Subject: Re: Flow Control curve ball...

From: "Peter W. Gayek" <[email-masked]>
Date: Thu, 15 Dec 94 20:43:33 EST

I checked with Gene Cox since he originated the piggy-backing idea,
and one key concern was the number of frames that have to flow
to get a circuit up and running, especially for NetBIOS.  I continue
to feel that adding two IFCM frames to the bring-up flow would
cause extra delay that should not be required.  Another approach
would be to back off on the "initial grant owed" policy and
have a new circuit start with an implicit initial 1-window grant.
We could get rid of the piggy-backing that way and perhaps meet
Paul's requirement, although I know Shannon and others were very
much in favor of the "grant owed" policy.

Pandian makes a good point about circuit id's and IFCMs.  I disagree
though about the initial window size needing to acommodate circuit
setup and XIDFRAME messages.  None of these messages are paced, so
they go "for free" and are not counted.  If there is text in draft
15 that suggests otherwise, could you point it out, Pandian, so we
can clarify this?

Peter Gayek

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From: Ravi Periasamy <[email-masked]>
Date: Fri, 16 Dec 94 12:22:12 EST

Peter,

With NetBIOS, the frames that flow between the time we get a Name
Recognized and SABME are all UI Data frames. That are not locally
acked and the end stations retry the frame. So these frames should
also go "for free"!

Also, if I remember it correctly, the latest proposal was to start
the link station NOT with the Name Recognized frame, but with the
SABME that comes in after the NR frame. So we do not require the
piggy-backing for this purpose.

I have not yet really thought through Paul's proposal yet. So no
comments on it yet.

Thanks,
Ravi Periasamy,
[email-masked]

---

From: Gnanaprakasam Pandian <[email-masked]>
Date: Fri, 16 Dec 94 10:11:07 PST

> 15 that suggests otherwise, could you point it out, Pandian, so we

What a bean counter I am!
The text is very clear on this issue by defining "data units".

I stand corrected that the above mentioned frames per spec flow for 
free although I am still wrestling with the 
idea of accomodating buffers for these unaccounted frames.

thanks
	/pandian

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