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US4296492A Expired / Lapsed US ⏱️ 0.0 years remaining

Continuity verification arrangement

Assignee: AT&T Inc
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Filing: 1979-12-26
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Granted: 1981-10-20
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Expires: 1999-12-26
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Abstract

Abstract A time division switching system having distributed control processors is disclosed. The switching system includes time-slot interchange units having associated subscriber sets and a time-shared space division network for interconnecting the time-slot interchange units. Each of the time-slot interchange units and the time-shared space division network are controlled by separate control processors. In response to called subscriber set identifying information from a calling subscriber set, the control processor associated with the time-shared space division network completes the communication path through the time-shared space division network to connect the time-slot interchange units associated with the calling and called subscriber sets. The control processors in the time-slot interchange units then determine if communication path continuity is present between them before the subscriber sets are connected to the communication path through the time-slot interchange units. Additionally, arrangements are included for detecting loss of continuity in the communication path.

Inventors

  • 👤 Edward H. Hafer

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-24 12:30
CPC Classifications
H; H04; H04Q; H04Q11/00; H04Q11/04; H04Q11/0407

Claims Analysis

Total Claims: 13
Claim 1
Independent Claim 148 words
A continuity verification arrangement for verifying continuity of communication paths through a time division switching means comprising a first communication unit, a second communication unit, a time division switching means comprising means for generating communication path identity signals and means responsive to said communication path identity signals for completing a communication path between said first and said second communication units characterized in that said time division switching means further comprises means for transmitting to said first and said second communication units said communication path identity signals; said first communication unit comprises means responsive to said communication path identity signals for transmitting a unique character on said communication path; and said second communication unit comprises receive means for receiving from said communication path said unique character transmitted by said originating unit, and continuity indicating means for generating continuity signals when said unique character is received on said communication path.
Claim 2
Dependent Claim 148 words
A continuity verification arrangement for verifying continuity of communication paths through a time division switching means comprising a first communication unit, a second communication unit, a time division switching means comprising means for generating communication path identity signals and means responsive to said communication path identity signals for completing a communication path between said first and said second communication units characterized in that said time division switching means further comprises means for transmitting to said first and said second communication units said communication path identity signals; said first communication unit comprises means responsive to said communication path identity signals for transmitting a unique character on said communication path; and said second communication unit comprises receive means for receiving from said communication path said unique character transmitted by said originating unit, and continuity indicating means for generating continuity signals when said unique character is received on said communication path.
Claim 3
Dependent Claim 60 words
The continuity verification arrangement in accordance with claim 1 further characterized in that said first and said second communication units each comprise means for transmitting and receiving data words; and said second communication means comprises means responsive to said continuity signals for connecting said means for transmitting and receiving data words of said second communication means to said communication path.
Claim 4
Dependent Claim 51 words
The continuity verification arrangement in accordance with claim 1 further characterized in that said second communication unit comprises means for generating discontinuity signals when said unique character is not received by said receive means within a predetermined period of time after said second communication means receives said communication path identity signals.
Claim 5
Dependent Claim 46 words
The continuity verification arrangement in accordance with claim 2 further characterized in that said second communication means further comprises means responsive to said continuity signals for generating discontinuity signals when no unique characters are received by said receive means after said continuity signals have been generated.
Claim 6
Dependent Claim 46 words
The continuity verification arrangement in accordance with claim 4 further characterized in that said second communication means comprises means responsive to said discontinuity signals for removing the connection between said communication path and said means for transmitting and receiving data words of said second communication means.
Claim 7
Dependent Claim 40 words
The continuity verification arrangement in accordance with claims 3 or 4 further characterized in that said second communication means comprises means responsive to said discontinuity signals for transmitting a control message indicative of discontinuity to said time division switching means.
Claim 8
Dependent Claim 70 words
The continuity verification arrangement in accordance with claim 1 wherein said communication path comprises a recurring series of time slots from said first communication unit to said second communication unit further characterized in that said means for transmitting a unique character comprises means responsive to said communication path identity signals for transmitting said unique character during each time slot of said recurring series of time slots comprising said communication path.
Claim 9
Dependent Claim 73 words
The continuity verification arrangement in accordance with claim 7, wherein each of said time slots comprises a plurality of bit positions, characterized in that said means for transmitting a unique character comprises means responsive to said communication path identity signals for transmitting a unique character comprising a predetermined binary digit in a predetermined one of said bit positions during each time slot of said recurring series of time slots comprising said communication path.
Claim 10
Dependent Claim 259 words
A time division switching system comprising a first subscriber set for generating data words representinhg subscriber signals, a second subscriber set for generating data words representing subscriber signals and routing information identifying said first subscriber set, first time-slot interchange means connected to said first subscriber set, second time-slot interchange means connected to said second subscriber set, control means for receiving said routing information and, for generating communication path identity signals, a time-shared space division network for receiving said communication path identity signals and for completing a communication path between said first and said second time-slot interchange means, said communication path comprising a first recurring series of time slots from said first to said second time-slot interchange means and a second recurring series of time slots from said second to said first time-slot interchange means characterized in that said control means comprises means for transmitting communication path identity signals to said first and said second time-slot interchange means; said second time-slot interchange means comprises means responsive to said communication path identity signals for transmitting a unique character in each time slot of said second recurring series of time slots; and said first time-slot interchange means comprises first means for receiving said unique characters from the time slots of said second recurring series of time slots and, means responsive to said unique characters for transmitting data words from said first subscriber set in the time slots of said first recurring series of time slots and for receiving data words from the time slots of said second recurring series of time slots.
Claim 11
Dependent Claim 259 words
A time division switching system comprising a first subscriber set for generating data words representinhg subscriber signals, a second subscriber set for generating data words representing subscriber signals and routing information identifying said first subscriber set, first time-slot interchange means connected to said first subscriber set, second time-slot interchange means connected to said second subscriber set, control means for receiving said routing information and, for generating communication path identity signals, a time-shared space division network for receiving said communication path identity signals and for completing a communication path between said first and said second time-slot interchange means, said communication path comprising a first recurring series of time slots from said first to said second time-slot interchange means and a second recurring series of time slots from said second to said first time-slot interchange means characterized in that said control means comprises means for transmitting communication path identity signals to said first and said second time-slot interchange means; said second time-slot interchange means comprises means responsive to said communication path identity signals for transmitting a unique character in each time slot of said second recurring series of time slots; and said first time-slot interchange means comprises first means for receiving said unique characters from the time slots of said second recurring series of time slots and, means responsive to said unique characters for transmitting data words from said first subscriber set in the time slots of said first recurring series of time slots and for receiving data words from the time slots of said second recurring series of time slots.
Claim 12
Dependent Claim 116 words
The time division switching system in accordance with claim 9 further characterized in that said first time-slot interchange means comprises means responsive to said communication path identity signals for transmitting a unique character in each time slot of said first recurring series of time slots; and said second time-slot interchange means comprises second means for receiving said unique characters from the time slots of said first recurring series of time slots and means responsive to said unique characters for transmitting data words from said second subscriber set in the time slots of said second recurring series of time slots and for receiving data words from the time slots of said first recurring series of time slots.
Claim 13
Dependent Claim 115 words
The time division switching system in accordance with claim 9 further characterized in that said first time-slot interchange means comprises means for transmitting to said control means a control message indicative of discontinuity, when said unique characters are not received by said first means for receiving within a predetermined period of time after said first time-slot interchange means receives said communication path identity signals; and said second time-slot interchange means comprises means for transmitting to said control means a control message indicative of discontinuity, when said unique characters are not received by said second means for receiving within a predetermined period of time after said second time-slot interchange means receives said communication path identity signals.

References Cited (Backward Citations)

US3639904A Cited
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US3909562A Cited
US4064369A Cited
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USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1984-10-19 1985-04-20 1985-10-20 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1988-10-19 1989-04-20 1989-10-20 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1992-10-19 1993-04-20 1993-10-20 $7700.00 Window Closed / Lapsed

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