E120 And E320 Modules; Srp Module - Juniper E SERIES BROADBAND SERVICES ROUTERS 11.3.X - E120 AND E320 HARDWARE GUIDE REV 9-29-2010 Hardware Manual

E120 and E320 Modules

SRP Module

Copyright © 2010, Juniper Networks, Inc.
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:
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.
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 77. For complete module specifications, see the E120 and E320 Module Guide.
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
which line modules are physically present in the chassis and monitors and controls vital
functions on the line modules.
Each SRP module (Figure 5 on page 8) is a PowerPC-based system with its own memory,
nonvolatile storage (NVS), and power converter. The SRP module works with the SFM
modules and contains a switch fabric slice common to both modules. See "Fabric Slices"
on page 9 for more information.
NOTE: Because of different physical dimensions and switch fabric capabilities,
SRP modules are not interchangeable between all routers. For example, the
SRP–100 used in the E320 router cannot be used in other E Series routers,
and vice versa. See the E120 and E320 Module Guide for SRP module
compatibility.
Chapter 1: E120 and E320 Overview
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