Cisco ASR 5000 Series, Installation Manual

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ASR 5000 Hardware Platform Overview
▀ Application Cards
▄ ASR 5000 Installation Guide
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Files copied/removed from CDR module to RAID disk
The hard disk supports SNMP notifications which are described in the SNMP MIB Reference .
Important:
When the hard-disk is filled, dynamically created records files in the folder /hd-raid/record will be
deleted to free up space. Other user-created files on the disk should be cleaned up manually.
Packet Processing Cards: PSC2 and PSC3
The packet processing cards provide packet processing and forwarding capabilities within a system. Each card type
supports multiple contexts, which allows an operator to overlap or assign duplicate IP address ranges in different
contexts.
Caution:
You cannot mix packet processing card types in the same chassis.
Specialized hardware engines support parallel distributed processing for compression, classification, traffic scheduling,
forwarding, packet filtering, and statistics.
The packet processing cards use control processors to perform packet-processing operations, and a dedicated high-speed
network processing unit (NPU). The NPU does the following:

Provides “Fast-path” processing of frames using hardware classifiers to determine each packet’s processing
requirements

Receives and transmits user data frames to and from various physical interfaces

Performs IP forwarding decisions (both unicast and multicast)

Provides per interface packet filtering, flow insertion, deletion, and modification

Manages traffic and traffic engineering
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Modifies, adds, or strips datalink/network layer headers

Recalculates checksums
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Maintains statistics
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Manages both external line card ports and the internal connections to the data and control fabrics
To take advantage of the distributed processing capabilities of the system, you can add packet processing cards to the
chassis without their supporting line cards, if desired. This results in increased packet handling and transaction
processing capabilities. Another advantage is a decrease in CPU utilization when the system performs processor-
intensive tasks such as encryption or data compression.
Packet processing cards can be installed in chassis slots 1 through 7 and 10 through 16. Each card can either Active
(available to the system for session processing) or redundant (a standby component available in the event of a failure).
The front panel of a packet processing card with its major components is shown below.