Re: A question about RFC5884

Santosh P K <santosh.pallagatti@gmail.com> Mon, 17 July 2017 08:58 UTC

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From: Santosh P K <santosh.pallagatti@gmail.com>
Date: Mon, 17 Jul 2017 14:28:10 +0530
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Subject: Re: A question about RFC5884
To: Mach Chen <mach.chen@huawei.com>
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I read it as Local discriminator assigned for a BDS session is optional in
echo reply that is being sent in response to LSP ping echo. I don't think
RFC 5884 is not talking about echo reply being optional.

Thanks
Santosh P K

On Sun, Jul 16, 2017 at 7:28 PM, Mach Chen <mach.chen@huawei.com>; wrote:

> Hi BFDers,
>
> We met a multi-vendor interoperate issue recently, it's about whether an
> Echo reply is necessary.
>
> In Section 6 of RFC5884, 2nd paragraph
>
> "... The egress LSR MAY respond with an LSP Ping Echo
>    reply message that carries the local discriminator assigned by it for
>    the BFD session."
>
> >From the above text, my understanding is that an Echo reply is optional,
> the egress LSR can freely to return or not return an Echo reply, and the
> Ingress LSR should not expect there MUST be an Echo reply, but if there is
> one, it should handle it properly.
>
> Is my understanding correct?
>
> Thanks,
> Mach
>
>