Method and apparatus for distributing requests among a plurality of resources

• US 8,458,259 B2
• Filed: 12/23/2011
• Issued: 06/04/2013
• Est. Priority Date: 03/13/1998
• Status: Expired due to Fees

• Current Assignee: Massachusetts Institute of Technology
• Original Assignee: Massachusetts Institute of Technology
• Inventors: Karger, David, Lehman, Eric, Leighton, F. Thomson, Levine, Matthew, Lewin, Daniel, Panagrahy, Rina
• Primary Examiner(s): WINDER, PATRICE L
• Application Number:
  US13/336,745
• Publication Number:
  US 20120124214A1
• Time in Patent Office: 529 Days
• Field of Search: 709/205, 709/238
• US Class Current: 709/205
• CPC Class Codes: G06F 9/5027 the resource being a machine, e.g. CPUs, Servers, Terminals
• CPC Class Codes: H04L 67/10 in which an application is distributed across nodes in the network software deployment G06F8/60; multiprogramming arrangements G06F9/46
• 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 67/1019 Random or heuristic server selection
• CPC Class Codes: H04L 67/1021 based on client or server locations
• CPC Class Codes: H04L 67/1023 based on a hash applied to IP addresses or costs
• CPC Class Codes: H04L 67/568 Storing data temporarily at an intermediate stage, e.g. caching
• CPC Class Codes: H04L 69/329 in the application layer [OSI layer 7]
• CPC Class Codes: H04L 9/40 Network security protocols

Abstract

The invention relates to an apparatus for responding to data requests made by a client. The apparatus includes an input receiving a first data request that includes a sequence of nodes corresponding to a sequence of servers. The apparatus also includes decision logic determining whether the data specified in the data request is available on a selected server, and if the data is not available determining a next node from the sequence of nodes. The apparatus also includes a mapper mapping a server to the next node, and an output requesting the data by transmitting a second data request to the server mapped to the next node.

Claims

1. An apparatus for responding to data requests made by a client, the apparatus comprising:

an input for receiving a first data request comprising a sequence of virtual server nodes that is present in a virtual network of servers, the sequence of virtual server nodes corresponding to a sequence of actual servers;

a processor that executes computer readable instructions; and

computer memory that stores computer readable instructions that, when executed by the processor, cause;

decision logic to determine whether data specified in the first data request is available on a selected actual server, and if the data is not available to determine a next virtual server node from the sequence of virtual server nodes;

a mapper to map an actual server to the next virtual server node; and

an output to request the data by transmitting a second data request to the actual server mapped to the next virtual server node.

2. The apparatus of claim 1, wherein the mapper calculates a hash function in mapping the actual server to the next virtual server node.

3. The apparatus of claim 1, wherein the first data request is substantially similar to the second data request.

4. The apparatus of claim 1, wherein the second data request comprises a sequence of virtual server nodes.

5. The apparatus of claim 1, wherein the selected actual server is a cache server.

6. The apparatus of claim 5 further comprising a request counter that is incremented each time that the data in the first data request is requested.

7. The apparatus of claim 6, wherein the apparatus further caches the data requested by the first data request in the cache server when a count in the request counter exceeds a threshold.

8. The apparatus of claim 1, wherein the input receives the first data request over a computer network.

9. The apparatus of claim 1, wherein the apparatus is a computer and the input receives the first data request from a process that is on the same computer as the input.