Connectionless communications network

• US 6,442,147 B1
• Filed: 08/26/1999
• Issued: 08/27/2002
• Est. Priority Date: 04/18/1997
• Status: Expired due to Fees

• Current Assignee: Nortel Networks Limited (Nortel Networks Corporation)
• Original Assignee: Nortel Networks Limited (Nortel Networks Corporation)
• Inventors: Brueckheimer, Simon Daniel, Mauger, Roy Harold
• Primary Examiner(s): Olms, Douglas
• Assistant Examiner(s): VANDERPUYE, KENNETH N
• Application Number:
  US09/380,174
• Time in Patent Office: 1,097 Days
• Field of Search: 370/254, 370/255, 370/474, 370/439, 370/316, 370/476, 370/395.43, 370/395.21, 455/428, 455/422, 455/427, 455/431
• US Class Current: 370/321
• CPC Class Codes: H04B 7/18578 Satellite systems for providing broadband data service to individual earth stations for selecting H04W; provisions for broadband connection, H04Q11/0478
• CPC Class Codes: H04B 7/18584 Arrangements for data networking, i.e. for data packet routing, for congestion control data switching networks H04L12/00
• CPC Class Codes: H04B 7/18589 Arrangements for controlling an end to end session, i.e. for initialising, synchronising or terminating an end to end link
• CPC Class Codes: H04L 2012/5608 Satellite
• CPC Class Codes: H04L 2012/5619 Network Node Interface, e.g. tandem connections, transit switching
• CPC Class Codes: H04L 2012/5623 Network design, dimensioning, topology or optimisation
• CPC Class Codes: H04L 2012/563 Signalling, e.g. protocols, reference model
• CPC Class Codes: H04L 2012/5632 Bandwidth allocation
• CPC Class Codes: H04L 2012/5634 In-call negotiation
• CPC Class Codes: H04L 2012/5638 Services, e.g. multimedia, GOS, QOS
• CPC Class Codes: H04L 2012/5645 Connectionless
• CPC Class Codes: H04L 2012/5651 Priority, marking, classes
• CPC Class Codes: H04L 2012/5656 using the AAL2
• CPC Class Codes: H04L 2012/5672 Multiplexing, e.g. coding, scrambling
• CPC Class Codes: H04L 2012/5675 Timeslot assignment, e.g. TDMA
• CPC Class Codes: H04L 47/10 Flow control; Congestion control
• CPC Class Codes: H04Q 11/0478 Provisions for broadband connections

Abstract

A non-geostationary satellite network incorporates a plurality of satellite nodes and ground stations in communication with the nodes. Routing and control are established from a virtual model of the network. Within the virtual model, a capacity of space segment band width for different traffic QoS classes can be determined. The relationship between the virtual model and the real network is used to transfer the capacity determination to the real network.

Claims

1. A method of determining routing information for calls of different quality of service (QoS) classes, each class having a respective bandwidth requirement, between pairs of end points in a telecommunications packet network having a constantly changing topology and comprising a plurality of non-geostationary satellite nodes being interconnected by inter-satellite communications links established between temporarily adjacent satellites, and ground stations each in communication with the respective satellite node currently nearest to that ground station, the method comprising:

providing a static virtual model of the network, said model comprising an array of fixed virtual nodes wherein each virtual node corresponds to a respective satellite node and wherein direct links are established between adjacent virtual nodes and virtual connections are established between non-adjacent virtual nodes whereby to reduce the topological complexity of the network, periodically determining the relationship between the virtual model and the current satellite network topology so as to update said virtual model with that current topology, and determining within said virtual model routes for said calls and a capacity of space segment bandwidth for the different traffic QoS classes, and transferring the routes and capacity determinations from the modelled virtual network to the real network so as to route the calls through the real network.

2. A method as claimed in claim 1, wherein ground-based traffic employs a TDMA format, and wherein TDMA time slots comprise the units of switching between said satellite nodes.

3. A method as claimed in claim 2, wherein connectionless routing within the satellite network is determined from routing labels.

4. A method as claimed in claim 3, wherein each real satellite network node advertises to adjacent real satellite nodes the identity of the modelled virtual node corresponding to that real node.

5. A method as claimed in claim 4, wherein end to end bandwidth is determined for different traffic QoS classes.

6. A method as claimed in claim 5, wherein call admission to the network is controlled so as to maintain quality of service for each said traffic QoS class.