The ABCs of TCP/IP, 2nd Edition

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The ABCs of

TCP/IP

Given an appreciation for the use of active and passive OPEN calls to

establish a TCP connection, one can now explore the manner by which TCP

segments are exchanged. The exchange of segments enables a session to

occur. The initial exchange of datagrams that transport TCP segments is referred

to as a three-way handshake. It is important to note how and why this process

occurs. It has been used in modified form as a mechanism to create a denial-

of-service (DoS) attack, which is discussed in Chapter 5 and 10.

The Three-Way Handshake

To ensure that the sender and receiver are ready to commence the exchange

of data requires that both parties to the exchange be synchronized. Thus,

during the TCP initialization process, the sender ...