Cajun P550 Switch Overview

Figure 1-7.Trunking Translation

Trunking Translation:

F ra m e F o rm at:

•“C lea r” •IEE E

80 2 .1 Q •M u ltila ye r •3C om

Translation Function

Fram e Form at: “Norm al” - E thernet or 802.3 with valid

CRC

Translation Function

F ra m e F o rm at:

•“Clear” •IEE E

802.1Q

•M ultilayer •3C om

Spanning Tree Models

Spanning trees are an IEEE 802.1 standard which provides distributed routing over multiple LANs connected by bridges.

There are three spanning tree models:

❒Single IEEE 802.1D spanning tree

❒Spanning tree per VLAN

❒Optimized “per-VLAN” spanning trees using a scalable, two-layer spanning tree approach

Note: All models interoperate with legacy IEEE 802.1D bridges and switches.

Dual layer spanning trees provide two very important capabilities:

❒Smaller spanning tree domains means much faster convergence during spanning tree reconfiguration.

❒Per-VLAN operation enables you to use more of the available bandwidth when you have redundant links. A particular link can be blocked on one VLAN, but still forward packets on another.

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Cajun P550/P220 Switch Operation Guide