Method and apparatus for determination of optimum path routing

• US 20030182410A1
• Filed: 03/20/2002
• Published: 09/25/2003
• Est. Priority Date: 03/20/2002
• Status: Abandoned Application

• Current Assignee: Conxion Corp. (Accenture PLC)
• Original Assignee: Conxion Corp. (Accenture PLC)
• Inventors: Normile, Thomas, Smith, Stacy W., Balan, Sapna
• Application Number:
  US10/105,677
• Publication Number:
  US 20030182410A1
• Time in Patent Office: Days
• US Class Current: 709/223
• CPC Class Codes: H04L 45/00 Routing or path finding of packets in data switching networks routing or path finding in wireless networks H04W40/00
• CPC Class Codes: H04L 67/1001 for accessing one among a plurality of replicated servers
• CPC Class Codes: H04L 67/10015 Access to distributed or replicated servers, e.g. using brokers
• CPC Class Codes: H04L 67/1008 based on parameters of servers, e.g. available memory or workload monitoring of computer activity G06F11/30
• CPC Class Codes: H04L 67/101 based on network conditions
• CPC Class Codes: H04L 67/1012 based on compliance of requirements or conditions with available server resources
• CPC Class Codes: H04L 67/1029 using data related to the state of servers by a load balancer
• CPC Class Codes: H04L 9/40 Network security protocols

Abstract

The method and apparatus of the present invention provide for selection of the optimum mirror site server for a particular client request preferably using anycast IP addressing. Additionally, network performance data such as data pipe load, server load and server configuration are considered to ensure that each communication transaction is completed using the best performance available at the time of the client request.

Claims

1. A method for providing dynamic determination of an optimum path from a remote client terminal to one of a plurality of mirrored content servers in a network, comprising:

monitoring the network to determine parameters representative of network performance;

receiving a request for content residing in said mirrored content servers from the remote client terminal;

resolving said request to a first returned content server IP address based on a default parameter;

analyzing said first returned address for compliance with a predetermined control logic based on predetermined parameters including said parameters representative of network performance, and hops between said servers and the remote client terminal;

repeating said resolving and analyzing with subsequently returned IP addresses as necessary to comply with said control logic; and

returning to said router a content server IP address complying with said control logic.

2. The method of claim 1, wherein said parameters representative of network performance comprise server load, network pipe load and server status.

3. The method of claim 2, wherein said predetermined parameters further include non-network performance parameters.

4. The method of claim 2, wherein said predetermined control logic comprises selecting one said parameter as the default parameter for identifying the first returned IP address and examining other parameters associated with said first returned IP address for compliance with threshold values.

5. The method of claim 4, wherein said default parameter is hops between the client terminal and a content server.

6. The method of claim 4, wherein said default parameter is server load.

7. The method of claim 4, wherein said default parameter is network pipe load.

8. The method of claim 1, wherein said receiving comprises:

monitoring a port for incoming requests containing IP addresses using a client request handler memory module; and

responding to the presence of an IP address request at the port by calling a best server locator memory module.

9. The method of claim 8, wherein said resolving comprises:

receiving in the best server locator module an anycast address from the client request handler module;

comparing said received anycast address from said client request handler module to a list of mirrored content server sites assigned to said received anycast address;

determining within the best server locator module if addresses stored therein match the anycast address received from a client request handler; and

selecting, upon finding a match, a mirrored content server having the least hops to the remote client terminal.

10. The method of claim 1, wherein said analyzing comprises:

determining within a best server locator module if the IP address for a mirrored content server returned by said best server locator module requires a static IP redirect, and if required, returning a corresponding static redirect IP address to the remote client terminal, otherwise;

performing a server load limit check of said mirrored content server represented by said returned IP address, returning said actual IP address of said mirrored content server to said remote client terminal unless said server load limit check requires selection of an alternate mirrored content server;

selecting said alternate mirrored content server if required by said server load limit check; and

returning the IP address of said alternate mirrored content server to said remote client terminal.

16. The method of claim 1, wherein said comparing comprises:

receiving in a best server locator module an anycast address from a client request handler module; and

comparing said received anycast address from said client request handler module to a list of mirrored content server sites assigned to said received anycast address.

18. The method of claim 1, wherein said analyzing comprises:

determining if said physical IP address for a mirrored content server returned by a best server locator module requires a static IP redirect and, if required, returning a corresponding redirect static IP address to the remote client terminal, otherwise;

performing a server load limit check of said mirrored content server represented by said returned physical IP address, returning said actual IP address of said mirrored content server to said remote client terminal unless said server load limit check requires selection of an alternate mirrored content server; and

selecting said alternate mirrored content server if required by said server load limit check.

19. The method of claim 18, wherein said server load limit check further comprises:

checking the status of the mirrored content server;

determining the data load on said mirrored content server;

determining the data load on the data pipe used by said mirrored content server; and

returning a check OK status unless an error is detected causing the client request handler module to execute an error handling routine.

11. An apparatus for determining a path from a remote client to one of a plurality of mirrored content servers in a network, said apparatus comprising a processor communicating with a memory, wherein said memory comprises modules executable by the processor, including:

a best server locator module reading predetermined parameters including at least parameters indicative of network performance and hops between content servers and client terminal, and returning a server IP address complying with a predetermined control logic based on said predetermined parameters in response to a client content request; and

a client request handler module receiving requests from and forwarding responses to remote client terminals, said client request handler module communicating with the best server locator module.

12. The apparatus according to claim 11, wherein said memory further includes modules receiving network performance parameter updates and modifying data structures read by said best server locator module based on said updates.

13. The apparatus according to claim 12, wherein said modules receiving network performance updates comprise:

a server load detector module detecting server load at said mirrored content sites;

a pipe load detector module detecting pipe load at network routers; and

a server status monitor module detecting operational status of said mirrored content servers.

14. A method for providing dynamic determination of an optimum path from a remote client terminal to one of a plurality of mirrored content servers, comprising:

monitoring the status of a plurality of mirrored content servers sharing a same anycast address;

receiving a request from a remote client terminal, said request containing said anycast address;

comparing said received anycast address to a plurality of stored anycast addresses;

matching said received anycast address to one of the said plurality of stored anycast addresses wherein said matched anycast address is associated to a physical IP address representing a least hops path from said remote client terminal to one of the plurality of said mirrored content sites;

analyzing the current status of said matched mirrored content site; and

returning said physical IP address of said matched mirrored content site to said remote client terminal.

15. The method of claim 14, wherein said receiving comprises:

monitoring port 80 of a receiving device for incoming requests containing anycast addresses using a client request handler module, and;

responding to the presence of an anycast address on said port 80 by calling a best server locator module.

17. The method of claim 14, wherein said matching comprises:

determining within a best server locator module if one of the said plurality of anycast addresses stored therein matches an anycast address received from a client request handler; and

selecting, upon finding a match, a mirrored content server having the least hops to the remote client terminal;

20. The method of claim 14, wherein said monitoring comprises:

checking for occurrence of errors on a continuous basis;

analyzing said occurrence of said errors;

placing said errors into one of a plurality of error categories;

responding to said categorized errors in one of a plurality of ways depending upon the severity of said categorized errors; and

reporting said errors to a log.