System and method for information retrieval regarding services

• US 7,200,596 B2
• Filed: 09/25/2001
• Issued: 04/03/2007
• Est. Priority Date: 10/20/1998
• Status: Expired due to Fees

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Johnson, Richard, Shah, Dhaval N.
• Primary Examiner(s): LEROUX, ETIENNE PIERRE
• Application Number:
  US09/964,268
• Publication Number:
  US 20020049762A1
• Time in Patent Office: 2,016 Days
• Field of Search: 707/1, 707/3, 707/10, 707/100, 707/2, 707/5, 707/200, 709/226, 709/200, 370/236, 379/112.01
• US Class Current: 1/1
• CPC Class Codes: H04L 45/02 Topology update or discovery
• CPC Class Codes: H04L 45/033 by updating distance vector protocols
• CPC Class Codes: H04L 45/742 Route cache; Operation thereof

Abstract

The present invention relates to a system and method for information retrieval related to a service. According to an embodiment of the present invention, two separate types of packets may be received to indicate information which is required. One type of packet is intended for information which may be directly looked up in a table, such as a routing table, while the other type of packet is intended for information which requires calculating or measuring metrics. Accordingly, if information which may be directly looked up in a routing table is requested along with information regarding metrics which need to be measured or calculated, then the routing table information is sent as soon as the requested information is looked up and the measured metric information is sent later when the requested metric is measured.

Claims

1. A method for selecting a mirrored service comprising:

configuring a distributed director with criteria for service selection;

assigning a weight to each criterion;

assigning a priority to each criterion;

determining that metric information is required by at least one of the criteria;

requesting metric information for each mirrored service for each criterion for which metric information is required;

comparing the requested metric information of at least one of the criteria with the highest priority for each mirrored service;

selecting the service with the fastest metric information with respect to the highest priority criterion;

determining that the metric information of the highest priority criterion is equal for two or more mirrored services and in response comparing the metric information of the criterion with the next highest priority for each mirrored service; and

selecting the service with the fastest metric information with respect to the next highest priority criterion.

2. The method of claim 1 wherein the criteria comprises members from the set consisting of a portion scheme, an administrative cost scheme, a random scheme, a round trip time scheme, an external metrics scheme, an internal metrics scheme, a server metrics scheme, a local preferences scheme, a community attribute scheme, and a BGP attribute scheme.

3. A system for selecting a mirrored service comprising:

a distributed director operable to;

be configured with criteria for service selection;

assign a weight to each criteria;

assign a priority to each criterion;

determine that metric information is required by at least one of the criteria;

request metric information for each mirrored service for each criterion for which metric information is required;

apply a selection algorithm, said algorithm comprising

comparing the requested metric information of at least one of the criteria with the highest priority for each mirrored service;

selecting the service with the fastest metric information with respect to the highest priority criterion;

determining that the metric information of the highest priority criterion is equal for two or more mirrored services and in response comparing the metric information of the criterion with the next highest priority for each mirrored service; and

selecting the service with the fastest metric information with respect to the next highest priority criterion.

4. The system of claim 3 wherein the criteria comprises members from the set consisting of a portion scheme, an administrative cost scheme, a random scheme, a round trip time scheme, an external metrics scheme, an internal metrics scheme, a server metrics scheme, a local preferences scheme, a community attributes scheme, and a BGP attribute scheme.

5. A distributed director comprising:

logic encoded in a computer readable media operable to;

be configured with criteria for service selection;

assign a weight to each criterion;

assign a priority to each criterion;

determine that metric information is required by at least one of the criteria

request metric information for each mirrored service for each criterion for which metric information is required;

apply a selection algorithm said algorithm comprising

comparing the requested metric information of at least one of the criteria with the highest priority for each mirrored service;

selecting the service with the fastest metric information with respect to the highest priority criterion;

determining that the metric information of the highest priority criterion is equal for two or more mirrored services and in response comparing the metric information of the criterion with the next highest priority for each mirrored service; and

selecting the service with the fastest metric information with respect to the next highest priority criterion.

6. The distributed director of claim 5 wherein the criteria comprises members from the set consisting of a portion scheme, an administrative cost scheme, a random scheme, a round trip time scheme, an external metrics scheme, an internal metrics scheme, a server metrics scheme, a local preferences scheme, a community attributes scheme, and a BGP attribute scheme.