US4000378A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Data communication system having a large number of terminals
Assignee: Unisys Corp
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Filing: 1975-05-06
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Granted: 1976-12-28
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Expires: 1995-05-06
Abstract
Abstract A large number of terminals are connected to a central computer in a loop utilizing a very high speed transmission medium. A sequential stream of message blocks are provided for transmission by the loop. Each message block includes a first portion specifying a terminal address, and a second portion for specifying information data. Each terminal interrogates the address portion of each message block and responds to its own address by either reading the data portion of the message block or loading into the data portion messages to be transmitted. By generating a continuous stream of message blocks, one for each terminal, and using a randomizing scheme for address generation, it is possible to connect a large number of terminals to a data communications system while maintaining a reasonable response time.
Inventors
- 👤 Lee N. Caplan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 16:00
CPC Classifications
H; H04; H04J; H04J3/00; H04J3/24; H04J3/245; G; G06; G06F; G06F13/00; G06F13/38; G06F13/42; G06F13/4204; G06F13/4208; G06F13/4213; H04L; H04L12/00; H04L12/28; H04L12/42; H04L12/423
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
124 words
A method of communicating with a plurality of terminals connected in a serial loop to a central station, wherein each of said terminals has a unique address, comprising the steps of: randomly generating a first unique address corresponding to said unique address of one of said terminals; generating in the central station a sequential train of message blocks, each of said message blocks having an address portion; supplying said randomly generated unique address to said address portion of one of said generated message blocks; incrementing sequentially said first unique address to provide addresses for the respective message blocks of said sequential train following said one of said message blocks; and transmitting from said central station to said loop said sequential train of message blocks.
Claim 2
Independent Claim
124 words
A method of communicating with a plurality of terminals connected in a serial loop to a central station, wherein each of said terminals has a unique address, comprising the steps of: randomly generating a first unique address corresponding to said unique address of one of said terminals; generating in the central station a sequential train of message blocks, each of said message blocks having an address portion; supplying said randomly generated unique address to said address portion of one of said generated message blocks; incrementing sequentially said first unique address to provide addresses for the respective message blocks of said sequential train following said one of said message blocks; and transmitting from said central station to said loop said sequential train of message blocks.
Claim 3
Dependent Claim
34 words
The method of claim 1 wherein said step of generating a plurality of message blocks additionally includes generating each of said terminal addresses starting with a new random number for each complete message cycle.
Claim 4
Independent Claim
99 words
A system for communicating with a plurality of terminals connected in a serial loop, wherein each terminal is assigned a unique address comprising: first means for randomly generating a first unique address corresponding to said unique address of one of said terminals; second means for generating a sequential train of message blocks, each of said message blocks having an address portion; and third means coupled to said first means and said second means for incrementing sequentially said unique address generated by said first means to provide address information for said address portion of said generated train of message blocks.
Claim 5
Independent Claim
99 words
A system for communicating with a plurality of terminals connected in a serial loop, wherein each terminal is assigned a unique address comprising: first means for randomly generating a first unique address corresponding to said unique address of one of said terminals; second means for generating a sequential train of message blocks, each of said message blocks having an address portion; and third means coupled to said first means and said second means for incrementing sequentially said unique address generated by said first means to provide address information for said address portion of said generated train of message blocks.
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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) | 1979-12-28 | 1980-06-28 | 1980-12-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-12-28 | 1984-06-28 | 1984-12-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-12-28 | 1988-06-28 | 1988-12-28 | $7700.00 | Window Closed / Lapsed |