Re: setting Initial Window Size of TCP in linux

I am using debian distribution with 2.4 kernel...and I want both to
increase or decrease it...

I suspect you need to crack-open an editor and the compiler.

Just a minute - the receiving end determines its TCP window size (in
both directions).

There are, in broad handwaving terms, three things that limit how much
data is "in flight" at one time on a TCP connection.

The first is what I like to call the "classic" TCP window - it is the
"receive" window advertised by the receiver, and is seen in the TCP
header. Indeed, it is maintained by the receiver.

The second is the congestion window. It is the _sender's_ best guess
as to how much data can be in flight at one time without overloading
some component between the sender and the receiver. It is purely a
figment of the sender's imagination :) (as it were) and does not
appear on the wire in the TCP header.

The third I call the "SO_SNDBUF" window. TCP must retain a reference
to the data it has sent until it receives an ACK from the remote.
Generally, the place where TCP keeps this data is the socket send
buffer, and that is controlled in part by setsockopt() calls setting
SO_SNDBUF - typically bounded by some sort of system configuration
limits. If TCP has no place to keep the reference to the data, it
cannot send it, so it can send no more data at one time than it can
track.

So, the maximum quantity of data outstanding at any one time will be
the minimum of those three things.

rick jones
--
denial, anger, bargaining, depression, acceptance, rebirth...
where do you want to be today?
these opinions are mine, all mine; HP might not want them anyway... :)
feel free to post, OR email to rick.jones2 in hp.com but NOT BOTH...
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