Subject: Re: BFD implementation

From: Dave Katz <[email-masked]>
Date: Wed, 2 Feb 2005 22:36:29 -0800

Looks like this never was replied to, sorry...

On Dec 6, 2004, at 7:00 AM, Chris Nogradi wrote:

> Hello, I have some BFD implementation questions:
>
> 1. Section 6.6.2 specifies in the last paragraph that a '... Control 
> packet
> with the Poll (P) bit clear and the Final (F) bit set...' MUST be sent 
> as a
> result of receiving a packet with the poll bit set.  And later, in 
> section
> 6.6.3, the 3rd paragraph states that if the intervals are changed, 
> '... all
> subsequent transmitted Control packets MUST be sent with the Poll (P) 
> bit set
> until a packet is received with the Final (F) bit set.'  It is not 
> clear to
> me how to implement these seemingly contradictory statements.

Good catch.  The statement that all packets have to be sent with Poll 
should not apply to packets being generated in response to a received 
Poll.  This will be fixed...

>
> 2.  While I am not sure that the document specifically states this, it 
> appears
> to me that the poll and final bits should only be set when in the up 
> state?

Yep.  Originally the P/F bits were only used when Demand Mode was 
active, which can only happen in Up state.  However, we leveraged P/F 
for parameter changes.  This should only apply in Up state.  Will be 
fixed...

--Dave