Page 23 - Intelligent Communication Systems

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COMMUNICATION
FUNDAMENTALS

2.1 CONNECTION-TYPE COMMUNICATION AND
CONNECTIONLESS-TYPE COMMUNICATION

The objective of communication is the interchange of information between a source
and its destination. One way to categorize telecommunication is into connection-
type communication and connectionless-type communication. For connection-type
communication, the source sends a message to its destination and receives acknowl-
edgment from the destination. By comparison, for connectionless-type communi-
cation, a source sends a message to its destination without acknowledgment. The
telephone is an example of connection-type communication. A letter or a postcard
is an example of connectionless-type communication. Connection-type communi-
cation can be characterized by the fact that when the source gets no response from
its destination, the source reissues the message until acknowledgment is returned.
On the other hand, with connectionless-type communication, the source sends a
message to its destination but expects no response from the destination.

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