> i was wondering, what exactly is the purpose of the VLAN > support on the LAN interface? can someone give me a quick > example of how, why or where this might be used? >
Ideal for firewalling off multiple services which all live at the same trust level. E.g in the bad old days, if one needed to run in external services into an organisation, where one was obliged to keep them logically seperated from each other to prevent your network being used as a transit network. This would have required a rack of firewalls with discrete interfaces, an expensive PITA to maintain and use. This is no joke, I've seen 6 racks of Nokia IP-650s with 20 fast-e interfaces each being deployed just to handle market data. A ridiculous waste of money to provide equivalent port density of single loaded Cat 6509 with far worse packet forwarding performance. OTOH running a gig-e trunk into a switch configured with vacls/pvlan support will provide additional logical interfaces which can then be filtered upon in one place at one time. Greg
