This network diagram shows an internal local area network connected to the internet and public switched telephone network through firewalls and routers. The local network contains application servers and devices like phones and faxes. An isolation region separates the internal network from external internet and telephone connections.

1. IE/Navigator DDN/FR
Internet Router
Firewall
Internet Router
PSTN
Switch
Application
Server
Application
Server
Phone
Fax
Internet
Isolation region
Lan