Subject: PPPmux transmitter stopping criteria in the concatenation process

From: "Daniel Feldman" <[email-masked]>
Date: Tue, 22 May 2001 11:49:04 +0200

Hello friends of PPPmux!
	How can a transmitter know there are no more subframes to
concatenate (stopping criteria iii in the concatenation process)? If the
only way is through a timer, then the paragraph: 
"Implementers may choose additionally to implement using timers. In such
a case a timeout in addition to the conditions stated above is used as a
stopping criteria of the multiplexing process."
	is not needed.
	Thanks a lot,
	Daniel Feldman
IC4IC Ltd.
System Engineer

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From: James Carlson <[email-masked]>
Date: Tue, 22 May 2001 09:02:01 -0400 (EDT)

Daniel Feldman writes:
> concatenate (stopping criteria iii in the concatenation process)?

It's implementation dependent.  One could easily imagine twisted
implementations that either (a) never stop sending packets or (b) have
some sort of "I'm done sending" indication from the transport layer.
These would not need a timer.

> If the

I don't see why that paragraph is unneeded.  Perhaps the "may" should
have been strengthened to "SHOULD," but I don't see how omitting
important implementation information is helpful.

There are two general ways to determine when to stop the multiplexing,
and most implementations probably should use both.  The timer is one
good way to do it.  The other is when the accumulated data would
exceed the peer's MRU.

Still another issue to consider is possible packet priority.  You may
want to terminate multiplexing because a low-priority packet is about
to be appended.

-- 
James Carlson, Internet Engineering       <[email-masked]>
SUN Microsystems / 1 Network Drive         71.234W   Vox +1 781 442 2084
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