popa3d-users - Re: [PATCH] RFC2449 "CAPA" support

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Date: Thu, 1 Sep 2005 20:33:20 +0400
From: Solar Designer <solar@...nwall.com>
To: popa3d-users@...ts.openwall.com
Subject: Re: [PATCH] RFC2449 "CAPA" support

On Fri, Aug 26, 2005 at 11:09:30PM -0700, N.Cat wrote:
> The problems with with RFC are unfortunate, since it would be nice for popa3d 
> to be able to present the PIPELINING tag to clients. Would this cause the 
> implementation to be inconsistent with RFC 1939 (by implying PIPELINING is 
> optional)?

Yes, but that wouldn't be an RFC violation, so it's fine.  I am more
concerned of this requirement in RFC 2449:

"If either the client or server uses blocking writes, it MUST not exceed
the window size of the underlying transport layer."

As I had explained, this is both meaningless (on server side) and nearly
impossible to guarantee.  By declaring PIPELINING support without
meeting this requirement, popa3d would be violating the RFC.  By not
declaring PIPELINING support, yet supporting CAPA, popa3d would be
telling clients that it does not support pipelining, which is not true.

-- 
Alexander Peslyak <solar at openwall.com>
GPG key ID: B35D3598  fp: 6429 0D7E F130 C13E C929  6447 73C3 A290 B35D 3598
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