Introduction
20
WAN Access Routers Getting Started Guide
2 • Product Overview
Introduction
The WAN Access Router operates as a bridge or a router and has two ports for communication:
•
The Ethernet port—Connects to the LAN side of the connection
•
The Serial port—Connects to local DTE devices (LR121A and LR122A)
•
The T1/E1 port—Connects directly to T1/E1 lines (LR120A)
the router provides all layer 2 and layer 3 protocols required for end-to-end-link communication.
When configuring the WAN Access Router, questions must be answered so the WAN Access Router functions
as desired. For example, when a router or bridge module needs to be activated, some questions would be:
•
Is a default gateway required?
•
Which encapsulation technique is best for this application: Frame Relay, PPP, or another?
These decisions can be made and implemented more easily if the WAN Access Router’s fundamental architecture
is understood. Also, while configuring The WAN Access Router via a browser using the built-in HTTP server is
very intuitive, an understanding of the architecture is essential when using the command-line interface (CLI)
commands.
The fundamental building blocks comprise a router or bridge, interfaces, and transports. the router and bridge
each have interfaces. A transport provides the path between an interface and an external connection. For exam-
ple, the Ethernet transport attaches to an Internet Protocol (IP) interface. A transport consists of layer 2 and
everything below it. Creating a transport and attaching it to a bridge or router’s interface enables data to be
bridged or routed. The supported transports are PPPoE, Frame Relay, PPP, and Ethernet.
Configuring an interface and transport for the router or bridge requires naming the interface and transport before
attaching them. When using the built-in HTTP server web browser, this is done automatically. But when config-
uring The WAN Access Router via CLI commands through the RS-232 control port, it must be done manually.
Summary of Contents for LR120A
Page 1: ...LR120A LR121A LR122A LR125A WAN Access Routers Getting Started Guide...
Page 24: ...19 Chapter 2 Product Overview Chapter contents Introduction 20 Applications overview 21...
Page 115: ...110 Appendix B Cable recommendations Chapter contents Ethernet Cable 111 Adapter 111...
Page 128: ......
