3Com 10002211 manual Appendix C Vlans on the Corebuilder System

C-2 APPENDIX C: VLANS ON THE COREBUILDER SYSTEM

Port Group VLANs

Port group VLANs group together one or more switch ports. This simple implementation of VLANs requires little configuration. All frames received on a port are grouped together. For example, all frames received on a port that is part of a port group are kept within that port group, regardless of the data contained in the frames. Port groups are useful when traffic patterns are known to be directly associated with particular ports. They can benefit the user by restricting traffic based on a set of simple rules.

MAC Address Group VLANS

VLANs allow a switch to make filtering decisions based on grouping MAC addresses together. These MAC address groups can be configured so that stations in the group can only communicate with each other or with specific network resources. This solution is good for security. It allows the VLAN association to move with the station. However, MAC-address-grouped VLANs may require complex configuration in comparison to other types of VLANs.

Port group and MAC address group VLANs are supported using the packet filtering capabilities in the CoreBuilder system. For information on port group and MAC address group filtering, refer to your CoreBuilder 6000 Operation Guide and CoreBuilder 6000 Administration Console User Guide.

Application-Oriented VLANS

Using the CoreBuilder filtering capability, application-specific traffic such as telnet traffic or FTP traffic can be filtered based on higher-layer information. You create this application-oriented VLAN by configuring packet filters that specify data and offsets of the data within received packets. For example, to use a filter on a particular port for all telnet traffic, create a filter that discards all TCP traffic received on the telnet port.

IP multicast routing and autocast VLANs are additional VLAN features in the CoreBuilder that can be used to group IP multicast traffic for specific applications.