Automated and adaptive management of bandwidth capacity in telecommunications networks

• US 6,842,463 B1
• Filed: 07/14/2000
• Issued: 01/11/2005
• Est. Priority Date: 07/14/2000
• Status: Expired due to Fees

• Current Assignee: RPX Clearinghouse LLC (RPX Corporation)
• Original Assignee: Nortel Networks Limited (Nortel Networks Corporation)
• Inventors: Yan, James J., Drwiega, Tadeusz J.
• Primary Examiner(s): Vanderpuye, Kenneth
• Assistant Examiner(s): NGUYEN, VAN KIM T
• Application Number:
  US09/617,232
• Time in Patent Office: 1,642 Days
• Field of Search: 370229-238, 370252-258, 370389-392, 370/395.1, 370396-397, 370418-422, 370400-409, 709/105, 709/220, 709/222, 709/238
• US Class Current: 370/468
• CPC Class Codes: H04L 2212/00 Encapsulation of packets
• CPC Class Codes: H04L 41/0896 Bandwidth or capacity management, i.e. automatically increasing or decreasing capacities flow or congestion control using dynamic resource allocation, e.g. in-call renegotiation, H04L47/76
• CPC Class Codes: H04L 45/04 Interdomain routing, e.g. hierarchical routing
• CPC Class Codes: H04L 45/123 Evaluation of link metrics techniques for monitoring network metrics H04L43/08
• CPC Class Codes: H04L 45/22 Alternate routing
• 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 47/16 in connection oriented networks, e.g. frame relay
• 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 47/745 Reaction in network
• CPC Class Codes: H04L 47/762 triggered by the network
• CPC Class Codes: H04L 47/822 Collecting or measuring resource availability data
• CPC Class Codes: H04L 47/825 Involving tunnels, e.g. MPLS

Abstract

Management of the bandwidth capacity of tunnels through a network may be automated such that the network is adaptive to the stochastic nature of incoming traffic. An edge node in the network includes four main elements. Three of the elements, namely tunnel signaling, admission control and path selection, are derived from known technologies, generalized from their particular technologies and enhanced. With the addition of a fourth element, called capacity management, the four elements cooperate to accommodate the capacity needs of the traffic incoming to the network at the edge node. This accommodation is performed by estimating the traffic demand and dynamically adapting tunnels to the traffic demand.

Claims

1. A method for changing a reserved capacity for a given tunnel, comprising:

receiving an indication of traffic demand for a tunnel through a network;

based on said received indication, determining an estimated total capacity requirement;

comparing said estimated total capacity requirement to said reserved capacity;

where said estimated total capacity requirement exceeds said reserved capacity, requesting an increase of said reserved capacity;

determining whether a current path of said tunnel has sufficient available capacity to accommodate said estimated total capacity requirement, said current path having a source node and a destination node;

where said current path of said tunnel has sufficient available capacity to accommodate said increase, transmitting signaling to nodes along said current path to request said increase of said reserved capacity;

where said current path of said tunnel has insufficient available capacity to accommodate said increase, determining a plurality of paths through said network from said source node to said destination node, where each path of said plurality of paths has an associated available capacity; and

selecting one path of said plurality of paths having sufficient associated available capacity to accommodate said estimated total capacity requirement.

2. The method of claim 1, further comprising:

transmitting signaling to nodes along said selected one path of said plurality of paths

to request said estimated total capacity requirement; and

moving said tunnel to said selected one of said plurality of paths.

8. The method of claim 1 wherein said receiving said indication of traffic demand comprises:

receiving an indication of tunnel capacity in use by serviced requests; and

receiving an indication of tunnel capacity refused admission to the tunnel.

9. The method of claim 1 wherein said requested increase of said reserved capacity comprises a difference between said reserved capacity and said estimated total capacity requirement.

10. The method of claim 1 wherein said requested increase of said reserved capacity comprises a difference between said reserved capacity and a sum of said estimated total capacity requirement and a buffer value.

3. A method for changing a reserved capacity for a given tunnel, comprising,

receiving an indication of traffic demand for a tunnel through a network;

based on said received indication, determining an estimated total capacity requirement;

comparing said estimated total capacity requirement to said reserved capacity;

where said estimated total capacity requirement exceeds said reserved capacity, requesting an increase of said reserved capacity;

determining whether a current path of said tunnel has sufficient available capacity to accommodate said estimated total capacity requirement, said current path having a source node and a destination node;

where said current path of said tunnel has sufficient available capacity to accommodate said increase, transmitting signaling to nodes along said current path to request said increase of said reserved capacity;

where said current path of said tunnel has insufficient available capacity to accommodate said increase, determining a plurality of paths through said network from said source node to said destination node, where each path of said plurality of paths has an associated available capacity;

where said estimated total capacity requirement exceeds said associated available capacity of each of said plurality of paths, determining a limiting link in said current path, where said limiting link has a minimum available capacity among links in said current path; and

communicating with a lower level network to request an increase of available capacity on said limiting link.

4. The method of claim 3 further comprising,

where said request to said lower level network is accepted;

transmitting signaling to nodes along said current path to request said increase of said reserved capacity to said estimated total capacity requirement.

5. The method claim 3 further comprising,

where said lower level network returns an available capacity of said limiting link and where said estimated total capacity requirement exceeds said available capacity of said limiting link,

selecting one path of said plurality of paths having a maximum associated available capacity among said plurality of paths;

where said available capacity of said limiting link exceeds said associated available capacity of said selected one path of said plurality of paths;

transmitting signaling to nodes along said current path to request that said reserved capacity be increased to said available capacity of said limiting link.

6. The method of claim 3 further comprising,

where said lower level network returns an available capacity of said limiting link and where said estimated total capacity requirement exceeds said available capacity of said limiting link,

selecting one path of said plurality of paths having a maximum associated available capacity among said plurality of paths;

where said available capacity associated with said selected one path of said plurality of paths exceeds said available capacity of said limiting link;

transmitting signaling to nodes along said selected one of said plurality of paths to request said estimated total capacity requirement; and

moving said tunnel to said selected one of said plurality of paths.

7. The method of claim 3 further comprising where said request to said lower level network is rejected:

selecting one path of said plurality of paths having a maximum associated available capacity among said plurality of paths;

transmitting signaling to nodes along said selected one of said plurality of paths to request said associated available capacity; and

moving said tunnel to said selected one of said plurality of paths.

11. A system for automated adjustment of a reserved capacity for a tunnel, said tunnel associated with a current path through a network, where along said current path are nodes and said current path has a source node and a destination node, said system comprising:

a tunnel signaler operable to transmit a capacity increase request to said nodes along said current path, said capacity increase request indicating a requested increase of said

reserved capacity;

an admission controller;

a capacity manager operable to;

receive, from said admission controller, an indication of traffic demand for said tunnel;

determine an estimated total capacity requirement based in said received indication;

compare said estimated total capacity requirement to said reserved capacity; and

responsive to determining through said comparing, that said estimated tunnel total capacity requirement exceeds said reserved capacity, instruct said tunnel signaler to transmit said capacity increase request; and

a path selector operable to;

determine a plurality of paths through said network from said source node to said destination node, where each path of said plurality of paths has an associated available capacity; and

select one path of said plurality of paths having sufficient associated available capacity to accommodate said estimated total capacity requirement.