protected]; George, Wes; [email protected]; joel > >> jaeggli; OSPF List; [email protected]; [email protected] > >> 主题: Re: [OSPF] 答复: 答复: [Isis-wg] [sunset4] IPv6 router IDs > >> > >> Hello Xiaohu, > >> this whole thread started from George Wes stating that even in > >> pure > >> IPv4 world Router ID in many protocols is NOT an IPv4 address. For > >> convenience it frequently is but on the binary scale "ID guaranteed > >> to be routable IPv4 address"/"ID is just a number" - the Router ID is NOT > >> an > IPv4 address. > >> > >> So, before you convince people that IPv6 Rtr ID is needed you > >> must start from discussing when and why Router ID is being used as > >> IPv4 address in pure > >> IPv4 world. I believe this in other words is what Acee asking you. > >> > >> Anton > >> > >> > >> On 05/07/2014 03:10 AM, Xuxiaohu wrote: > >>> Hi Acee, > >>> > >>> The motivation for these two drafts > >> (http://tools.ietf.org/html/draft-xu-isis-ipv6-router-id-00 and > >> http://tools.ietf.org/html/draft-xu-ospf-ipv6-router-id-00) is very > >> simple: the > >> IPv6 ISIS|OSPF capability TLV/RI-LSA which are used for advertising > >> router capabilities can be flooded across areas, however, only a > >> 4-octect router ID is carried in them. As a result, it’s hard for > >> routers in one area to establish correlations between IPv6 addresses and > capabilities of routers in another area. > >> For example, assume IS-IS router A in one area has established a > >> L3VPN session with IS-IS router B in another area over their own IPv6 > >> addresses. When router A needs to send L3VPN traffic to router B via > >> a MPLS-SR tunnel, router A wants to know whether router B has the ELC > >> (http://tools.ietf.org/html/draft-xu-isis-mpls-elc-00) before > >> inserting an EL into the MPLS-SR packet . However, the Capability TLV > >> originated by router B doesn’t carried an IPv6 address of its own. As a > >> result, > it ! > >> s hard fo > >> r router A to know the ELC of router B. > >>> Best regards, > >>> Xiaohu > >>> > >>>> -----邮件原件----- > >>>> 发件人: Acee Lindem [mailto:[email protected]] > >>>> 发送时间: 2014年5月6日 21:14 > >>>> 收件人: Xuxiaohu > >>>> 抄送: joel jaeggli; Acee Lindem; George, Wes; [email protected]; OSPF > >>>> List; [email protected]; [email protected]; > >>>> [email protected] > >>>> 主题: Re: [OSPF] 答复: [Isis-wg] [sunset4] IPv6 router IDs > >>>> > >>>> > >>>> On May 5, 2014, at 9:48 PM, Xuxiaohu <[email protected]> wrote: > >>>> > >>>>> > >>>>>> -----邮件原件----- > >>>>>> 发件人: Isis-wg [mailto:[email protected]] 代表 joel jaeggli > >>>>>> 发送时间: 2014年5月5日 23:55 > >>>>>> 收件人: Acee Lindem; Xuxiaohu; George, Wes > >>>>>> 抄送: [email protected]; [email protected]; [email protected]; > >>>>>> [email protected]; [email protected] > >>>>>> 主题: Re: [Isis-wg] [sunset4] IPv6 router IDs > >>>>>> > >>>>>> On 5/5/14, 9:28 AM, Acee Lindem wrote: > >>>>>>> Xiaohu – what are precisely the situations that you think you > >>>>>>> need this > >>>>>>> IPv6 address? > >>>>>>> Acee > >>>>>> if you're using router-id's as equivalency as an ipv4 unicast > >>>>>> addresses. > >>>>>> you're doing so at your peril because there is zero assurance > >>>>>> that those actually map. the first time you have a router id of > >>>>>> 11100000000000000000000000000101 well bummer. > >>>>> The IPv6 router ID sub-TLV of the ISIS router capability TLV must > >>>>> carry a > >>>> "routable" IPv6 address. If the name of the sub-TLV seems > >>>> confusing, it can be changed to IPv6 address sub-TLV. > >>>> > >>>> Independent of what you call it, you didn’t answer my question. > >>>> Other than TE, what the use cases where it is needed? > >>>> > >>>> Acee > >>>> > >>>> > >>>>> Best regards, > >>>>> Xiaohu > >>>>> > >>>>>> I don't find the embedding of semantic meaning in router-ids to > >>>>>> be more compelling then it was in ip addresses. > >>>>>> > >>>>>>> From: Xuxiaohu <[email protected] > >>>> <mailto:[email protected]>> > >>>>>>> Date: Sunday, May 4, 2014 1:29 AM > >>>>>>> To: "George, Wes" <[email protected] > >>>>>>> <mailto:[email protected]>> > >>>>>>> Cc: OSPF - OSPF WG List <[email protected] <mailto:[email protected]>>, > >>>>>>> "[email protected] <mailto:[email protected]>" <[email protected] > >>>>>>> <mailto:[email protected]>>, "[email protected] > >>>>>>> <mailto:[email protected]>" <[email protected] > >>>>>>> <mailto:[email protected]>>, "[email protected] > >>>>>>> <mailto:[email protected]>" <[email protected] > >>>>>>> <mailto:[email protected]>>, "[email protected] > >>>>>> <mailto:[email protected]>" > >>>>>>> <[email protected] > >> <mailto:[email protected]>> > >>>>>>> Subject: Re: [Isis-wg] [sunset4] IPv6 router IDs > >>>>>>> > >>>>>>> Hi Wes, > >>>>>>> > >>>>>>> > >>>>>>> > >>>>>>> Thanks for pointing out these two drafts. > >>>>>>> > >>>>>>> > >>>>>>> > >>>>>>> The motivation for these two drafts > >>>>>>> (http://tools.ietf.org/html/draft-xu-isis-ipv6-router-id-00 and > >>>>>>> http://tools.ietf.org/html/draft-xu-ospf-ipv6-router-id-00) is > very > >>>>>>> simple: the IPv6 ISIS|OSPF capability TLV/RI-LSA which are used > for > >>>>>>> advertising router capabilities can be flooded across areas, > >>>>>>> however, only a 4-octect router ID is carried in them. As a > >>>>>>> result, > >>>>>>> it’s hard for routers in one area to establish correlations > between > >>>>>>> IPv6 addresses and capabilities of routers in another area. For > >>>>>>> example, assume IS-IS router A in one area has established a > L3VPN > >>>>>>> session with IS-IS router B in another area over their own IPv6 > >>>>>>> addresses. When router A needs to send L3VPN traffic to > >>>>>>> router B > >> via > >>>>>>> a MPLS-SR tunnel, router A wants to know whether router B > >>>>>>> has > >> the > >>>>>>> ELC (http://tools.ietf.org/html/draft-xu-isis-mpls-elc-00) before > >>>>>>> > <http://tools.ietf.org/html/draft-xu-isis-mpls-elc-00)%20before> > >>>>>>> inserting an EL into the MPLS-SR packet . However, the > Capability > >>>>>>> TLV originated by router B doesn’t carried an IPv6 address of its > >>>>>>> own. As a result, it’s hard for router A to know the ELC of > router B. > >>>>>>> > >>>>>>> > >>>>>>> > >>>>>>> Best regards, > >>>>>>> > >>>>>>> Xiaohu > >>>>>>> > >>>>>>> > >>>>>>> > >>>>>>> *发件人:*George, Wes [mailto:[email protected]] > >>>>>>> *发送时间:*2014年5月2日1:51 > >>>>>>> *收件人:*Xuxiaohu > >>>>>>> *抄送:*[email protected] <mailto:[email protected]>; > >>>>>>> [email protected] > <mailto:[email protected]>; > >>>>>>> [email protected] > >> <mailto:[email protected]> > >>>>>>> *主题:*Re: [sunset4] IPv6 router IDs > >>>>>>> > >>>>>>> > >>>>>>> > >>>>>>> I got a bounce-back on all 3 draft aliases, trying again with the > >>>>>>> authors’s email addresses directly. > >>>>>>> > >>>>>>> > >>>>>>> > >>>>>>> *From: *<George>, "George, Wes" > <[email protected] > >>>>>>> <mailto:[email protected]>> > >>>>>>> *Date: *Thursday, May 1, 2014 at 1:42 PM > >>>>>>> *To: *"[email protected] > >>>>>>> <mailto:[email protected]>" > >>>>>>> <[email protected] > >>>>>>> <mailto:[email protected]>>, > >>>>>>> "[email protected] > >>>>>>> <mailto:[email protected]>" > >>>>>>> <[email protected] > >>>>>>> <mailto:[email protected]>> > >>>>>>> *Cc: *"[email protected] > >>>>>>> <mailto:[email protected]>" > >>>>>>> <[email protected] > >>>>>>> <mailto:[email protected]>>, > >>>>>>> "[email protected] <mailto:[email protected]>" > <[email protected] > >>>>>>> <mailto:[email protected]>> > >>>>>>> *Subject: *[sunset4] IPv6 router IDs > >>>>>>> > >>>>>>> > >>>>>>> > >>>>>>> I see that you have submitted two drafts for IPv6 router IDs in > ISIS > >>>>>>> and OSPF, noting that the existing router ID is only 4 octets. > >>>>>>> This > >>>>>>> has also come up in IDR for BGP. The authors of that draft are > >>>>>>> copied. I’ll give you a similar set of feedback to what I > >>>>>>> gave them - > >>>>>>> > >>>>>>> > >>>>>>> > >>>>>>> It is important to distinguish between places where a unique > >>>>>>> identifier is needed, and by *convention* an IPv4 address > assigned > >>>>>>> to the device has been used to provide that unique ID, vs. places > >>>>>>> where the actual IP address has some sort of importance to the > >>>>>>> protocol (I.e. That information must be available to take action > on). > >>>>>>> > >>>>>>> In other words, is the protocol requirement that the ID be > unique > >>>>>>> across some domain, but that the actual value does not matter, > or is > >>>>>>> the protocol requirement that the value must correspond to > >> something > >>>>>>> on the router? In many of the former cases, the fact that the > value > >>>>>>> isn’t relevant has been used to make recommendations that > >>>>>>> are > >> easier > >>>>>>> for humans to deal with (I.e. Tying the router ID to an IP > address) > >>>>>>> but that value as a human-readable set of info does not > necessarily > >>>>>>> justify changes to the protocol to support that convention as > we > >>>>>>> move to IPv6. > >>>>>>> > >>>>>>> I would argue that the router ID used in routing protocols must > >>>>>>> merely be unique, but it doesn’t have to be an IP address at all. > >>>>>>> Thus it is not strictly necessary to create a new field to carry > >>>>>>> IPv6 addresses when operating without IPv4 addresses on a > >> network. > >>>>>>> If you believe otherwise, the justification needs to be > documented > >>>>>>> in the draft. > >>>>>>> > >>>>>>> > >>>>>>> > >>>>>>> There are many places in IETF protocols where a 32 bit unique > >>>>>>> identifier is needed, and by convention an IPv4 address has > been > >>>>>>> used. It would be far more useful to write a general draft > >>>>>>> identifying this problem and discussing several solutions, > including > >>>>>>> simply generating unique IDs manually, systematically > generating a > >>>>>>> random ID, etc. the place for such a draft may be in Sunset4, > >>>>>>> either as a part of the existing gap analysis draft or as another > >>>>>>> standalone draft. > >>>>>>> > >>>>>>> > >>>>>>> > >>>>>>> There was rather a long discussion about this on IDR, thread > >>>>>>> here: > >>>>>>> https://mailarchive.ietf.org/arch/search/?qdr=a&email_list=idr&q > >>>>>>> =% > >>>>>>> 22 > >>>>>>> %5 > >>>>>>> Bidr%5D+%5Bv6ops%5D+BGP+Identifier%22&as=1&gbt=1 > >>>>>>> > >>>>>>> > >>>>>>> > >>>>>>> And in the IDR meeting, minutes: > >>>>>>> > >>>>>>> http://www.ietf.org/proceedings/89/minutes/minutes-89-idr > >>>>>>> (see page 11) > >>>>>>> > >>>>>>> > >>>>>>> > >>>>>>> I’d encourage the authors of these drafts to work together on > this. > >>>>>>> > >>>>>>> > >>>>>>> > >>>>>>> Thanks, > >>>>>>> > >>>>>>> > >>>>>>> > >>>>>>> Wes George > >>>>>>> > >>>>>>> > >>>>>>> > >>>>>>> Anything below this line has been added by my company’s > >>>>>>> mail > >> server, > >>>>>>> I have no control over it. > >>>>>>> > >>>>>>> ----------- > >>>>>>> > >>>>>>> > >>>>>>> > >>>>>>> > >>>>>>> ---------------------------------------------------------------- > >>>>>>> -- > >>>>>>> -- > >>>>>>> -- > >>>>>>> -- > >>>>>>> > >>>>>>> This E-mail and any of its attachments may contain Time > >>>>>>> Warner > >> Cable > >>>>>>> proprietary information, which is privileged, confidential, or > >>>>>>> subject to copyright belonging to Time Warner Cable. This > E-mail is > >>>>>>> intended solely for the use of the individual or entity to which > >>>>>>> it > >>>>>>> is addressed. If you are not the intended recipient of this > >>>>>>> E-mail, > >>>>>>> you are hereby notified that any dissemination, distribution, > >>>>>>> copying, or action taken in relation to the contents of and > >>>>>>> attachments to this E-mail is strictly prohibited and may be > >>>>>>> unlawful. If you have received this E-mail in error, please > >>>>>>> notify > >>>>>>> the sender immediately and permanently delete the original > >>>>>>> and > >> any > >>>>>>> copy of this E-mail and any printout. > >>>>>>> > >>>>>>> > >>>>>>> > >>>>>>> _______________________________________________ > >>>>>>> sunset4 mailing list > >>>>>>> [email protected] > >>>>>>> https://www.ietf.org/mailman/listinfo/sunset4 > >>>>>>> > >>>>> _______________________________________________ > >>>>> OSPF mailing list > >>>>> [email protected] > >>>>> https://www.ietf.org/mailman/listinfo/ospf > >>> _______________________________________________ > >>> OSPF mailing list > >>> [email protected] > >>> https://www.ietf.org/mailman/listinfo/ospf > >>> > > _______________________________________________ > > OSPF mailing list > > [email protected] > > https://www.ietf.org/mailman/listinfo/ospf > > _______________________________________________ > Isis-wg mailing list > [email protected] > https://www.ietf.org/mailman/listinfo/isis-wg _______________________________________________ OSPF mailing list [email protected] https://www.ietf.org/mailman/listinfo/ospf
