Path: utzoo!utgpu!bnr-vpa!bnr-fos!tpc
From: tpc@bnr-fos.UUCP (Tom Chmara)
Newsgroups: comp.protocols.tcp-ip
Subject: Needed:  timeouts for connections to dead/dying hosts
Keywords: timeout keepalive
Message-ID: <196@bnr-fos.UUCP>
Date: 23 Nov 88 15:06:27 GMT
Reply-To: tpc@bnr-fos.UUCP (Tom Chmara)
Organization: Bell-Northern Research, Ottawa, Canada
Lines: 23

We've been examining the 4.3BSD tcp-ip code from Berkeley, and I'm a bit
confused.  From what I can see, an attempted connection to a dead host
will take TCPTV_KEEP (i.e. 45) seconds.  Timeout of an active connection
on the demise of a remote host will take until all 12 retransmission inter-
vals have expired, i.e. <= (12*TCPTV_MAX = 360s).  The first figure I
can understand...but 6 minutes to timeout on unacknowledged traffic?
Sounds kind of high, even for Internet applications with their long-haul
lines.  Two questions spring to mind:

1) What am I misreading?
2) If this is correct, is it the same for other flavours of TCP-IP?
   If not, has someone got ballpark figures for other implementations?

	Signed,
		Confused
		(a.k.a. ---tpc---)

(thanks for your time, folks...)
-- 
I am sole owner of the above opinions. Licensing inquiries welcome.
------------------------------------------------------------------------
Tom Chmara			UUCP:  ..utgpu!bnr-vpa!bnr-fos!tpc
BNR Ltd.  			BITNET: TPC@BNR.CA