ISDN and ATM

ISDN and ATM讲稿

Chapter 1. Fundamentals of the Transport Network



1 Transport Network Basics

1. Switched Communications Networks
← Switching---the temporary allocation of network resources.
← The fundamental Switching functions are:
• Reducing the number of lines needed to connect all the users accommodated
in the network; (Figure1.1, Figure 1.2)
• Establishing different connections to allow different Combinations of
users at different times, thus enabling the network resources to be
shared by many users.
← The cost of a telecommunication network depends not only
on the number of connections in the network, but also on
the length of those connections. A simple connection
network model for two ge