I am trying to segment traffic on our remote office network and need assistance. We have a 100MB Ethernet Internet drop in this office, which shares this connection with another pseudo-related entity to our firm. The two "firms" are separated in the building, but have the exact same 3Com Superstack 3226 switch on each end (linked together via a fiber-optic cable run and SPF transceiver in Port 26 on each switch). The 100MB Internet connection is plugged into a single port on our switch (let's call that switch "A") and all of the ports on Switch "A" and the switch in the other firm (lets call that switch "B") are members of the same VLAN currrently.
Recently, we've noticed a severe degradation in the network consistency seen by our firm's staff, but not by the other firm. We don't host servers or other physical devices using Internet Access in our offices (all of our staff have desktop computers with Citrix/RDP access to our main office location)...but the other firm does.
Whether that's a result of the problems we've seen or not, I'd like to segment these two firms such that all of the ports on Switch "B" are on one VLAN, The ports on switch "A" are on their own VLAN...EXCEPT...the port containing the 100MB ethernet connection....which would need to be accessible by both original VLAN's. I know from reading various newsgroup posts, this can only be done a few ways...one of which is with a layer 3 switch...which these two switches are.
I'm pretty sure I know how to set each port to one VLAN or another...but I need to know how to share a port between the two of them? Also, what about the SPF Transceiver port (port 26) linking the two switches by fiber-optic cable....how is this dealt with in the same scenario?
This is something of an urgent issue for us...so anything this community can do to assist, I'd appreciate it.