I would define anything under the operator’s control are in the trusted zone of 
that operator, including the DC underlay infra as Larry pointed out, if it 
belongs to the same DC operator.
If the end-system and the NVE belong to different operators, then they would 
treat each other as un-trusted. It does not mean they cannot work with each 
other, but some security mitigation, e.g. authentication should be considered.
Luyuan

From: [email protected] [mailto:[email protected]]
Sent: Tuesday, July 10, 2012 11:51 PM
To: Luyuan Fang (lufang)
Cc: [email protected]; Larry Kreeger (kreeger); [email protected]; 
[email protected]; [email protected]
Subject: Re: Re: [nvo3] TES-NVE attach/detach protocol security 
(mobility-issues draft)


Hi, Luyuan

I agree with this text "If the end-system and NVE belongs to the same DC 
operator, then the end-system is in the trusted zone of the operator."
For a another case, for example, end-system and NVE belongs to the DIFFERENT DC 
operator, how can we define the trust zone?

-----------
Yinxing Wei


"Luyuan Fang (lufang)" <[email protected]>
发件人:  [email protected]

2012/07/11 11:27

收件人

"Larry Kreeger (kreeger)" <[email protected]>, "[email protected]" 
<[email protected]>, "[email protected]" <[email protected]>, 
"[email protected]" <[email protected]>

抄送

主题

Re: [nvo3] TES-NVE attach/detach protocol security (mobility-issues draft)






Agree with Larry. It is the end-system talking VDP with the NVE.  If the 
end-system and NVE belongs to the same DC operator, then the end-system is in 
the trusted zone of the operator.

A different point on l3, if it is L3 overlay tunnel starting at the end-system, 
I’d assume no VDP involvement.

Luyuan

From: [email protected] [mailto:[email protected]] On Behalf Of Larry 
Kreeger (kreeger)
Sent: Tuesday, July 10, 2012 11:07 PM
To: [email protected]; [email protected]; [email protected]
Subject: Re: [nvo3] TES-NVE attach/detach protocol security (mobility-issues 
draft)


Trying to clarify the discussion below…using the terminology from 
draft-lasserre-nvo3-framework-03

A TES (tenant end system) is not a trusted entity and would not use VDP to 
communicate to an NVE.  It is an "End System" that would use VDP to communicate 
to an NVE, which would be a trusted device within the data center that is 
administered by the data center operator �C NOT a tenant.

 - Larry

From: David Black <[email protected]<mailto:[email protected]>>
Date: Tuesday, July 10, 2012 9:27 AM
To: "[email protected]<mailto:[email protected]>" 
<[email protected]<mailto:[email protected]>>, 
"[email protected]<mailto:[email protected]>" <[email protected]<mailto:[email protected]>>
Subject: Re: [nvo3] TES-NVE attach/detach protocol security (mobility-issues 
draft)

Linda,

We’re mostly in agreement ...

IEEE802.1 Qbg’s VDP doesn’t do encapsulation, so it is different from NVo3’s 
NVE. VDP allows the hypervisor to notify the network of the virtual network  to 
which the new VMs belong. In that aspect, there is similarity to NVo3’s NVE.

Right - VDP is a protocol that can be used between TES and NVE.  For a 
hypervisor, VDP would only be used on a link to an external NVE (e.g., in the 
ToR switch).  If the NVE is inside the hypervisor there’s no external TES-NVE 
protocol because both the TES and NVE are in the same physical server.

Hypervisor may be trusted, but  I don’t think DC operators can trust VMs.


I agree, and VDP approaches this via use of a link-local destination MAC 
address for all VDP frames sent to the NVE.  If a VM sends a VDP frame, that 
frame is received by a virtual switch in the hypervisor, and so a simple 
solution is for virtual switches to drop and ignore all VDP frames sent by VMs. 
 An SR-IOV NIC would be configured to do likewise for VDP frames sent by VMs.  
In both cases, this enables an external NVE in a ToR switch to rely on the VDP 
frames it receives having been originated by the hypervisor and not the VMs.

Security will be a big concern for any protocols from TES to NVE.

I agree, and any IP based TES-NVE protocol will be unable to rely on link-local 
destination MACs, hence I would expect authentication to be at least a “MUST 
implement” requirement if an IP-based protocol is used.

Thanks,
--David


From: Linda Dunbar [mailto:[email protected]]
Sent: Tuesday, July 10, 2012 11:49 AM
To: Black, David; [email protected]<mailto:[email protected]>
Subject: RE: TES-NVE attach/detach protocol security (mobility-issues draft)


David,

IEEE802.1 Qbg’s VDP doesn’t do encapsulation, so it is different from NVo3’s 
NVE. VDP allows the hypervisor to notify the network of the virtual network  to 
which the new VMs belong. In that aspect, there is similarity to NVo3’s NVE.

Hypervisor may be trusted, but  I don’t think DC operators can trust VMs. When 
VMs are instantiated with applications from random clients, whose applications 
can initiate attack to other clients network. It happened once in Amazon’s EC2.
Security will be a big concern for any protocols from TES to NVE.


Linda

From: [email protected]<mailto:[email protected]> 
[mailto:[email protected]]
Sent: Tuesday, July 10, 2012 8:17 AM
To: Linda Dunbar; [email protected]<mailto:[email protected]>
Subject: TES-NVE attach/detach protocol security (mobility-issues draft)


Hi Linda,

[Linda]  In your IEEE802.1Qbg’s VDP example, the NVE would be the Hypervisor 
which sends Association/De-association messages to the edge bridge. I.e. the 
Hypervisor need to have north bound interface which is aware a VM is add or 
deleted.

I don’t think so.  If the NVE is in the hypervisor, the external Ethernet 
switches (bridges) don’t see the inner MACs after encapsulation, hence VDP to 
the external Ethernet switch (bridge) is not useful because it sets up inner 
MACs that won’t occur in the outer headers beyond the hypervisor’s NVE.  If the 
NVE is in the external Ethernet switch (bridge), VDP is useful because then 
it’s running between the TES and the NVE.


However, it is a security hole to let TES inform NVEs of being added or 
deleted, unless it is in a secure environment, or NVEs (or Hypervisors) can 
validate the information from TES via its management system.

I’m not sure that “secure environment” sets the right expectation.

For an external NVE, it’s necessary to trust the hypervisor to provide info on 
VM attach/detach, so the security concern is that this info come only from the 
hypervisor.



For VDP this starts with use of a link-local destination MAC - if a VM sends to 
this MAC, the virtual switch in the hypervisor is the recipient.  That virtual 
switch doesn’t forward the VDP frames, and probably just drops them. For an 
SR-IOV NIC in the server, the virtual switch in the NIC has to drop VDP frames 
sent by a VM so that VDP frames originate only from the hypervisor.  If an 
IP-based protocol is used for this function, authentication will be needed.  
For an NVE in the hypervisor, the hypervisor configures its virtual switch 
directly and VDP does not run outside the hypervisor.


Thanks,
--David


From: [email protected]<mailto:[email protected]> 
[mailto:[email protected]] On Behalf Of Linda Dunbar
Sent: Monday, July 09, 2012 3:28 PM
To: Guyingjie (Yingjie); [email protected]<mailto:[email protected]>
Subject: Re: [nvo3] Comments on draft-dunbar-nvo3-overlay-mobility-issues


Ying Jie,

Thank you very much for the nice comments. My replies are inserted below:



From: Guyingjie (Yingjie)
Sent: Wednesday, July 04, 2012 8:15 PM
To: [email protected]<mailto:[email protected]>; Linda Dunbar
Subject: Comments on draft-dunbar-nvo3-overlay-mobility-issues


Hi Linda,
I read your draft on NVO3-mobility.
I am okay with most of the content, just some secondary comments on your 
description of mechanism between NVE and TES.
In my mind, external controller assistance is a bit more complicate to 
implement than using a protocol between NVEs and TES.
A premise of my comments is that NVE is on external network devices, such as 
TOR and EOR, and TES are VMs in physical servers.

4.1.1 First paragraph: “NVEs may
   not be aware of VMs being added or deleted unless NVEs have a north
   bound interface to a controller which can communicate with VM/server
   Manager(s).

”
This is not true. In VDP, with an Association/De-association message from 
Hypervisor to edge bridge(i.e. NVE in NVO3, and will use NVE instead of edge 
bridge in below), the bridge can be timely notified about the connect and 
disconnect to the bridge. That means it doesn’t need an northbound API for NVEs 
to be aware of VMs (dis)connection.  And also, VDP protocol can carry a field 
showing “This is a new created VM” or “This is a VM migrated from somewhere 
else”. That is VDP can fulfill the requirement of mobility notification, which 
can be a trigger for NVE to timely updating the states on itself, e.g. 
acquiring VNID associated with the VM moving/adding to the NVE, inner-outer 
address mapping, deleting states associated with the VM moving/deleting from 
this NVE.

[Linda]  In your IEEE802.1Qbg’s VDP example, the NVE would be the Hypervisor 
which sends Association/De-association messages to the edge bridge. I.e. the 
Hypervisor need to have north bound interface which is aware a VM is add or 
deleted.

I think that the sentence should have stated as “NVEs may not be aware of the 
VMs being added or deleted unless NVEs have a north bound interface to a 
controller which can communicate with VM/Server managers, or there is a 
protocol between TES and NVEs as defined by IEEE802.1Qbg.

However, it is a security hole to let TES inform NVEs of being added or 
deleted, unless it is in a secure environment, or NVEs (or Hypervisors) can 
validate the information from TES via its management system.


In the 4th paragraph of 4.1.1, If, for whatever reason, it is necessary to have 
local VID in the
   data frames before encapsulating outer header of EgressNVE-DA/
   IngressNVE-SA /VNID, NVE should get the specific local VID from the
   external Controller for those untagged data frames coming to each
   Virtual Access Point
For some reasons, I don’t think this part is good.
First, there is other way to get the local VID except for external controller. 
In VDP, when NVE receives a (Pre)Association message from TES, it can acquire 
local VID from a Database which is managed by network administrator.
[Linda] Yes, I should have added that NVE can also get local VID from TES as 
IEEE802.1Qbg defined.


Secondly, while defining VDP, we consider of the situation you described, i.e. 
different local VID at different location. So the VDP can support different 
local VID under different NVE, by getting local VID from Database while receive 
the (Pre)Association message. And it can even feedback to the Hypervisor, so 
that the data frames from TES could have the local VID on it, but it’s also 
okay for NVE to add the local VID to data frames.

[Linda] it is all good if TES can have those functions. But in many 
environment, TES don’t. This paragraph is emphasizing on the scenario when TES 
don’t support IEEE802.1Qbg. It is a good idea that you point out the functions 
of IEEE802.1Qbg.


In the 6th paragraph in 4.1.1, The IEEE802.1Qbg's VDP protocol (Virtual Station 
Interface (VSI)
   discovery and configuration protocol) requires hypervisor to send VM
   profile upon a new VM is instantiated. However, not all hypervisors
   support this function.
The following is the VDP TLV definition from Qbg. Each VSI (Virtual Station 
Interface) usually is a VM interface id(could be MAC,IPV4/V6, UUID, etc).
The NVE gets profile from Database by VSI type & instance information. I think 
your profile ID also means the combination of VSI type and instance 
information. So we are talking the same thing.   My point is it’s not profile, 
but the IDs to get profile, that is carried in VDP message. It might be 
confusing to people knowing nothing about VDP. Carrying profile in message is a 
huge overload.




External Controller can be very useful in NVO3, but not best suitable for each 
part of NVO3. I think we should think of other way for different problems.

[Linda] Thanks for sharing this table.

Linda


________________________________

Best Regards
Gu Yingjie
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