US3680056A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Use equalization on closed loop message block transmission systems
Assignee: AT&T Inc
•
Filing: 1970-10-08
•
Granted: 1972-07-25
•
Expires: 1990-10-08
Abstract
Abstract A closed loop transmission system is described in which a plurality of stations have access to the loop to write messages into and read messages from standard-sized message blocks transmitted around the loop. One station provides regeneration of all message blocks. In order to prevent one or more stations from monopolizing the use of the transmission loop, a field is reserved in each message block for setting flags each time a station desires to transmit a message but is unable to do so because the message block is filled. Originating stations are thereafter prevented from initiating a second message until all other requesting stations have been served, as indicated by the flagged field in the message block.
Inventors
- 👤 Walter Joseph Kropfl
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 04:56
CPC Classifications
H; H04; H04L; H04L12/00; H04L12/28; H04L12/42; H04L12/427; H04L12/43
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
95 words
A closed loop digital transmission system comprising a closed loop transmission line, a plurality of access stations for writing digital messages into, and reading digital messages from, said line, each said message including a plurality of use allocation bits, means at each of said stations for marking said allocation bits for each of said stations attempting to write a digital message onto said line when said line already contains a digital message, and means at each of said stations for disabling the writing of a second message until all other of said stations are serviced.
Claim 2
Dependent Claim
95 words
A closed loop digital transmission system comprising a closed loop transmission line, a plurality of access stations for writing digital messages into, and reading digital messages from, said line, each said message including a plurality of use allocation bits, means at each of said stations for marking said allocation bits for each of said stations attempting to write a digital message onto said line when said line already contains a digital message, and means at each of said stations for disabling the writing of a second message until all other of said stations are serviced.
Claim 3
Dependent Claim
33 words
The closed loop digital transmission system according to claim 1 further comprising a regeneration station for regenerating digital messages on said loop, and means at said regeneration station for altering said allocation bits.
Claim 4
Dependent Claim
68 words
The closed loop digital transmission system according to claim 2 wherein said means for marking said allocation bits includes means for setting a first of said bits to a preselected logical state, and said altering means at said regeneration station includes means for setting a second one of said bits to the logical value of said first bit, and setting said first bit to the opposite logical value.
Claim 5
Dependent Claim
42 words
The closed loop digital transmission system according to claim 1 wherein said disabling means comprises storage means for registering the transmission of a message block, and means responsive to said storage means for blocking further transmissions from that station registering said transmission.
Claim 6
Dependent Claim
107 words
A digital station for closed loop transmission systems comprising a shifting register in series with said loop for serially reading digital data from said loop and serially writing said digital data into said loop, parallel data access means for writing data into and reading data from said register, control signal detection means responsive to signals in said register for controlling the operation of said data access means, means included in said signal detection means for detecting a condition indicating that another station is seeking to write data into said loop, and means for disabling said data access means until said other station completes a data writing operation.
Claim 7
Dependent Claim
107 words
A digital station for closed loop transmission systems comprising a shifting register in series with said loop for serially reading digital data from said loop and serially writing said digital data into said loop, parallel data access means for writing data into and reading data from said register, control signal detection means responsive to signals in said register for controlling the operation of said data access means, means included in said signal detection means for detecting a condition indicating that another station is seeking to write data into said loop, and means for disabling said data access means until said other station completes a data writing operation.
Claim 8
Dependent Claim
79 words
The digital station according to claim 5 wherein said digital data is in the form of a message block of a plurality of words of equal length separated by guard signals, the initial ones of said words comprising control signals, and said disabling means comprises a fLag register, means for setting said flag register when a message is written into said loop, and means for resetting said flag register when selected portions of initial words have a preselected value.
Claim 9
Dependent Claim
39 words
The digital station according to claim 6 wherein one of said initial words includes a monopoly prevention field, and means for marking said monopoly prevention field in response to an attempt to write data into an already-filled message block.
Claim 10
Dependent Claim
25 words
The digital station according to claim 7 further including means for altering said monopoly prevention field on successive transits of said field around said loop.
Claim 11
Dependent Claim
89 words
A data transmission system comprising a closed loop transmission line, a synchronizing repeater in said loop, a plurality of stations on said loop for inserting digital message blocks into, and removing said message blocks from, said loop, means at said stations for marking each said message whenever a nonoriginating one of said stations requests the use of said loop, and means responsive to markings in said message for preventing an originating station from inserting a message block into said loop again until all of said requests have been satisfied.
Claim 12
Dependent Claim
89 words
A data transmission system comprising a closed loop transmission line, a synchronizing repeater in said loop, a plurality of stations on said loop for inserting digital message blocks into, and removing said message blocks from, said loop, means at said stations for marking each said message whenever a nonoriginating one of said stations requests the use of said loop, and means responsive to markings in said message for preventing an originating station from inserting a message block into said loop again until all of said requests have been satisfied.
Claim 13
Dependent Claim
23 words
The data transmission system according to claim 9 further including means for modifying said markings each time a message passes said synchronizing repeater.
References Cited (Backward Citations)
US3411143A
Cited
US3456242A
Cited
US3483329A
Cited
US3517130A
Cited
US3480914A
Cited
US3445822A
Cited
US3544976A
Cited
GB1182363A
Cited
US3597549A
Cited
US3597549B1
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-07-25 | 1976-01-24 | 1976-07-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-07-25 | 1980-01-24 | 1980-07-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-07-25 | 1984-01-24 | 1984-07-25 | $7700.00 | Window Closed / Lapsed |