Multiplex communications – Wide area network – Packet switching
Patent
1989-06-07
1991-03-12
Olms, Douglas W.
Multiplex communications
Wide area network
Packet switching
370 60, H04J 312, H04Q 1104
Patent
active
049998366
ABSTRACT:
An ISDN network termination unit for connecting a user's bus line connected to a plurality of terminal equipments and a subscriber line extending from an exchanging office receives and transmits a D channel signal from one of the exchanging office and each terminal equipment to the other to thereby establish a data link between them on the D channel. The D channel signal is provided with an identifier code field. In order to establish a data link between the terminal equipments on the D channel without use of the subscriber line and the exchanging office, the ISDN network termination unit is provided with an identifier code holder for holding a predetermined identifier code and a deciding circuit for deciding whether or not the identifier code in the D channel signal from a specific one of the terminal equipment is equal to the predetermined identifier code. When both are equal to each other, the D channel signal is returned by a returning circuit to the terminal equipments through the user's line to thereby establish the data link between the specific terminal equipment and the other terminal equipments through the network termination unit. It may be made that a start flag and a stop flag are additionally detected so as to control the returning circuit.
REFERENCES:
patent: 4792800 (1988-12-01), Fujioka et al.
patent: 4835769 (1989-05-01), Donaghue, Jr. et al.
patent: 4847833 (1989-07-01), Doering et al.
patent: 4935923 (1990-06-01), Shimizu et al.
Chin Wellington
NEC Corporation
Olms Douglas W.
LandOfFree
ISDN network termination unit enabling to establish data link be does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with ISDN network termination unit enabling to establish data link be, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and ISDN network termination unit enabling to establish data link be will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-453126