From owner-freebsd-net  Wed Jan 24 16: 9:46 2001
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Date: Wed, 24 Jan 2001 19:09:23 -0500 (EST)
From: Garrett Wollman <wollman@khavrinen.lcs.mit.edu>
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To: Tatsuhiko Terai <genuine@ma4.justnet.ne.jp>
Cc: freebsd-net@FreeBSD.ORG
Subject: Re: estimation of RTT,RTO from tcpcb parameter
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<<On Thu, 25 Jan 2001 08:36:51 +0900, Tatsuhiko Terai <genuine@ma4.justnet.ne.jp> said:

> Does this program mean that ?
>    RTT = (tp)->t_srtt >> (TCP_RTT_SHIFT - TCP_DELTA_SHIFT) [ms]
>    RTO = tp->t_rxtcur [ms]  

No.  Please take a look at W. Richard Stevens' _TCP/IP Illustrated_
series, particularly volume 2.

Nothing inside the kernel is measured in milliseconds.  TCP parameters
are measured in timer ticks, the length of which depends on which
version of FreeBSD you are running and (potentially) on what hardware
platform.

-GAWollman



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