Дорожная карта для Cisco Cisco Tunnel Terminating Gateway (TTG)
ST16 Hardware Platform Overview
▀ Application and Line Cards
▄ Cisco ASR 5000 Series Product Overview
OL-22937-01
Item
Description
5
System Level Status LEDs —Show the status of overall system health and/or maintenance requirements. (See Hardware
Installation Guide for definitions).
Installation Guide for definitions).
6
Alarm Cut-Off (ACO)—Press and release this recessed toggle switch to reset the system alarm speaker and other audible
or visual alarm indicators connected to the CO alarm interface on the SPIO.
or visual alarm indicators connected to the CO alarm interface on the SPIO.
7
Dual PC-Card/PCMCIA Slots—Stores or moves software, diagnostics, and other information.
Figure 20. System Processor Card (SPC)
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Packet Accelerator Card
The PAC provides the packet processing and forwarding within the ST16 hardware platform and used with Switch
Processor Cards (SPCs). Each PAC can support multiple contexts, which allows you to overlap or assign duplicate IP
address ranges in different contexts. PACs are available with either 4 GB or 8GB of memory.
Processor Cards (SPCs). Each PAC can support multiple contexts, which allows you to overlap or assign duplicate IP
address ranges in different contexts. PACs are available with either 4 GB or 8GB of memory.
Important:
All of the PACs in a system must be of the same memory capacity.
Specialized hardware engines are deployed to support parallel distributed processing for compression, classification,
traffic scheduling, forwarding, packet filtering, and statistics.
traffic scheduling, forwarding, packet filtering, and statistics.
The PAC is also available with an optional Encryption Daughter Card (EDC). The EDC permits hardware-based IPSec
encryption for faster processing of encrypted data packets.
encryption for faster processing of encrypted data packets.
The PAC uses control processors to perform packet-processing operations, and a dedicated high-speed network
processing unit (NPU). The NPU does the following:
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
Passes user data frames to and from PAC CPUs
Modifies, adds, or strips datalink/network layer headers
Recalculates checksums
Maintains statistics
Manages both external line card ports and the internal connections to the data and control fabrics
Each PAC has four control processor (CP) subsystems where the bulk of the packet-based user service processing is
done. On 4GB PACs, each CP subsystem has a high-speed CPU and one gigabyte of local memory. On 8GB PACs,
each CP subsystem has a high-speed CPU and two gigabytes of local memory. A fully configured system, utilizing 14
done. On 4GB PACs, each CP subsystem has a high-speed CPU and one gigabyte of local memory. On 8GB PACs,
each CP subsystem has a high-speed CPU and two gigabytes of local memory. A fully configured system, utilizing 14