US5430710A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Order preserving transmission of data streams
Assignee: International Business Machines Corp
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Filing: 1992-08-14
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Granted: 1995-07-04
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Expires: 2012-08-14
Abstract
Abstract Described are methods which preserve the order of the data frames within a data stream if the data stream is switched from one link to another. The first method achieves the order preservation by numbered switch frames that have to be exchanged between the nodes before the link switching is actually performed. In the second method, the switching is only prepared by exchanging special frames which indicate "clean" links. Actual switching takes place by just using an already prepared, i.e., "clean" link.
Inventors
- 👤 Lothar Mueller
- 👤 Rainer Oechsle
- 👤 Hong L. Truong
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 08:49
CPC Classifications
H; H04; H04L; H04L45/00; H04L45/24; H04L45/245; H04L41/00; H04L41/08; H04L41/0803; H04L41/0813; H04L41/0816; H04L41/34; H04L47/00; H04L47/10; H04L47/34; H04L9/00; H04L9/40; Y; Y02; Y02D; Y02D30/00; Y02D30/50
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
225 words
Method for link switching when transmitting a data stream between two nodes (1 and 2, 11 and 12) of a network such that the order within the data stream is preserved, said two nodes being connected by at least two parallel links (link 1 . . . link n) , of which only one is currently active, the method comprising the steps of: a. generating a switch request in the sending node (sender 1, 11); b. attaching a sequence number to said switch request; c. transmitting said switch request with its sequence number from the sending node to the receiving node (receiver 2, 12) over at least one currently inactive link, d. determining, in the receiving node (2, 12), whether a received switch request carries a higher sequence number than a switch request received before and is thus acceptable, e. if so, sending to the sending node (1, 11) over said currently inactive link a switch response with the sequence number of said received switch request; f. determining, in the sending node (1, 11), when receiving a switch response, whether its sequence number matches the sequence number sent with the last switch request and is thus acceptable; and g. depending on the result of the determining step f, activating an inactive link to transmit the data stream from the sending node to the receiving node.
Claim 2
Dependent Claim
225 words
Method for link switching when transmitting a data stream between two nodes (1 and 2, 11 and 12) of a network such that the order within the data stream is preserved, said two nodes being connected by at least two parallel links (link 1 . . . link n) , of which only one is currently active, the method comprising the steps of: a. generating a switch request in the sending node (sender 1, 11); b. attaching a sequence number to said switch request; c. transmitting said switch request with its sequence number from the sending node to the receiving node (receiver 2, 12) over at least one currently inactive link, d. determining, in the receiving node (2, 12), whether a received switch request carries a higher sequence number than a switch request received before and is thus acceptable, e. if so, sending to the sending node (1, 11) over said currently inactive link a switch response with the sequence number of said received switch request; f. determining, in the sending node (1, 11), when receiving a switch response, whether its sequence number matches the sequence number sent with the last switch request and is thus acceptable; and g. depending on the result of the determining step f, activating an inactive link to transmit the data stream from the sending node to the receiving node.
Claim 3
Dependent Claim
53 words
Method according to claim 1, wherein the receiver (2) switches to said currently inactive link upon determining that a received (switch) request is acceptable, and the sender (1) switches to said currently inactive link upon determining that a received response is acceptable, thus effectively switching the data transmission to said currently inactive link.
Claim 4
Dependent Claim
33 words
Method according to claim 2, wherein the sending node (1) continues sending data over the currently active link until the sending node receives the switching response and switches to the currently inactive link.
Claim 5
Dependent Claim
37 words
Method according to claim 2, wherein the sending node (1), upon sending the request over the currently inactive link, suspends sending data and, upon receiving an acceptable response, resumes sending data over the so far inactive link.
Claim 6
Dependent Claim
224 words
Method for link switching when transmitting a data stream between two nodes (1 and 2, 11 and 12) of a network such that the order within the data stream is preserved, said two nodes being connected by at least two parallel links (link 1 . . . link n), of which only one is currently active, the method comprising the steps of: a. generating a sweep request in the sending node (sender 1, 11); b. attaching a sequence number to said sweep request; c. transmitting said sweep request with its sequence number from the sending node to the receiving node (receiver 2, 12) over at least one currently inactive link, d. determining, in the receiving node (2, 12), whether a received sweep request carries a higher sequence number than a sweep request received before and is thus acceptable, e. if so, sending to the sending node (1, 11) over said currently inactive link a sweep response with the sequence number of said received sweep request; f. determining, in the sending node (1, 11), when receiving a sweep response, whether its sequence number matches the sequence number sent with the last sweep request and is thus acceptable; and g. depending on the result of the determining step f, activating an inactive link to transmit the data stream from the sending node to the receiving node.
Claim 7
Dependent Claim
224 words
Method for link switching when transmitting a data stream between two nodes (1 and 2, 11 and 12) of a network such that the order within the data stream is preserved, said two nodes being connected by at least two parallel links (link 1 . . . link n), of which only one is currently active, the method comprising the steps of: a. generating a sweep request in the sending node (sender 1, 11); b. attaching a sequence number to said sweep request; c. transmitting said sweep request with its sequence number from the sending node to the receiving node (receiver 2, 12) over at least one currently inactive link, d. determining, in the receiving node (2, 12), whether a received sweep request carries a higher sequence number than a sweep request received before and is thus acceptable, e. if so, sending to the sending node (1, 11) over said currently inactive link a sweep response with the sequence number of said received sweep request; f. determining, in the sending node (1, 11), when receiving a sweep response, whether its sequence number matches the sequence number sent with the last sweep request and is thus acceptable; and g. depending on the result of the determining step f, activating an inactive link to transmit the data stream from the sending node to the receiving node.
Claim 8
Dependent Claim
132 words
Method according to claim 5, wherein receipt of an acceptable request over a currently inactive link by the receiver (12) indicates to the receiver that this particular link is "clean", receipt of an acceptable response over a currently inactive link by the sending node (11) indicates to the sending node that this particular link is "clean", the sending node (11) effectively switches data stream transmission to any one of the inactive links at any time after the sending node has identified this particular link as "clean" and, upon receiving data from a "clean", inactive link, the receiver (12) effectively switches data stream reception to said inactive link, upon establishing data stream transmission over said inactive link, indicating to the sender and to the receiver that all other links are no more "clean".
Claim 9
Dependent Claim
45 words
Method according to claim 6, wherein requests and responses (FIG. 3) carrying the same sequence number are exchanged over a plurality of currently inactive links, and each acceptable request/response pair is taken as indicator that the particular link over which it was exchanged is "clean".
Claim 10
Dependent Claim
23 words
Method according to claim 7, wherein transmission of data is switched by the sender randomly to any one of said "clean", inactive links.
References Cited (Backward Citations)
WO1985004300A1
Cited
US4617657A
Cited
US4669113A
Cited
EP0224895A2
Cited
US4862496A
Cited
US4788721A
Cited
US5222061A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1998-07-03 | 1999-01-02 | 1999-07-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2002-07-03 | 2003-01-02 | 2003-07-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2006-07-03 | 2007-01-02 | 2007-07-04 | $7700.00 | Window Closed / Lapsed |