Re: draft-ietf-bfd-base-03.txt comments

[Dave Katz <[e-mail]>]

> Would it help the processing cost if done similar to the auth field  
> which is controlled by the "A" flag.?
> Apart from reducing the overhead there is some bandwidth being  
> saved too. For instance, when
> asynchronous mode is active across end systems (and potentially  
> multiple sessions),
> with no echo support, with a 10 msecs tx interval, we could be  
> sending these 4 bytes
> unnecessarily over the period of the session(s) uptime which could  
> run into several days
> between interruptions.

The authentication stuff was made optional partly because of its size  
and complexity (there are environments in which it is unnecessary and  
would stand in the way of efficient implementation in silicon) and  
partly for backward compatibility (the authentication stuff was added  
later in the process.)

The bandwidth savings is essentially invisible (it's totally  
invisible on Ethernet given the minimum packet size requirements.)   
Even at 10 msec intervals at 10Mbps it consumes only an additional . 
03% of the bandwidth, if my math serves.  Just not worth the trouble.

--Dave