Communication network recoverable from link failure using prioritized recovery classes
First Claim
1. A communication network comprising:
- a plurality of network nodes interconnected by communication links, said links accommodating virtual paths that extend between a plurality of user terminals, said virtual paths being respectively identified by priority classes which guarantee a different amount of bandwidth;
a link-path table for mapping said links to said accommodated virtual paths and to bandwidths remaining in the respective links; and
a controller responsive to a fault-indicating message identifying a failed virtual path received from at least one network node for making a search through the link-path table for an alternate virtual path and a remaining bandwidth of each link that comprises the alternate virtual path, determining whether or not the bandwidth guaranteed by the priority class of the failed virtual path can be allocated to the alternate virtual path from the remaining bandwidth in accordance with the priority class of the failed virtual path relative to the priority class of an existing virtual path sharing said each link with said alternate virtual path, and establishing the alternate virtual path if it is determined that the guaranteed bandwidth can be allocated.
1 Assignment
0 Petitions
Accused Products
Abstract
In a self-healing network, virtual paths between user terminals are classified according to different fault recovery priority levels and communication links are mapped to virtual paths accommodated by the links and to bandwidths remaining in the respective links. Each priority level guarantees a fault recovery with a different amount of network resource. In response to a fault-indicating message identifying a failed virtual path, a search is made through the link-path table for an alternate virtual path and a remaining bandwidth of each link that comprises the alternate virtual path in descending order of the priority classes. In accordance with the priority class of the failed virtual path relative to the priority class of an existing virtual path that shares the same link with the alternate virtual path, a decision is made on whether or not the bandwidth guaranteed by the priority class of the failed virtual path can be allocated to the alternate virtual path from the remaining bandwidth. If the decision is affirmative, the alternate virtual path is established.
307 Citations
20 Claims
-
1. A communication network comprising:
-
a plurality of network nodes interconnected by communication links, said links accommodating virtual paths that extend between a plurality of user terminals, said virtual paths being respectively identified by priority classes which guarantee a different amount of bandwidth; a link-path table for mapping said links to said accommodated virtual paths and to bandwidths remaining in the respective links; and a controller responsive to a fault-indicating message identifying a failed virtual path received from at least one network node for making a search through the link-path table for an alternate virtual path and a remaining bandwidth of each link that comprises the alternate virtual path, determining whether or not the bandwidth guaranteed by the priority class of the failed virtual path can be allocated to the alternate virtual path from the remaining bandwidth in accordance with the priority class of the failed virtual path relative to the priority class of an existing virtual path sharing said each link with said alternate virtual path, and establishing the alternate virtual path if it is determined that the guaranteed bandwidth can be allocated. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12)
-
-
13. A fault recovery method for a communication network comprising a plurality of network nodes interconnected by communication links, said links accommodating virtual paths that extend between a plurality of user terminals, the method comprising the steps of:
-
a) assigning priority classes to said virtual paths to guarantee a different amount of bandwidth; b) mapping, in a memory, said links to said accommodated virtual paths and to bandwidths remaining in the respective links; c) making a search, in response to a fault-indicating message identifying a failed virtual path, through the memory and detecting an alternate virtual path and a remaining bandwidth of each of said links that comprises the alternate virtual path; d) determining whether or not the bandwidth guaranteed by the priority class of the failed virtual path can be allocated to the alternate virtual path from the remaining bandwidth in accordance with the priority class of the failed virtual path relative to the priority class of an existing virtual path sharing said each link with said alternate virtual path; and e) establishing the alternate virtual path if it is determined that the guaranteed bandwidth can be allocated. - View Dependent Claims (14, 15, 16, 17, 18)
-
-
19. A fault recovery method for a communication network comprising a plurality of network nodes interconnected by communication links, said links accommodating virtual paths that extend between a plurality of user terminals, the method comprising the steps of:
-
a) assigning priority classes to said virtual paths to guarantee a different amount of bandwidth; b) mapping, in a memory, said links to said accommodated virtual paths and to bandwidths remaining in the respective links; c) making a search, in response to a fault-indicating message identifying a failed virtual path, through the memory and detecting a plurality of alternate virtual paths and a remaining bandwidth of each one of a plurality of said links that comprises each of the alternate virtual paths; d) selecting one of said alternate virtual paths; e) selecting one of said links; f) determining whether or not the bandwidth guaranteed by the priority class of the failed virtual path can be allocated to the selected alternate virtual path from the remaining bandwidth of said selected link in accordance with the priority class of the failed virtual path relative to the priority class of an existing virtual path sharing said selected link with said selected alternate virtual path; g) repeating the steps (e) and (f) for all links of the selected alternate virtual path; and h) establishing the selected alternate virtual path if it is determined that the guaranteed bandwidth can be allocated for all links of the selected alternate virtual path, and repeating the steps (d) to (f) if it is determined that the guaranteed bandwidth cannot be allocated for at least one of said links of the selected alternate virtual path. - View Dependent Claims (20)
-
Specification