Subject: Re: Native encapsulation in MP

From: Vernon Schryver <[email-masked]>
Date: Wed, 19 Jul 2000 09:47:21 -0600 (MDT)

> From: Ali Irfan-FIA225 <[email-masked]>

> Situation: MP is used to bundle multiple links.
>
> My questions are: If a user packet is not fragmented, then can it be sent
> native on a link or is the MP encapsulation a must? From my understanding of
> RFC1990, native encapsulation is permitted.

It depends.  Some messages should never be sent with MP encapsulation.

Others such as for bridging, must always be sent with MP encapsulation,
unless you have some other mechanism to prevent reordering, because
they do not tolerate any reordering.

Still others such as IP should be sent with MP encapsulation when there
is any chance of recordering, because TCP/IP lives but does poorly when
reorderd.  When there has been only one link in the bundle for a long time
and a second link is not about to be added or some other conditions, you
can skip MP encapsulation.

>                                                                  If  I  do
> have a MP implementation which sends non-fragmented PPP frames in native
> form, will I have interoperability issues?

It depends on what you mean.

Please consider buying a copy of James Carlson's book 
"PPP Design and Debugging" to answer such questions.

Vernon Schryver    [email-masked]