Subject: Doubt regarding CCP

From: bhanu m <[email-masked]>
Date: Fri, 15 May 1998 17:57:31 -0400 (EDT)

Hi,
    We are developing a product which supports "compression" over "ppp"
link. The algorithms which we are supporting are "stac", "predictor" and
"mppc". 
    Different algo have different method for keeping their Histories in
sync with the peer. Out of these Only Predictor supports clear and
distinct RESET_REQ/RESET_ACK. But we can make Histories in sync if we send
CONF_REQ instead of RESET_REQ when ever decompression failure occurs. i.e.
we can make CCP DOWN and UP. Am I right?
    
    And If I am right then what will you suggest? 
    
    Can you tell that how other Vandors(like CISCO, 3com etc ) are
    handling this?

I am waiting for your response.

Thanks in advance.

Bhanu Marwaha
(Software Engg.)

---

From: James Carlson <[email-masked]>
Date: Fri, 15 May 1998 11:41:54 -0400

> we can make CCP DOWN and UP. Am I right?

Absolutely.  Also, Reset-Request/Reset-Ack is patented by Motorola,
but Configure-Request isn't.  ("I am not a lawyer.")

>     And If I am right then what will you suggest? 

Note that STAC and MPPC both use an in-band technique involving the
header bits to do the Reset-Ack (the "A" bit in the header), but that
they do use Reset-Request.

If you want to support those algorithms and expect good
interoperability, I'm afraid you'll have to use the RFC 1974 and 2118
mechanisms.

>     Can you tell that how other Vandors(like CISCO, 3com etc ) are

Bay uses the RFC-specified mechanisms by default, but will respond
correctly to the Configure-Request mechanism.  I don't know about
others.

-- 
James Carlson, Consulting S/W Engineer  <[email-masked]>
IronBridge Networks / 55 Hayden Avenue  71.246W    Vox:  +1 781 402 8032
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