Dynamic reconfiguration of network device's virtual LANs using the root identifiers and root ports determined by a spanning tree procedure

摘要

A system and method of configuring VLANs of a multiple port bridging device by merging potentially conflicting VLANs. One or more VLANs are first defined by the user, and equivalent and subset VLANs are merged. The spanning tree procedure is then performed to determine a root identifier and a root port for each VLAN. The root identifier of each VLAN is compared with the other VLANs, and if equal, the root ports of the two VLANs are compared. If the root identifiers are the same and if the root ports are different for any two VLANs, the two VLANs are merged into a new VLAN. To merge two VLANs, all of the ports of both VLANs are combined to define a new VLAN. Preferably, each VLAN is compared with every other VLAN in this manner. The spanning tree procedure is then executed for the new VLAN, which is then compared to the other VLANs in the same manner. Furthermore, if the root identifiers and the root ports are equal, then it is determined if any shared port of the two VLANs is blocked for one and not the other. If so, the two VLANs are merged into a new VLAN.