Cajun P550 Switch Overview

Crossbar Switch Fabric

The crossbar switch matrix provides low latency, high throughput packet switching using a crossbar architecture (Figure 1-3).

Figure 1-3.Crossbar Architecture

Port 1

22.88 Gb/s

Port 1

1.76 Gb/s

 

 

1.76 Gb/s

Port 2

 

Port 2

 

 

 

 

 

Crossbar

Port 13

 

Port 13

 

 

 

 

 

 

 

 

Crossbars are more scalable than shared memory architectures. Architecturally, you can add more capacity simply by adding more switch elements. By comparison, shared memory switches have an inherent maximum upper boundary in throughput that makes high-density, single-backplane gigabit switches impractical. With a crossbar architecture you increase the number of gigabit ports in your network and the architecture scales to meet your needs.

The crossbar supports:

❒13 fabric ports (two per I/O module slot, plus one for the Supervisor Module).

❒1.76 Gbps (in and out) on each fabric port.

❒22.88 Gbps total capacity, 45.76 Gbps total backplane capacity.

❒Under-subscribed switching fabric in most configurations (two connections per I/O module slot, plus one for the supervisor module).

❒Single copy replication - When possible, input frames destined for output multiple switch ports pass through the crossbar only once and are copied by the crossbar to each destination.

❒Hardware-assisted multicast pruning - The switch only forwards to appropriate destination switch ports.

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Cajun P550/P220 Switch Operation Guide