An ISDN interface is provided on a card, which is adapted for mounting in a terminal computer and which is operable to exchange data with a terminal computer and an ISDN. The ISDN interface card includes a protocol processor that is programmable to process data encoded in accordance with ...http://www.google.es/patents/US5832240?utm_source=gb-gplus-sharePatente US5832240 - ISDN-based high speed communication system
