Juniper Networks J-series Services Router J2320 - Manual (Page 40)

J2320 and J2350 Midplane
The J2320 and J2350 midplane is located in the center of the chassis and forms the
rear of the PIM card cage (see Figure 6 on page 16 and Figure 7 on page 17). You
install the PIMs into the midplane from the front of the chassis. Data packets are
transferred across the midplane from the PIM to the Routing Engine, and from the
Routing Engine across the midplane to the destination PIM.
A time-division multiplexing (TDM) bus in J2320 and J2350 routers provides support
for the Avaya VoIP module TGM550. The TGM550 converts the voice path from the
TDM bus to compressed or uncompressed and packetized VoIP on an Ethernet
connection. For more information, see “PIM and VoIP Module Overview” on page 43.
J2320 and J2350 Routing Engine Hardware
The Routing Engine consists of the following components. For more information,
see “Software Overview” on page 39.
■ Processor—Creates the packet forwarding switch fabric for the router and runs
JUNOS software to maintain the router's routing tables and routing protocols.
■ DRAM—Buffers incoming packets and provides storage for the routing and
forwarding tables and for other Routing Engine processes.
To view the amount of DRAM installed on your router, issue the show chassis
routing-engine command.
■ EPROM—Stores the serial number of the Routing Engine.
To view the serial number of the Routing Engine, issue either the show chassis
routing-engine command or the show chassis hardware command.
■ Crypto Accelerator Module—Processor card that enhances performance of
cryptographic algorithms used in IP security (IPSec) services. The cryptographic
algorithms supported include Advanced Encryption Standard (AES), Data
Encryption Standard (DES), triple DES (3DES), Hashed Message Authentication
Code-Message Digest 5 (HMAC-MD5), and HMAC-Secure Hash Algorithm 1
(SHA-1). The Crypto Module is an optional feature of J2320 and J2350 Services
Routers.
To determine whether there is a Crypto Accelerator Module installed on your
router, issue the
show chassis hardware command.
■ Compact flash—Provides primary storage for software images, configuration
files, and microcode. J-series routers have a primary or internal compact flash
located on the system board. For information about replacing the internal
compact flash, see “Replacing Internal Compact Flashes on J2320 and J2350
Routers” on page 178.
J2320 and J2350 Services Routers also provide a slot in the rear of the chassis
into which you can insert an additional external compact flash. For information
about external compact flashes, see “J2320 and J2350 External Compact
Flashes” on page 24.
18 ■ J2320 and J2350 Services Router Hardware Features
J2320, J2350, J4350, and J6350 Services Router Getting Started Guide