Excavating
Patent
1986-05-14
1988-08-23
Atkinson, Charles E.
Excavating
379 5, H04B 346
Patent
active
047665947
ABSTRACT:
A digital network system having an arrangement for testing a digital subscriber line includes a switching device, an exchange terminal device as a subscriber circuit connected with the switching device, a subscriber line connected with the exchange terminal device, a network terminal device at a subscriber's side connected between the subscriber line and terminal equipment devices. The network terminal device includes a turn-around portion for forming a turn-around loop through which the turning-around of a signal to the subscriber line connected with the network termination device is carried out, and a discrimination portion for detecting that data transmission can be carried out and cancelling the formation of the turn-around loop. The turn-around loop is formed when a frame synchronization bit signal from the exchange terminal device is received by the network terminal device and cancelled when the discrimination portion detects that data transmission can be carried out. Communication for either a monitoring of transmission or a bit error testing can be carried out between the network terminal device and the switching device while the turn-around loop is formed, and data transmission between the exchange terminal device and the terminal equipment devices can be carried out after the turn-around loop is cancelled.
REFERENCES:
patent: 3743938 (1973-07-01), Davis
patent: 4039751 (1977-08-01), Couturier et al.
patent: 4242750 (1980-12-01), Finck et al.
patent: 4271513 (1981-06-01), Maejima et al.
patent: 4402075 (1983-08-01), Bargeton et al.
patent: 4425662 (1984-01-01), Jeandot
patent: 4529979 (1985-07-01), Kusama et al.
patent: 4547633 (1985-10-01), Szechenyl
patent: 4564933 (1986-01-01), Hirst
patent: 4575847 (1986-03-01), Fallwell, Jr. et al.
Ogawa Yasunori
Shimozono Ryoji
Tanaka Yasuo
Tsutsumi Kenji
Atkinson Charles E.
Fujitsu Limited
LandOfFree
Digital network system having arrangement for testing digital su does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Digital network system having arrangement for testing digital su, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Digital network system having arrangement for testing digital su will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-840312