ISDN user-network interface system
Patent 5309440 Issued on May 3, 1994. Estimated Expiration Date: 
September 3, 2012. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
September 3, 2012. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent ReferencesISDN subscriber terminal control system Local communication system among ISDN terminal equipments Passive bus communication for ISDN Repeater for extending local area networks Simple adapter for multiplexing ISDN terminals Network terminating terminal apparatus for integrated services digital network Patent #: 5204860 InventorsAssigneeApplicationNo. 940040 filed on 09/03/1992US Classes:370/420, For connecting plural subscribers to a network (i.e., network termination)370/524Using a dedicated signaling channel (i.e., D-channel)ExaminersPrimary: Olms, Douglas W.Assistant: Blum, Russell W. Attorney, Agent or FirmInternational ClassH04J 003/06Foreign Application Priority Data1991-09-06 JPAbstractAn ISDN-user-network interface system comprising an interface buffer and an interface adapter. The interface buffer provided between an ISDN network terminal equipment and a terminal equipment to receive an up-signal frame transmitted from said terminal equipment to said network terminal equipment, to store said up-signal frame, and to transmit said stored up-signal frame at a timing when said network terminal equipment is capable of detecting the synchronization of said up-signal frame. The interface adapter provided between said ISDN network terminal equipment and said terminal equipment, to receive an up-signal frame transmitted from said terminal equipment to said network terminal equipment, to detect D-channel bits of said up-signal frame, to transmit said up-signal frame to said network terminal equipment, to copy said detected D-channel bits into echo channel bits of a down-signal frame from said net-work terminal equipment to said terminal equipment received immediately after the transmission of said up-signal frame, and to transmit said down-signal frame to said terminal equipment. | |
