C H A P T E R
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Cisco 10000 Series Router SIP and SPA Hardware Installation Guide
OL-13838-02
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Cisco 10000 Series Router Shared Port Adapters
This chapter describes the shared port adapters (SPAs) that are supported on the Cisco 10000 series
router and contains the following sections:
•
Bandwidth Oversubscription, page 3-13
•
1-Port 10-Gigabit Ethernet SPA Overview, page 3-16
•
2-Port Gigabit Ethernet SPA Overview, page 3-19
•
5-Port Gigabit Ethernet SPA Overview, page 3-23
•
8-Port Gigabit Ethernet SPA Overview, page 3-27
•
2-Port Channelized OC-12/DS0 SPA, page 3-31
Bandwidth Oversubscription
On a Cisco 10000 series router running a Performance Routing Engine 4 (PRE4), each half of the chassis
comprises four slots and is serviced by a single Nickel 10G Application Specific Integrated Circuit
(ASIC) that supports a bandwidth of 11.2 Gbps, as represented in
. The total bandwidth
supported on either half of chassis is limited to 11.2Gbps regardless of number of linecards, SIPs or
SPAs. To maximize throughput, install the SIP or SPA interfaces for ingress and egress, evenly on both
sides of the chassis. This is achieved by using any pair(s) of odd slots on opposite sides of the PREs.
When interfaces are oversubscribed, the line cards on a heavily oversubscribed side receive less overall
bandwidth as compared to the line cards on the undersubscribed side. It is important to balance the
bandwidth between the left and right sides of the chassis when the forwarded throughput is more than
10 Gbps.
