US4954965A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Enhanced frame utilization for CSMA/CD communication protocol
Assignee: International Business Machines Corp
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Filing: 1989-02-09
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Granted: 1990-09-04
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Expires: 2009-02-09
Abstract
Abstract In a CSMA/CD communication protocol, data to be sent from one device on a communication network to another is put into frames, or predetermined sized pieces of information. One of the fields in a frame, the pad field, is used to make the total size of the frame large enough to ensure that a collision anywhere in the network with another frame is detected by the senders. The pad field is further used to identify when a data record will be continued in the next frame and also to identify when multiple data records are being sent in the same frame.
Inventors
- 👤 John M. Johnson
- 👤 James A. Rocke
- 👤 Divakara K. R. Udupa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 02:25
CPC Classifications
H; H04; H04L; H04L12/00; H04L12/28; H04L12/40; H04L12/407; H04L12/413
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
147 words
A device for transferring data between nodes coupled to a network having a carrier sense multiple access/collision detect protocol for such data transfer, the device at each node comprising: means for identifying data records to be transferred to another node; means coupled to the identifying means for generating frames containing data from the data records to be transmitted; means coupled to the frame generating means for determining when data from a single record is put into more than one different frame to be transmitted: means coupled to the frame generating means for inserting in said frames indications to identify the different frames which contain data from the single record; means coupled to said frame generating means for inserting in said frames indications to differentiate between data records contained in the same frame; and means coupled to the identifying means for transmitting said frames to the other node.
Claim 2
Independent Claim
147 words
A device for transferring data between nodes coupled to a network having a carrier sense multiple access/collision detect protocol for such data transfer, the device at each node comprising: means for identifying data records to be transferred to another node; means coupled to the identifying means for generating frames containing data from the data records to be transmitted; means coupled to the frame generating means for determining when data from a single record is put into more than one different frame to be transmitted: means coupled to the frame generating means for inserting in said frames indications to identify the different frames which contain data from the single record; means coupled to said frame generating means for inserting in said frames indications to differentiate between data records contained in the same frame; and means coupled to the identifying means for transmitting said frames to the other node.
Claim 3
Independent Claim
158 words
A device for transferring data between nodes coupled to a network having a carrier sense multiple access/collision detect protocol for such data transfer, the device at each node comprising: means for identifying data records to be transferred to another node; means coupled to the identifying means for generating frames containing data from the data records to be transmitted; means coupled to the frame generating means for inserting a more bit in a pad field of a frame to indicate that there is more data in a record; means coupled to the frame generating means for inserting a record number in the pad field of a frame to indicate an ordering of data in a record; means coupled to the network for receiving at least one frame from the network; means coupled to the frame receiving means for assembling a record from data contained in multiple frames, each of said frames having a more bit and a record number.
Claim 4
Independent Claim
158 words
A device for transferring data between nodes coupled to a network having a carrier sense multiple access/collision detect protocol for such data transfer, the device at each node comprising: means for identifying data records to be transferred to another node; means coupled to the identifying means for generating frames containing data from the data records to be transmitted; means coupled to the frame generating means for inserting a more bit in a pad field of a frame to indicate that there is more data in a record; means coupled to the frame generating means for inserting a record number in the pad field of a frame to indicate an ordering of data in a record; means coupled to the network for receiving at least one frame from the network; means coupled to the frame receiving means for assembling a record from data contained in multiple frames, each of said frames having a more bit and a record number.
Claim 5
Independent Claim
111 words
A device for transferring data between nodes coupled to a network having a carrier sense multiple access/collision detect protocol for such data transfer, the device at each node comprising: means for identifying data records to be transferred to another node; means coupled to the identifying means for generating frames containing data from the data records to be transmitted; means coupled to the frame generating means for detecting short record; means coupled to the frame generating means for combining short records in a frame to be transmitted; and means coupled to the frame generating means for inserting representations of record lengths of said combined records in a pad field of said frame.
Claim 6
Independent Claim
111 words
A device for transferring data between nodes coupled to a network having a carrier sense multiple access/collision detect protocol for such data transfer, the device at each node comprising: means for identifying data records to be transferred to another node; means coupled to the identifying means for generating frames containing data from the data records to be transmitted; means coupled to the frame generating means for detecting short record; means coupled to the frame generating means for combining short records in a frame to be transmitted; and means coupled to the frame generating means for inserting representations of record lengths of said combined records in a pad field of said frame.
Claim 7
Dependent Claim
62 words
The device of claim 3 further comprising: means coupled to the network for receiving at least one frame from the network; means coupled to the frame receiving means for detecting if there are record length representations in the pad field; and means coupled to the frame receiving means for assembling records in a received frame in accordance with the record length representations.
Claim 8
Dependent Claim
15 words
The device of claim 4 wherein up to 4 records are transmitted to a frame.
Claim 9
Dependent Claim
21 words
The device of claim 5 wherein the record length is compatible with a single line of text displayable on a CRT.
Claim 10
Dependent Claim
22 words
The device of claim 5 wherein the record length is compatible with a single line of text printable by a printing device.
Claim 11
Independent Claim
211 words
A device for transferring data between nodes coupled to a network having a carrier sense multiple access/collision detect protocol for such data transfer, the device at each node comprising: means for identifying data records to be transferred to another node; means coupled to the identifying means for generating frames containing data from the data records to be transmitted; means coupled to the frame generating means for inserting a more bit in a pad field of a frame to indicate that there is more data in a record; means coupled to the frame generating means for inserting a record number in the pad field of a frame to indicate an ordering of data in a record; means coupled to the network for receiving one or more frames from the network; means coupled to the frame receiving means for assembling a record from data contained in multiple frames, each of said frames having a more bit and a record number. means coupled to the frame generating means for detecting short records; means coupled to the frame generating means for combining short records in a frame to be transmitted; and means coupled to the frame generating means for inserting representation of record lengths of said combined records in a pad field of said frame.
Claim 12
Independent Claim
211 words
A device for transferring data between nodes coupled to a network having a carrier sense multiple access/collision detect protocol for such data transfer, the device at each node comprising: means for identifying data records to be transferred to another node; means coupled to the identifying means for generating frames containing data from the data records to be transmitted; means coupled to the frame generating means for inserting a more bit in a pad field of a frame to indicate that there is more data in a record; means coupled to the frame generating means for inserting a record number in the pad field of a frame to indicate an ordering of data in a record; means coupled to the network for receiving one or more frames from the network; means coupled to the frame receiving means for assembling a record from data contained in multiple frames, each of said frames having a more bit and a record number. means coupled to the frame generating means for detecting short records; means coupled to the frame generating means for combining short records in a frame to be transmitted; and means coupled to the frame generating means for inserting representation of record lengths of said combined records in a pad field of said frame.
Claim 13
Dependent Claim
24 words
The device of claim 8 wherein the more bit and record number comprise a single predetermined byte of the pad field of each frame.
Claim 14
Dependent Claim
55 words
The device of claim 8 further comprising: means coupled to the frame generating means for indicating optimal frame size; means coupled to the frame generating means for combining records to maintain an optimal size frame; and means coupled to the frame generating means for breaking records into multiple frames to maintain an optimal size frame.
Claim 15
Dependent Claim
20 words
The device of claim 8 wherein the representations of field length each comprise a predetermined byte of the pad field.
References Cited (Backward Citations)
US4543654A
Cited
US4688035A
Cited
US4757460A
Cited
US4745559A
Cited
US4750137A
Cited
US4771391A
Cited
US4837679A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-09-03 | 1994-03-05 | 1994-09-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-09-03 | 1998-03-05 | 1998-09-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-09-03 | 2002-03-05 | 2002-09-04 | $7700.00 | Window Closed / Lapsed |