Abstract: A terminal adapter interfaces between a Data Terminating Equipment (DTE) and either a Frame Relay or a Switched Multimegabit Data Service (SMDS) telecommunications network so that the type of network over which the DTE is communicating is transparent to the DTE. The terminal adapter performs mapping from one protocol to another so that a native frame relay DTE can access an SMDS network and so that a native SMDS DTE can access a frame relay network. The address mapping method performed by the terminal adapter uses a parallel table look-up technique which reduces the chance of collision (when two or more addresses hash into the same table entry), eliminates the traditional comparison function to detect a collision, and eliminates the traditional pointer technique when a collision occurs.