On Wed, Nov 19, 2008 at 10:42 AM, Jake Gardner <[EMAIL PROTECTED]> wrote: > All switches of VLan3 configured on the inbound and outbound ports. Only > the inbound port on the first 3812 is UNtagged, the rest are all tagged.
I'm not familiar with the 3Com switches, but it sounds like they work just like our HP's do. If so, the switch portsthe computers are plugged into should be configured as UNtagged for the VLAN you want, *at both ends*. (Unless the computers are running a VLAN-aware network stack, which I'm assuming they are not.) Explanation: Ethernet frames are either "tagged" or "untagged". A tagged frame means the frame has the VLAN tag prefixed to it, which identifies which VLAN the frame is associated with. An untagged frame is just a regular Ethernet frame, with no VLAN information associated with it. If a port is configured as UNtagged for a VLAN, said port will emit frames from said VLAN without a tag. Said frames have nothing that identifies them as coming from a VLAN. This is useful for connecting equipment which is *not* VLAN aware. The equipment will just think it's on a regular LAN, and talk to the switch as such. The switch will accept any untagged frames, and associate them with the UNtagged VLAN. If a port is configured as tagged for a VLAN, that means the port will emit frames with the VLAN tag, and accept frames with VLAN tags, and generally not do anything with VLANs for the computers. The stuff connected to said switch port needs to be VLAN aware. You can have multiple tagged VLANs for the same port, since the frames have the tag that identifies which VLAN they are for. You can only have one untagged VLAN for a port, though. The untagged VLAN means that untagged frames correspond to that untagged VLAN. Hope this helps. -- Ben ~ Finally, powerful endpoint security that ISN'T a resource hog! ~ ~ <http://www.sunbeltsoftware.com/Business/VIPRE-Enterprise/> ~
