The TCP agent does not generate any application data on its own;
instead, the simulation user can connect any traffic generation
module to the TCP agent to generate data.
Two applications are commonly used for TCP: FTP and Telnet.
FTP represents a bulk data transfer of large size, and telnet chooses
its transfer sizes randomly from tcplib (see the file
tcplib-telnet.cc.
Details on configuring these application source objects are in
Section 40.4.
Tom Henderson
2011-11-05