Improving Network Availability
Circuit Group Considerations
Figure 6. Pool Members of a Circuit Group
The use of pool circuits is ideal in a couple of situations. The first situation is
when the traffic volumes are low and transmissions are infrequent. Transmis-
sions at the end of the business day to update databases are an example. In
this scenario, several (or many) sites are networked together using switched
services. Figure 4 (above) shows a network utilizing pool circuits for this
purpose. The second situation is the use of pool circuits to provide a backup
path for failures of leased lines or packet-switching networks. Figures 7 and
8 illustrate these cases.
3-14
Circuit Group
Terminal
Adapter
Terminal
a
Adapter
Termnial
Adapter
To Switched
Network
To Switched
Network
To Switched
Network
Pool Circuits