US5917823A
Expired / Lapsed
US
⏱️ 0.0 years remaining
X.25 access to frame relay network
Assignee: Nokia Canada Inc
•
Filing: 1995-06-07
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Granted: 1999-06-29
•
Expires: 2015-06-07
Abstract
Abstract A packet switching network supporting X-series protocol access employs PVC (Permanent virtual connection) trunks as the backbone trunks for the network.
Inventors
- 👤 Rex Benning
- 👤 Keith Allan
- 👤 Jim Hurd
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 21:56
CPC Classifications
H; H04; H04L; H04L12/00; H04L12/66
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
111 words
A packet switching network supporting X-series protocol access comprising: a plurality of X-series packet engines, each including a routing controller for X-series packets;, and a plurality of discrete trunks interconnecting said X-series packet engines for transporting packets between said packet engines under the control of said routing controller, said trunks serving as the backbone for the network and being in the form of permanent virtual connections established between pairs of said packet engines, said PVCs terminating at said packet engines of each pair; and said routing controllers monitoring the state of said PVCs and routing said X-series packets over said PVCs to establish communication between terminal devices connected to the network.
Claim 2
Dependent Claim
111 words
A packet switching network supporting X-series protocol access comprising: a plurality of X-series packet engines, each including a routing controller for X-series packets;, and a plurality of discrete trunks interconnecting said X-series packet engines for transporting packets between said packet engines under the control of said routing controller, said trunks serving as the backbone for the network and being in the form of permanent virtual connections established between pairs of said packet engines, said PVCs terminating at said packet engines of each pair; and said routing controllers monitoring the state of said PVCs and routing said X-series packets over said PVCs to establish communication between terminal devices connected to the network.
Claim 3
Dependent Claim
41 words
A packet switching network as claimed in claim 1, wherein said PVCs are integrated into a routing system that monitors the states of the PVCs and uses an Open-Shortest-Path-First-like procedure to calculate paths over the PVCs between the X-series packet engines.
Claim 4
Dependent Claim
33 words
A packet switching network as claimed in claim 1, wherein said routing controllers maintain connectivity between said packet engines over said PVCs in the event of failures, errors and congestion in the network.
Claim 5
Dependent Claim
42 words
A packet switching network as claimed in claim 3, wherein means are provided for encapsulating outgoing LAPB (Link Access Protocol Balanced) frames containing X.25 packets into frame relay frames and attaching a DLCI identifier for transmission over the identified permanent virtual connection.
Claim 6
Dependent Claim
16 words
A packet switching network as claimed in claim 1, wherein said PVCs are frame relay PVCs.
Claim 7
Dependent Claim
33 words
A packet switching network as claimed in claim 5, wherein frame relay explicit congestion notification (ECN) bits are used by the packet engines to provide flow control in the individual permanent virtual connections.
Claim 8
Independent Claim
104 words
A method of transferring X.25 packets between packet engines, each including routing software for the X.25 packets, comprising the steps of establishing permanent virtual connections between pairs of said packet engines using frame relay protocol, selecting permanent virtual connections with said routing software to route packets between said packet engines, encapsulating the X.25 packets into frame relay frames and attaching a DLCI (Data Link Connection Identifier) identifier, transmitting the encapsulated frames between the packet engines over said permanent virtual connections under the control of said routing software, and stripping off the frame relay header from the received encapsulated frames to recover the X.25 packets.
Claim 9
Independent Claim
104 words
A method of transferring X.25 packets between packet engines, each including routing software for the X.25 packets, comprising the steps of establishing permanent virtual connections between pairs of said packet engines using frame relay protocol, selecting permanent virtual connections with said routing software to route packets between said packet engines, encapsulating the X.25 packets into frame relay frames and attaching a DLCI (Data Link Connection Identifier) identifier, transmitting the encapsulated frames between the packet engines over said permanent virtual connections under the control of said routing software, and stripping off the frame relay header from the received encapsulated frames to recover the X.25 packets.
References Cited (Backward Citations)
US5251207A
Cited
US5734654A
Cited
US5600798A
Cited
US5533017A
Cited
US5521909A
Cited
US5535199A
Cited
US5490140A
Cited
US5490141A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2002-06-28 | 2002-12-28 | 2003-06-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2006-06-28 | 2006-12-28 | 2007-06-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2010-06-28 | 2010-12-28 | 2011-06-29 | $7700.00 | Window Closed / Lapsed |