Руководство По Устранению Ошибки для Cisco Cisco Packet Data Gateway (PDG)
Cisco ASR 5000 Series System Administration Guide ▄
OL-22970-01
Appendix B
System Software Task and Subsystem Descriptions
System Software Task and Subsystem Descriptions
For redundancy, scalability and robust call processing, the system‘s software is divided into a series of tasks that
perform specific functions. These tasks communicate with each other as needed to share control and data signals. As a
result, system processes can be distributed across multiple tasks thus reducing the overall work-load on any given task
and improving system performance. In addition, this distributed design provides fault containment that greatly
minimizes the impact to the number of processes or sessions due to a failure.
perform specific functions. These tasks communicate with each other as needed to share control and data signals. As a
result, system processes can be distributed across multiple tasks thus reducing the overall work-load on any given task
and improving system performance. In addition, this distributed design provides fault containment that greatly
minimizes the impact to the number of processes or sessions due to a failure.
All tasks run in a Common Firmware Environment (CFE) that resides on specialized Central Processing Units (CPUs)
on each of the application cards. The Packet Services Card (PSC) contains two CPUs (CPU 0 and 1, CPU 0 is the lead
CPU). The CPUs on the PSC are responsible for session processing, and for running the various tasks and processes
required to handle the mobile data call. In addition to the CPUs, PSCs each have a Network Processor Unit (NPU) for IP
forwarding.
on each of the application cards. The Packet Services Card (PSC) contains two CPUs (CPU 0 and 1, CPU 0 is the lead
CPU). The CPUs on the PSC are responsible for session processing, and for running the various tasks and processes
required to handle the mobile data call. In addition to the CPUs, PSCs each have a Network Processor Unit (NPU) for IP
forwarding.
The following sections describe the primary tasks that are implemented by the system: