Path: utzoo!utgpu!jarvis.csri.toronto.edu!rutgers!tut.cis.ohio-state.edu!ucbvax!MATHOM.CISCO.COM!BILLW
From: BILLW@MATHOM.CISCO.COM (William "Chops" Westfield)
Newsgroups: comp.protocols.tcp-ip
Subject: Re: Proper handling of PUSH & small window by sender?
Message-ID: <12566669004.20.BILLW@MATHOM.CISCO.COM>
Date: 16 Feb 90 00:54:33 GMT
References: <589@dino.cs.iastate.edu>
Sender: daemon@ucbvax.BERKELEY.EDU
Organization: The Internet
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PUSH is currently considered rather a bad idea.  It is more of a
user->tcp level thing, as opposed to something that belongs in the
protocol layer.

You should be doing Silly Window Syndrome avoidance regardless of
whether the user sets the PUSH bits, etc.

In theory, once you hand both chunks to the TCP, the boundry between
them dissappears, so if they both fit within a single packet, both
case 2 and case 3, you should probably send a single packet with the
push bit set (offhand, though, it sounds like your application is
not using PUSH correctly - you should read what the hosts requirement
RFC (RFC1122) says about push.)

        +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
        |         chunk1        |        chunk2       |
        +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
 case 1 |<--window--->|
 case 2 |<----------window----------->|
 case 3 |<--------------------window--------------------->|

BillW
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