US5864538A
Expired / Lapsed
US
⏱️ 0.0 years remaining
First-order rate-based flow control with adaptive queue threshold for ATM networks
Assignee: Nokia of America Corp
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Filing: 1996-08-26
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Granted: 1999-01-26
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Expires: 2016-08-26
Abstract
Abstract Novel rate-based flow control methods operate in conjunction with a data communications network. Such networks include a plurality of interconnected nodes, wherein each node is adapted for connection to any of a plurality of sources. The sources send data to, and receive data from, the nodes. The path that data follows in traveling from a first source, through one or more nodes, to a second source, is referred to as a virtual circuit path. Each node includes a processor and an associated memory for storing a data queue of data received from sources. According to one embodiment, referred to as first-order rate-based flow control, a node allocates a data transfer rate to a source based upon the difference between the current queue length at that node and the queue threshold of that node multiplied by a gain. If an appropriate value is calculated and/or empirically determined for the gain, the closed-loop system is asymptotically stable with no persistent oscillation, irrespective of the number of node-to-node connections in a given virtual circuit path, and the round-trip delay of this virtual circuit path. First-order rate-based flow control maintains high node-to-node link utilization and low data loss.
Inventors
- 👤 Song Chong
- 👤 Ramesh Nagarajan
- 👤 Yung-Terng Wang
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 09:49
CPC Classifications
H; H04; H04L; H04L12/00; H04L12/54; H04L12/56; H04L12/5601; H04L12/5602; H04Q; H04Q11/00; H04Q11/04; H04Q11/0428; H04Q11/0478; H04L2012/5629; H04L2012/5631; H04L2012/5636; H04L2012/5678; H04L2012/5681; H04L2012/5682
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
246 words
A first-order rate-based flow control method which operates in conjunction with a data communications network including a plurality of interconnected nodes, wherein each node is adapted for connection to any of a plurality of sources, the sources adapted for sending data to, and receiving data from, the nodes, wherein a path that data follows in traveling from a first source, through one or more nodes, to a second source, is a virtual circuit path, and wherein the each node includes a processor and an associated memory for storing a data queue of data received from the sources, the data queue having a current queue length and being associated with a queue threshold, the method characterized by the steps of: (a) a first node allocating a first data transfer rate to a first source based upon the difference between the current queue length at the first node and the queue threshold of the first node multiplied by a first node gain; the first data transfer rate being allocated by sending a first feedback signal to the first source specifying the first transfer rate; and (b) a second node allocating a second data transfer rate to a second source based upon the difference between the current queue length at the second node and the queue threshold of the second node multiplied by a second node gain; the second data transfer rate being allocated by sending a second feedback signal to the second source specifying the second transfer rate.
Claim 2
Dependent Claim
246 words
A first-order rate-based flow control method which operates in conjunction with a data communications network including a plurality of interconnected nodes, wherein each node is adapted for connection to any of a plurality of sources, the sources adapted for sending data to, and receiving data from, the nodes, wherein a path that data follows in traveling from a first source, through one or more nodes, to a second source, is a virtual circuit path, and wherein the each node includes a processor and an associated memory for storing a data queue of data received from the sources, the data queue having a current queue length and being associated with a queue threshold, the method characterized by the steps of: (a) a first node allocating a first data transfer rate to a first source based upon the difference between the current queue length at the first node and the queue threshold of the first node multiplied by a first node gain; the first data transfer rate being allocated by sending a first feedback signal to the first source specifying the first transfer rate; and (b) a second node allocating a second data transfer rate to a second source based upon the difference between the current queue length at the second node and the queue threshold of the second node multiplied by a second node gain; the second data transfer rate being allocated by sending a second feedback signal to the second source specifying the second transfer rate.
Claim 3
Dependent Claim
65 words
The method of claim 1 further including the step of calculating and/or empirically determining a value for the first node gain and the second node gain such that the data communications network is asymptotically stable with no persistent oscillation, irrespective of the number of node-to-node connections in a given virtual circuit path, and also irrespective of a round-trip delay provided by this virtual circuit path.
Claim 4
Dependent Claim
29 words
The method of claim 2 further including the step of providing fairness in bandwidth allocation among node-to-node connections by weighting the first node gain and the second node gain.
Claim 5
Dependent Claim
75 words
The method of claim 1 further including the step of adaptively changing the queue threshold at each of the nodes along a given virtual circuit path, based upon changes in available bandwidth, and also based upon the establishment and/or discontinuance of source connections at each of the nodes in a given virtual circuit path, thereby providing flow control in a dynamic environment where available bandwidth varies, and node-to-node connections are frequently made and then broken.
References Cited (Backward Citations)
US5457687A
Cited
US5426635A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2002-01-25 | 2002-07-27 | 2003-01-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2006-01-25 | 2006-07-27 | 2007-01-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2010-01-25 | 2010-07-27 | 2011-01-26 | $7700.00 | Window Closed / Lapsed |