Overview of the P220 Gigabit Switch Family

Figure 2-1.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 P220G crossbar supports:

❒Nine fabric ports running at full line rate.

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

❒31.68 Gbps total capacity.

❒Under-subscribed switching fabric.

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

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

The P220FE crossbar supports:

❒Five fabric ports running at full line rate.

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

Cajun P550/P220 Switch Operation Guide

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