Windows Networking Tools

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transPort layer ProtoCols

application communicates with TCP is through a series of function

calls. In order to obtain an appreciation for the manner by which TCP

establishes a session we must first examine connection function calls

used by applications, for example, Telnet and FTP.

4.1.2.1 Connection Function Calls Figure 4.4 illustrates the use of

the OPEN connection function calls during the TCP connection

establishment process. is process commences when an application

requires a connection to a remote station. At that time the applica-

tion will request TCP to place an OPEN function call. ere are two

types of OPEN function calls, passive ...