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Date: Fri, 04 May 2007 21:15:33 +0200
From: Andre Oppermann <andre@freebsd.org>
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To: Preethi Natarajan <nataraja@cis.udel.edu>
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Cc: freebsd-net@freebsd.org, "Paul D. Amer" <amer@cis.udel.edu>
Subject: Re: Details on TCP implementation
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Preethi Natarajan wrote:
> Hello,
> 
> I am trying to understand the following details about TCP implementation 
> in FreeBSD (6.1).
> 
> - The sack.enable sysctl turns on SACK options (RFC2018)?

Yes.  It allows SACK to be negotiated during the SYN/SYN-ACK session
setup.

> - Does the implementation leverage SACK information for retransmissions 
> (RFC3517)?

Yes.

> - Is Appropriate Byte Counting (ABC) available (RFC3465) now/in the future?

Not yet but in the future.  It is currently being implemented along
with a 'pluggable' congestion control framework for TCP.

-- 
Andre