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US3984641A
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US
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System for switching and safeguarding data in time-division multiplex switching networks
Assignee: International Standard Electric Corp
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Filing: 1974-07-30
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Granted: 1976-10-05
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Expires: 1994-07-30
Abstract
Abstract A system is disclosed for safeguarding data against slip in signals occurring in interfaces between exchanges employing different exchange clock rates. Suitably connected storage arrangements cause the instants of slip compensation in both directions of transmission to coincide. In this way, omission of a signal in one direction of transmission results in a signal being inserted in the other direction and prevents the loss of data.
Inventors
- 👤 Hinrich Ruyter
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 13:47
CPC Classifications
H; H04; H04J; H04J3/00; H04J3/02; H04J3/06; H04J3/062; H04J3/0626; H04L; H04L12/00; H04L12/50; H04L12/52; H04L12/525; H04L25/00; H04L25/02; H04L25/05; H04Q; H04Q11/00; H04Q11/04
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
166 words
A system for switching and safeguarding data in time-division-multiplex switching networks in which both the two transmission paths between two neighboring time-division-multiplex exchanges, which paths are provided for one direction of transmission each, and a first input circuit to one exchange, which first input circuit is connected to the transmission paths and represents a synchronous group, are operated at the clock rate of said one exchange, and in which a second input circuit lying opposite said first input circuit and representing an asynchronous group is operated so that read and write operations to or from the transmission paths take place at the clock rate of said one exchange, while read and write operations to or from the switching grid of of the other exchange take place at the clock rate of the other exchange, wherein the improvement comprises means in the asynchronous group to correlate slips in the timing of signals on the two transmission paths and particularly to cause said slips to coincide in time.
Claim 2
Independent Claim
166 words
A system for switching and safeguarding data in time-division-multiplex switching networks in which both the two transmission paths between two neighboring time-division-multiplex exchanges, which paths are provided for one direction of transmission each, and a first input circuit to one exchange, which first input circuit is connected to the transmission paths and represents a synchronous group, are operated at the clock rate of said one exchange, and in which a second input circuit lying opposite said first input circuit and representing an asynchronous group is operated so that read and write operations to or from the transmission paths take place at the clock rate of said one exchange, while read and write operations to or from the switching grid of of the other exchange take place at the clock rate of the other exchange, wherein the improvement comprises means in the asynchronous group to correlate slips in the timing of signals on the two transmission paths and particularly to cause said slips to coincide in time.
Claim 3
Dependent Claim
73 words
The invention according to claim 1, in which the means in the asynchronous group includes two storage means identical in construction, with each storage means alotted to one direction of transmission, and both storage means are coupled together in such a manner that the sum of the delay periods of an incoming data item and of the associated outgoing data item is equal to one frame period or to an integral multiple thereof.
Claim 4
Dependent Claim
58 words
The invention as claimed in claim 1, in which the means in the asynchronous group include main storage means whose locations are available to both incoming and outgoing data items, with the sum of the delay periods of an incoming (outgoing) and outgoing (incoming) data item being equal to one frame period or to an integral multiple thereof.
Claim 5
Dependent Claim
54 words
The invention as claimed in claim 1, in which the means in the asynchronous group includes a main storage alotted to both directions of transmission, an auxiliary storage, and a direct path which are so controlled that delays in the switching grid of one exchange are included in the sum of the delay periods.
Claim 6
Dependent Claim
42 words
A system for switching and safeguarding data in time-division-multiplex switching networks according to claim 3, in which a signal having passed from one transmission path to the other transmission path as a result of slip is available to be detected and extracted.
Claim 7
Dependent Claim
63 words
A system for switching and safeguarding data in time-division-multiplex switching networks according to claim 5, in which the signals on one transmission path differ from the signals on the other transmission path in such a manner that a signal having passed from one transmission path to the other as a result of slip can be recognized there as being extraneous and then suppressed.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-10-05 | 1980-04-05 | 1980-10-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-10-05 | 1984-04-05 | 1984-10-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-10-05 | 1988-04-05 | 1988-10-05 | $7700.00 | Window Closed / Lapsed |