User's Manual

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Glossary
T
TCP/IP (Transmission Control Protocol/Internet Protocol)
A suite of communication protocols used to connect hosts on the Internet. Every computer that
wants to communicate with another computer on the Internet must use the TCP/IP protocol to
transmit and route data packets. The format of an IP address is a 32-bit numeric address written as
four octets separated by periods. Each number can be zero to 255. Within an isolated network, you
can assign IP addresses at random as long as each one is unique. However, connecting a private
network to the Internet requires using registered IP addresses to avoid duplication.
The four groups of numbers (octets) are used to identify a particular network and host on that
network. The InterNIC assigns Internet addresses as Class A, Class B, or Class C. Class A
supports 16 million hosts on each of 127 networks. Class B supports 65,000 hosts on each of
16,000 networks. Class C supports 254 hosts on each of 2 million networks. Due to the large
increase in access to the Internet, new classless schemes are gradually replacing the system based
on classes.
U
UDP (User Datagram Protocol)
An Internet Standard transport layer protocol. It is a connectionless protocol that adds a level of
reliability and multiplexing to IP.