Subject: Re: (IPng 3994) Re: Qry on Traffic Policing (IPv6 header changes)

From: Dimitry Haskin <[email-masked]>
Date: Thu, 12 Jun 1997 11:22:45 -0400

At 09:12 PM 6/11/97 -0700, Steve Deering wrote:
>
>> The question is if it always possible or, more importantly, economical
>> to provide congestion feedback on the timescale and granularity that
>> guaranty that no data discard would be necessary.
>
>No, it's not possible to guarantee that no packets are discarded, when
>using the Internet's "best effort" service.  Adding support for a drop-
>preference bit would not eliminate the possibility of loss of "unmarked"
>packets (i.e., packets without the drop-preference bit set), since there
>could still be bursts of unmarked packets that exceed the bandwidth and
>queueing capacity of a link.  Any application designed to operate over
>best effort service ought to be able to gracefully survive occasional
>packet loss, even of its "most important" packets.
>
>Steve
>
No argument here. But there are many degrees of survival. It can means to
be barely alive with loss of a leg and an arm or to get away with minor
scratches.  I think we talking about potential ways of improving odds for
the latter.

Dimitry