Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.3 4.3bsd-beta 6/6/85; site ucbvax.ARPA Path: utzoo!watmath!clyde!cbosgd!ulysses!ucbvax!tcp-ip From: tcp-ip@ucbvax.ARPA Newsgroups: fa.tcp-ip Subject: Withholding Acks Message-ID: <9526@ucbvax.ARPA> Date: Thu, 1-Aug-85 01:24:51 EDT Article-I.D.: ucbvax.9526 Posted: Thu Aug 1 01:24:51 1985 Date-Received: Fri, 2-Aug-85 01:18:28 EDT Sender: daemon@ucbvax.ARPA Organization: University of California at Berkeley Lines: 24 From: David C. Plummer in disguise Date: Tue 30 Jul 85 10:57:15-EDT From: Lixia Zhang Could someone tell me if there is/are TCP imlementations that withhold acknowledgment packets? And if so, are they the majority? and how do they do it? (I've read rfc813 by Dave Clark on that topic, but I'd like to know whether/how it is implemented.) The Symbolics implementation for 3600s sets a flag in a connection saying "send an ack when you get a chance." Therefore, we do withhold ACKs in a sense. If by withholding acks you are thinking about avoiding silly-window syndrome, that is NOT withholding acks, that is withholding window enlargments. Our implementation does that too. I think just about every implementation does these days. It isn't hard. (It's a bit easier if you deal with limit sequence numbers instead of base+count, since limits stay constant while base increases and count decreases, and just makes my brain hurt making sure they increase/decrease by the same amount...)