Now that connection-oriented protocols have been discussed, we’ll move on to connectionless
protocols.
Connectionless protocols
differ from connection-oriented protocols because they do
not provide for flow control.
Figure 36.7 shows you how connectionless protocols work. This figure looks somewhat
like Figure 36.3, except that there are no steps that involve a connection setup or
termination. It is also missing the flow control and error control information sent by the
receiving system.
Connectionless protocols do not send data relative to any other data units. The data
included in the PDU must contain enough information for the PDU to get to its destination
and for the receiving system to properly process it. Because there is no established connection,
flow and error control cannot be implemented. Without flow and error control,
the originating system has no way of knowing whether all of the transmitted data was
received by the destination system without errors. Table 36.2 shows examples of connectionless
protocols.