Why the initial sequence number (ISN) not increase in windows xp sp2?

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I discover the initial sequence number (ISN) algorithm has been modified
so that ISNs in random generated in xp sp2.
 
Why is it important?
How can it be used (or missused)?
Does it open any security issues?

Dusko Savatovic
 
I'm not sure of the point of your post. Random ISNs are good because they
make it far harder to predict sequence numbers and conduct certain kinds
of man-in-the-middle attacks.

Steve Riley
(e-mail address removed)
 
For my question, the key is that the random ISNs disobey the RFC protoals
about TCP/IP for ISNs increment set. They may affect the TCP communication
between the host and the network, result the confusion in communication.

Refrence:
1,Microsoft Windows Server 2003 TCP/IP Implementation Details
http://www.microsoft.com/technet/prodtechnol/windowsserver2003/technologies/networking/tcpip03.mspx
"Windows Server 2003 TCP/IP has also been strengthened against a variety of
attacks that were published over the past couple of years and has been
subject to an internal security review intended to reduce susceptibility to
future attacks. For instance, the initial sequence number (ISN) algorithm has
been modified so that ISNs increase in random increments, using an RC4-based
random number generator initialized with a 2048-bit random key upon system
startup."
2,RFC
 
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