Specifications

XSR Getting Started Guide 1-1
1
Overview
This chapter introduces key features of the XSR-1850 and briefly describes hardware installation.
System Description
The XSR is a desktop networking device designed for enterprise branch offices that provides IP
routing over FastEthernet LAN and T1/E1, Serial (RS232, X.21, V.35, RS422/530, RS449), Dial
Services via POTS, ISDN (BRI, PRI), or Frame Relay WAN connections. Virtual Private Network
(VPN) and Firewall support is also provided in Site-to-Site or Remote Access applications.
The router can be managed using the Command Line Interface (CLI) and monitored using SNMP
v1, v2c/v3 (with standard MIB-II and proprietary MIB support). The XSR also provides Web
access to display device information.
A typical deployment of the XSR might be in two branch offices connected to a regional office, as
illustrated in Figure 1-1. In this example, one XSR with its associated sub-network has an E1/T1 or
high-speed serial WAN connection as its primary link to the Public Service Telephone Network
(PSTN) with an asynchronous modem connection in a backup capacity.
Figure 1-1 Typical XSR-1850 Topology
PSTN (for PPP)
Network
XSR-1850
Regional site backup:
modem pool
(3rd party RAS)
Primary link:
T1/E1 or serial interface
running PPP
Link backup
with PPP
via external
async modem
Authenticate incoming
PPP connection with
local authentication database
PSTN
IP subnet
XSR-1850 XSR-1850
IP subnet