Re: A question about RFC5884

Mach Chen <mach.chen@huawei.com> Sun, 16 July 2017 20:29 UTC

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From: Mach Chen <mach.chen@huawei.com>
To: Ashesh Mishra <mishra.ashesh@outlook.com>
CC: "rtg-bfd@ietf.org" <rtg-bfd@ietf.org>
Subject: Re: A question about RFC5884
Thread-Topic: A question about RFC5884
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Date: Sun, 16 Jul 2017 20:29:07 +0000
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Hi Ashesh,

Thanks for your prompt response, we're on the same page!

Best regards,
Mach

> -----邮件原件-----
> 发件人: Ashesh Mishra [mailto:mishra.ashesh@outlook.com]
> 发送时间: 2017年7月16日 22:26
> 收件人: Mach Chen
> 抄送: rtg-bfd@ietf.org
> 主题: Re: A question about RFC5884
> 
> That's how I read it ... assuming that proper handling of the LSR echo includes
> gracefully dropping it on rx.
> 
> Ashesh
> 
> On Jul 16, 2017, at 3:58 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