Deciding What Type of Tunnel to Configure?

You can configure the ATM logical interface as either an Ethernet ATM bridge tunnel or an FDDI ATM bridge tunnel. To minimize the number of points at which Ethernet-to-FDDI translation is required, you should configure the bridge tunnel according to the following guidelines:

 

If. . .

Then. . .

Source and destination devices on either side of an ATM cloud are both on Ethernet LANs

The tunnel should be an Ethernet ATM bridge tunnel.

Either the source or destination device is on an FDDI ring, and the other device is on an Ethernet LAN

The tunnel should be an FDDI ATM bridge tunnel.

Source and destination devices on either side of an ATM cloud are both on an FDDI ring

The tunnel should be an FDDI ATM bridge tunnel.