05488606 is referenced by 51 patents and cites 4 patents.

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.

Title
Procedure for switching-over systems
Application Number
8/216149
Publication Number
5488606
Application Date
March 21, 1994
Publication Date
January 30, 1996
Inventor
Yuzo Okuyama
Kanagawa
JP
Masami Murayama
Kanagawa
JP
Kazuo Hajikano
Kanagawa
JP
Shuji Yoshimura
Kanagawa
JP
Satoshi Kakuma
Kanagawa
JP
Assignee
Fujitsu
JP
IPC
H04L 12/56
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