dual-attached

The form of FDDI interface where a device is connected to

both FDDI token-passing rings, so that uninterrupted operation

continues in the event of a failure of either of the rings.

All connections to the main FDDI rings are dual-attached.

Typically, a small number of critical infrastructure devices

such as routers and concentrators are dual-attached,

whereas host computers are normally single-attached or

dual-homed to a router or concentrator.

For example, a ring could be formed between a single router

and two concentrators (all dual-attached) then all other

components that need to be fault-tolerant (typically file

servers) can be dual-homed to both concentrators.

(1994-12-13)