As long as both serial ports are configured for vlan "trunking" you should be fine. A VLAN is layer 2 functionality so IP addressing on the interface is irrelevant unless you want to be able to ping or telnet to the physical ports.
Sounds like you definitely need a connection directly between the 2 sites, either frame relay or leased line. Since you want to bridge between the 2 a leased line might be better because frame relay is best used for bursty traffic. Let me know if y...
Sounds like your link may only be provisioned for 48K, not 64K. My understanding is that the bandwidth field on the "show interface" command is derived from the actual link speed. Check with your service provider to be certain the line has been pro...
