Reference Guide for the Model RT210/RT211 ISDN Routers
Introduction 1-3
ISDN Support
The Model RT210 and Model RT211 routers are designed to take advantage of ISDN for
transmission of data over digital telephone networks. ISDN allows the telephone networks to carry
data, voice, and video along the same cables. A Basic Rate Interface
(BRI), which is the usual
ISDN implementation, consists of 2 x 64 KBps B channels for data, and a 16 KBps D channel for
control information.
One advantage of using ISDN to connect routers is that the connection is set up only if there is data
to be sent to the remote network. The NETGEAR Model RT210 and Model RT211 ISDN routers
detect that a network exists on a remote unit that can be reached through ISDN. The routers set up
a call, transfer the data, and then hang up automatically when the connection is no longer needed.
Multilink PPP Support
When the single channel ISDN line utilization exceeds a configurable threshold, the NETGEAR
Model RT210 and Model RT211 ISDN routers can automatically establish an additional ISDN call
to provide additional bandwidth. During heavy traffic, the two 64 KBps B channels are combined
using Multilink PPP to provide a fast 128 KBps pipe. When traffic slows down, one of the
B-channels is idled to save toll charges. The router also reverts back to one B-channel for data
when the analog port is used.
TCP/IP Support
The routers support TCP/IP protocol, Routing Information Protocol (RIP), and RIP2 routing
protocols and ensure that ISDN connections are established only when passing data.
For get further information about TCP/IP before installing your router, refer to Appendix B, “TCP/
IP Routing.”
Management Support
The Model RT210 and Model RT211 routers are designed to be installed and made operational
within minutes after connection to the network.
If you are a PC user, the FirstGear software lets you easily configure the unit from the Windows
environment.
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