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)