A uniform method for implementing multiple tunneling protocols in a switch or router is disclosed. The method is based on the realization that although the tunneling protocols are very different, they do share a similar overall structure which can be exploited to create a unified method of dealing with multiple protocols. By using similar data structures to implement multiple protocols, the invention makes data management and programming simple and, therefore, cost effective. According to the invention, all tunneling protocols are abstracted as the mapping of input L2 or L3 streams with output L2 or L3 streams. Mapping is provided by a finite set of tunnel interfaces. The tunnel interfaces map the input streams to output interfaces. As traffic streams flow through these interfaces, they are processed according to defined attributes of these interfaces.