ADTRAN Express 4120 - Manual (Page 40)

Chapter 1. Understanding ISDN and the Express 4110/4120
1-10 Express 4110/4120 User Manual 61200176L3-1
4. Network Address Translation (NAT): Single networks can connect to
the Internet with this function. The Express 4110/4120 translates out-
going IP packets over the ISDN to the IP router at the Internet Service
Provider. Popular Internet applications are supported.
5. POTS: The POTS interfaces can be used for interfacing to dual tone
multi-frequency (DTMF) analog devices such as telephones, modems,
fax machines, etc.
Demand Routing and Bridging with the Express 4110/4120
The Express 4110/4120 is a dial-up ISDN IP Router and Transparent
Learning Bridge that provides Dial-On-Demand and Dynamic Bandwidth
Management. Its features can be easily configured and used once several
basic concepts are understood.
Factory Default
The Express 4110/4120 comes from the factory configured for MAC
Bridging, IP routing, and IPX routing with no filters or connection infor-
mation defined. An IP address of 10.0.0.1 with a network mask of
255.255.255.0 is preloaded. Dynamic Bandwidth Management features are
disabled. Although dynamic assignment of a B-channel for the analog
(POTS) ports on the Express 4110/4120 is always available, link idle time-
out and adding/removing of B-channels based on traffic is initially dis-
abled.