System and method for call admission control

• US 20020097674A1
• Filed: 09/13/2001
• Published: 07/25/2002
• Est. Priority Date: 09/22/2000
• Status: Abandoned Application

• Current Assignee: PhyFlex Networks, Inc. (Ciena Corporation)
• Original Assignee: PhyFlex Networks, Inc. (Ciena Corporation)
• Inventors: Saxena, Prashant, Balabhadrapatruni, Srinivas, Rege, Kiran M., Nanda, Sanjiv, Tandon, Manas, Desai, Gautam, Dorbala, Prasad, Kumar, Ravi S., Loke, Srinivas
• Application Number:
  US09/952,327
• Publication Number:
  US 20020097674A1
• Time in Patent Office: Days
• US Class Current: 370/229
• CPC Class Codes: H04L 12/2801 Broadband local area networks
• CPC Class Codes: H04L 12/2856 Access arrangements, e.g. Internet access asynchronous transfer mode networks H04L12/5601; broadband local area networks H04L12/2801; optical access or distribution networks H04Q11/0067; access to open networks H04L12/5691; digital subscriber line end-user equipment and bit-level processing of data on a PSTN-based network H04M11/00; home network gateways H04L12/2834; wireless access networks H04W
• CPC Class Codes: H04L 12/2859 Point-to-point connection between the data network and the subscribers encapsulation H04L12/4633; virtual LANs H04L12/4641; routing of packets H04L45/00
• CPC Class Codes: H04L 12/2876 Handling of subscriber policies group policies management H04L41/0893
• CPC Class Codes: H04L 12/4641 Virtual LANs, VLANs, e.g. virtual private networks [VPN] LAN interconnection over a bridge based backbone H04L12/462; encapsulation techniques H04L12/4633; routing of packets H04L45/00; packet switches H04L49/00; virtual private networks for security H04L63/0272
• CPC Class Codes: H04L 2012/5605 Fibre
• CPC Class Codes: H04L 2012/5606 Metallic
• CPC Class Codes: H04L 2012/561 Star, e.g. cross-connect, concentrator, subscriber group equipment, remote electronics
• CPC Class Codes: H04L 2012/5651 Priority, marking, classes
• CPC Class Codes: H04L 2012/5679 Arbitration or scheduling
• CPC Class Codes: H04L 41/12 Discovery or management of network topologies
• CPC Class Codes: H04L 41/5022 by giving priorities, e.g. assigning classes of service
• CPC Class Codes: H04L 41/5054 Automatic deployment of services triggered by the service manager, e.g. service implementation by automatic configuration of network components
• CPC Class Codes: H04L 43/091 Measuring contribution of individual network components to actual service level
• CPC Class Codes: H04L 47/10 Flow control; Congestion control
• CPC Class Codes: H04L 47/15 in relation to multipoint traffic arrangements for broadcast or multicast in data networks H04L12/18
• CPC Class Codes: H04L 47/20 Traffic policing
• CPC Class Codes: H04L 47/24 Traffic characterised by specific attributes, e.g. priority or QoS
• CPC Class Codes: H04L 47/2416 Real-time traffic
• CPC Class Codes: H04L 47/2425 for supporting services specification, e.g. SLA
• CPC Class Codes: H04L 47/2441 : relying on flow classification, e.g. using integrated services [IntServ]
• CPC Class Codes: H04L 47/2491 : Mapping quality of service [QoS] requirements between different networks
• CPC Class Codes: H04L 47/32 : by discarding or delaying data units, e.g. packets or frames
• CPC Class Codes: H04L 47/70 : Admission control; Resource allocation
• CPC Class Codes: H04L 47/724 : at intermediate nodes, e.g. resource reservation protocol [RSVP]
• CPC Class Codes: H04L 47/788 : Autonomous allocation of resources
• CPC Class Codes: H04L 47/801 : Real time traffic
• CPC Class Codes: H04L 47/805 : QOS or priority aware
• CPC Class Codes: H04L 47/822 : Collecting or measuring resource availability data
• CPC Class Codes: H04L 47/829 : Topology based
• CPC Class Codes: H04L 61/5007 : Internet protocol [IP] addresses
• CPC Class Codes: H04L 61/5014 : using dynamic host configuration protocol [DHCP] or bootstrap protocol [BOOTP]
• CPC Class Codes: H04N 21/6118 : involving cable transmission, e.g. using a cable modem
• CPC Class Codes: H04N 21/6168 : involving cable transmission, e.g. using a cable modem
• CPC Class Codes: H04N 7/10 : Adaptations for transmission by electrical cable H04N7/12 takes precedence
• CPC Class Codes: H04N 7/17309 : Transmission or handling of upstream communications
• CPC Class Codes: H04Q 3/0045 : involving hybrid, i.e. a mixture of public and private, or multi-vendor systems

Abstract

Hybrid fiber/coax networks employ the existing cable plant used for cable TV and transmit data signals in a frequency bandwidth above that which is used for cable TV. As this cable plant was deployed in a tree and branch topology, data transmissions may be susceptible to noise, variable transmission loss and frequency dispersion, particularly in the upstream direction. Further, due to the tree and branch topology, homes at the far end of the network experience much greater loss than do the homes that are near to the headend/ONU. The present system, which uses point-to-point data links between intelligent network elements located in the feeder/distribution network to provide reliable, secure, bi-directional broadband access. Connections are established by a call admission control (CAC) server which determines utilization, computes required bandwidth and selectively allows additional connections based on available bandwidth. Digital signals are terminated at the intelligent network elements, switched and regenerated for transmission across additional upstream or downstream data links as needed to connect a home to a headend or router. The intelligent network elements can be co-located with or replace the standard network elements to take advantage of existing network configurations. In this manner, the data links are made over relatively short runs of coax cable, which can provide greater bandwidth than the typical end-to-end feeder/distribution connection between a home and the headend or optical network unit.

Claims

1. A method of granting a connection for carrying network traffic in a communication network comprising:

determining critical segments in the communication network traversed by the connection, the connection operable to carry network traffic;

determining an existing load profile for at least one of the critical segments, the existing load profile comprising associated utilization data indicative of existing traffic on the critical segment;

determining, for each of the critical segments, an augmented load profile indicative of the load profile that would result from granting the connection;

granting, if the augmented load profile for each of the critical segments is within a corresponding admissible region, the connection; and

updating, if the connection is granted, the existing load profile with the augmented load profile.

2. The method of claim 1 wherein the admissible region corresponds to quality of service (QOS) classes maintained by the network.

3. The method of claim 1 further comprising mapping at least one critical segment to a network interface unit (NIU), the NIU connected to at least one end user device and operable to transmit data between the end user device and the at least one critical segment.

6. The method of claim 2 wherein the admissible region corresponding to a critical segment is indicative of the upper limits of an aggregate bandwidth utilization over the critical segment due to the different QOS classes.

7. The method of claim 1 wherein the critical segment is a portion of the network which carries traffic at a rate lower than the rate at which the traffic will be carried beyond the critical segment.

8. The method of claim 1 wherein the network traffic is upstream traffic.

9. The method of claim 1 further comprising selectively establishing a connection based on the resource utilization data.

10. The method of claim 9 further comprising storing connection data indicative of the connection when the selectively establishing results in a granted connection.

11. The method of claim 10 wherein the connection data further comprises at least one of call agent/provisioning server ID, connection/provisioned service ID, connection state, service type, NIU ID, critical segments list, original traffic descriptor, derived traffic descriptor, packet classifier information, and service specific options.

12. The method of claim 2 wherein the QOS classes further comprise constant bit rate real-time (CBR-RT), variable bit rate real-time (VBR-RT), variable bit rate non-real-time (VBR-nRT), and unspecified bit rate (UBR) classes.

14. The system of claim 13 wherein the admissible region corresponds to quality of service (QOS) classes maintained by the network.

15. The system of claim 13 further comprising a network interface unit (NIU), the NIU connected to at least one end user device and operable to transmit data between the end user device and the at least one critical segment.

16. The system of claim 13 wherein the resource utilization data is a vector with each entry corresponding to the total bandwidth utilization on the critical segment indicative of a priority class with guaranteed QOS.

17. The system of claim 16 wherein the vector is a three tuple.

18. The system of claim 13 wherein the admissible region corresponding to a critical segment is indicative of the upper limits of an aggregate bandwidth utilization over the critical segment due to the QOS classes.

19. The system of claim 13 wherein the critical segment is a portion of the network which carries traffic at a rate lower than the rate at which the traffic will be carried beyond the critical segment.

20. The system of claim 13 wherein the network traffic is upstream traffic.

21. The system of claim 13 wherein the CAC server is further operable to selectively establish a connection based on the resource utilization data.

22. The system of claim 13 wherein the CAC database is further operable to store connection data indicative of the connection when the selectively establishing grants a connection.

23. The system of claim 22 wherein the connection data further comprises at least one of call agent/provisioning server ID, connection/provisioned service ID, connection state, service type, NIU ID, critical segments list, original traffic descriptor, derived traffic descriptor, packet classifier information, and service specific options.

24. The system of claim 13 wherein the QOS classes further comprise constant bit rate real-time (CBR-RT), variable bit rate real-time (VBR-RT), variable bit rate non-real-time (VBR-nRT), and unspecified bit rate (UBR) classes.

4. The method of claim 4 wherein the utilization data is a vector with each entry corresponding to the total bandwidth utilization on the critical segment corresponding to a priority class with guaranteed QOS (Quality of Service).

5. The method of claim 4 wherein the vector is a three tuple.

13. A system for granting connections for carrying network traffic in a communications network comprising:

a plurality of interconnected intelligent network elements operable to transport network traffic;

a topology server operable to provide topology data indicative of critical segments between the interconnected nodes;

a call admission control (CAC) server operable to compute a load profile for the critical segments from the data; and

a CAC database operable to store the load profile, the load profile comprising resource utilization data, the CAC server operable to grant connections over the critical segments if the load profile for the critical segment augmented with the load associated with the connection is within an admissible region, and further operable to update and store the load profile, the updated load profile comprising the resource utilization data indicative of the granted connection.

25. A computer program product including computer program code for granting a connection for carrying network traffic in a communication network comprising:

computer program code for determining critical segments in the communication network traversed by the connection;

computer program code for determining a load profile for at least one of the critical segments, the load profile comprising associated utilization parameters;

computer program code for granting, if the determined load profile for each of the critical segments augmented with the load associated with the connection is within a corresponding admissible region, the connection; and

computer program code for updating, if the connection is granted, the load profile as a result of granting the connection, the updating creating augmented utilization data indicative of the granted connection.

26. A computer data signal having program code for granting a connection for carrying network traffic in a communication network comprising:

program code for determining critical segments in the communication network traversed by the connection;

program code for determining a load profile for at least one of the critical segments, the load profile comprising associated utilization parameters;

program code for granting, if the determined load profile for each of the critical segments augmented with the load associated with the connection is within a corresponding admissible region, the connection; and

program code for updating, if the connection is granted, the load profile as a result of granting the connection, the updating creating augmented utilization data indicative of the granted connection.

27. A system for granting connections for carrying network traffic in a communications network comprising:

means for determining critical segments in the communication network traversed by the connection;

means for determining a load profile for at least one of the critical segments, the load profile comprising associated utilization parameters;

means for granting, if the determined load profile for each of the critical segments augmented with the load associated with the connection is within a corresponding admissible region, the connection; and

means for updating, if the connection is granted, the load profile as a result of granting the connection, the updating creating augmented utilization data indicative of the granted connection.