E120 And E320 Modules; Srp Module - Juniper E120 - RELEASE 11.1.X HARDWARE GUIDE 3-25-2010 Hardware Manual

Figure 4: E120 Router, Rear View

E120 and E320 Modules

The routers support SRP modules, SFM modules, line modules, and IOAs. You can
use a line module for access or uplink. Access line modules receive traffic from
low-speed circuits, and the system routes the traffic onto higher-speed uplink line
modules and then to the core of the network. Line modules act as frame forwarding
engines for the physical interfaces (the IOAs) via a passive midplane.
Most line modules, IOAs, SFMs, and SRP modules can be installed in either router.
There are a few exceptions, however:
See the E120 and E320 Module Guide for module and chassis compatibility.
The front panel of each module contains a collection of status LEDs (light-emitting
diodes). For information about how to interpret the LEDs, see "Troubleshooting" on
page 79. For complete module specifications, see the E120 and E320 Module Guide.

SRP Module

Switch route processor (SRP) modules perform system management, routing table
calculations and maintenance, forwarding table computations, statistics processing,
configuration storage, and other control plane functions. The SRP module identifies
Similar-capacity modules must be used in the same router. For example, you
cannot install an SRP-100 in a router that contains an SFM-320. You can only
use a SRP–100 module with a SFM-100 module.
Higher-capacity SRP modules can be used in lower-capacity routers, but
lower-capacity SRP modules cannot be used in high-capacity routers. For example,
an SRP-320 can be used in an E120 router, but an SRP-120 cannot be used in
an E320 router.
The SRP-100 module and the SFM-100 module are not supported in the E120
router.
Chapter 1: E120 and E320 Overview
E120 and E320 Modules
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