Multiplex communications – Wide area network – Packet switching
Patent
1994-03-21
1996-01-30
Kizou, Hassan
Multiplex communications
Wide area network
Packet switching
370 601, H04L 1256
Patent
active
054886066
ABSTRACT:
An ATM (asynchronous transfer mode) exchange has a buffer for system #0 and a buffer for system #1 providing P-MEM's for storing data including an A bit and for a VCI/VPI currently in use is set to "1'. Upon detecting a switchover between the systems, every B bit is reset to "0". When the exchange while changing from a master to a slave receives a cell having a slave indication and while changing from a slave to a master it receives a cell having a master indication, respective systems rewrite B bits for VCI/VPI's of respective cells to "1". In the meantime, each of the P-MEM's calculates exclusive "OR" operations between the A bit and the B bit for every VCI/VPI, and further obtains a disjunction among all the exclusive "OR" operations thus obtained. Then, when both P-MEM's obtain "0" for their respective disjunctions, cells are read out from one of the buffers in the system changing from a slave to a master. This enables the ATM exchange having a switch duplexed by mutually asynchronous active and backup systems to switchover the systems without causing a cell to be duplicated or lost.
REFERENCES:
patent: 5072440 (1991-12-01), Isono et al.
patent: 5274633 (1993-12-01), Kato et al.
patent: 5283782 (1994-02-01), Takase et al.
patent: 5301184 (1994-04-01), Uriu et al.
Hajikano Kazuo
Kakuma Satoshi
Murayama Masami
Okuyama Yuzo
Yoshimura Shuji
Fujitsu Limited
Kizou Hassan
LandOfFree
Procedure for switching-over systems does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Procedure for switching-over systems, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Procedure for switching-over systems will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-160970