Re: [Idr] BGP: Vendor Specific Capabilities

<> Tue, 22 April 2008 18:48 UTC

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Subject: Re: [Idr] BGP: Vendor Specific Capabilities
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So when you say "ignore", does it mean that peer continues with the connection or drop the connection without sending any notification?

-----Original Message-----
From: ext John G. Scudder []
Sent: Tue 4/22/2008 12:59 PM
To: Mudgal Sundeep (Nokia-S&S/MtView)
Subject: Re: [Idr] BGP:  Vendor Specific Capabilities
It should be ignored.  Per RFC 3392, the unsupported capability  
message is a way to complain if your peer doesn't support a capability  
that you insist on having support for.  An example would be if the  
peer doesn't support MP-BGP and you are trying to establish a v6  
peering.  Here is the pertinent text from RFC 3392:

"If a BGP speaker that supports a certain capability determines that  
its peer doesn't support this capability, the speaker MAY send a  
NOTIFICATION message to the peer, and terminate peering (see Section  
"Extensions to Error Handling" for more details). The Error Subcode in  
the message is set to Unsupported Capability. The message SHOULD  
contain the capability (capabilities) that causes the speaker to send  
the message. The decision to send the message and terminate peering is  
local to the speaker. If terminated, such peering SHOULD NOT be re- 
established automatically."

I apologize for the confusing name of the notification message.   
Probably something like "Required Capability Missing" would have been  
better. :-(

Correct behavior with respect to any unknown capability from your peer  
(whether vendor-specific or otherwise) is generally to ignore it.


On Apr 22, 2008, at 11:35 AM, <> < 
 > wrote:

> Hi,
>         Could you please confirm whether vendor-specific  
> capabilities should be ignored or responded to with the unsupported  
> capability message?
> Thanks,
> Sandeep Mudgal
> _______________________________________________
> Idr mailing list

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