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        RFC 1948:

        Title:      Defending Against Sequence Number Attacks
        Author:     S. Bellovin
        Date:       May 1996
        Mailbox:    smb@research.att.com
        Pages:      6
        Characters: 13,074
        Updates/Obsoletes:  none

        URL:        ftp://ds.internic.net/rfc/rfc1948.txt


IP spoofing attacks based on sequence number spoofing have become a
serious threat on the Internet (CERT Advisory CA-95:01).  While
ubiquitous crypgraphic authentication is the right answer, we propose
a simple modification to TCP implementations that should be a very
substantial block to the current wave of attacks.

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Joyce K. Reynolds
USC/Information Sciences Institute