ADTRAN Express 4110, User Manual

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Chapter 1. Understanding ISDN and the Express 4110/4120
61200176L3-1 Express 4110/4120 User Manual 1-11
Bridging
In Bridge Mode, the Express 4110/4120 can communicate with two
remote networks at a time. The destination is dialed by setting up a Con-
nection List profile and choosing Dial on the Dial menu. See “Configura-
tion/Connection List” on page 3-36 for instructions on setting up a
Connection List profile.
During a two B-channel PPP Multilink call, the Express 4110/4120 auto-
matically drops one B-channel and provides it to the POTS port when a
telephone call is placed or answered. When a POTS telephone call termi-
nates, the Express 4110/4120 redials the second B-channel and supplies
the bandwidth back to the LAN connection. Since other bandwidth man-
agement features are disabled in the factory default configuration, the
dialed links remain active until the Hang-up command is entered from
the Dial menu, terminating the session with the selected remote network.
The Connection List described in the next section may be used to auto-
mate dialing and to store additional information specific to the remote
site being dialed (phone numbers, number of B-channels to dial, authen-
tication information, Caller ID, etc.). In addition, to reduce line charges,
Demand Dialing may be enabled to allow idle links to disconnect when
not being used.
Simple Demand Bridging may be configured by enabling the Idle Time-
Out parameter under the Configuration/ Connection List [1]/Band-
width/On Demand
option on the Connection List. Setting this parame-
ter to a non-zero value allows a bridge connection to disconnect after the
specified number of seconds with no traffic crossing the ISDN link.
Bandwidth can be controlled using the Express 4110/4120’s advanced fil-
tering capability. When new traffic needs to be transmitted, the Express
4110/4120 will run each packet through its Demand filters defined for
each Connection List profile. If a packet can pass through the filter, then
the numbers for that profile are dialed. In addition, when both B-chan-
nels are selected for use, the link may be configured to add/remove the
second B-channel based on the amount of traffic crossing the link. The
bridged connection is terminated when the Hang-up option is selected
from the Dial menu, but will redial if the demand filter condition is met.