Proxy server selecting server and proxy server

• US 6,973,485 B2
• Filed: 10/30/2002
• Issued: 12/06/2005
• Est. Priority Date: 10/07/1997
• Status: Expired due to Fees

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Saito, Masato, Kamata, Yoshihiro, Ito, Hiromichi, Ebata, Tomoichi
• Primary Examiner(s): Jean, Frantz B.
• Application Number:
  US10/283,108
• Publication Number:
  US 20030061282A1
• Time in Patent Office: 1,133 Days
• Field of Search: 709217-219, 709/225, 709/226, 709/203, 709/229
• US Class Current: 709/219
• CPC Class Codes: H04L 61/4511 using domain name system [DNS]
• CPC Class Codes: H04L 63/0281 Proxies
• CPC Class Codes: H04L 63/029 Firewall traversal, e.g. tunnelling or, creating pinholes
• CPC Class Codes: H04L 63/083 using passwords cryptographic mechanisms or cryptographic arrangements for entity authentication using a predetermined code H04L9/3226
• 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 67/1021 based on client or server locations
• CPC Class Codes: H04L 67/288 Distributed intermediate devices, i.e. intermediate devices for interaction with other intermediate devices on the same level
• CPC Class Codes: H04L 67/563 Data redirection of data network streams
• CPC Class Codes: H04L 67/5651 Reducing the amount or size of exchanged application data
• CPC Class Codes: H04L 67/5681 Pre-fetching or pre-delivering data based on network characteristics
• CPC Class Codes: H04L 69/329 in the application layer [OSI layer 7]
• CPC Class Codes: H04L 9/40 Network security protocols

Abstract

In an internet having a server for providing service, a client for receiving the service, plural proxy servers for standing proxy for an access to the server done by the client, and a proxy server selecting server for noticing an IP (Internet Protocol) corresponding to a domain name of the client in response to an inquiry with the domain name added thereon, the proxy server selecting server receives a request message with the domain name of the server for providing the target service from the client. Then, the proxy server selecting server notifies the client of the IP address of the most approximate server to the client in place of the IP address of the server, based on the physical/logical location information, and if necessary, the periodically obtained load information of the proxy servers. The client recognizes the proxy server of the IP address given thereto as the server for providing the target service and then makes access to the proxy server.

Claims

1. A proxy server for relaying an access from a client to a server, said proxy server coupled to a network including the server for providing a service and the client for receiving the service, said proxy server comprising:

a measuring unit for measuring a number of accesses by the client to a resource on the server;

a resource obtaining unit for obtaining said resource from the server if the number of accesses measured by said measuring unit exceeds a predetermined threshold value;

a resource storing unit for storing said resource obtained by said resource obtaining unit; and

an access destination switching unit for switching an access destination of the client to said resource stored in said resource storing unit.

2. A proxy server for relaying an access from a client to a server, said proxy server coupled to a network including the server for providing a service, other proxy servers and the client for receiving the service, said proxy server comprising:

a resource storing unit for storing a resource of a user;

a resource determining unit for determining if a latest resource is stored in said resource storing unit after receiving a downloading request to download said resource from the client;

a first resource transfer unit for transferring the latest resource stored in said resource storing unit to the client if said resource determining unit determines that the latest resource is stored in said resource storing unit;

a resource obtaining unit for obtaining the latest resource if said resource determining unit determines that the latest resource is not stored in said resource storing unit; and

a second resource transfer unit for storing the latest resource obtained by said resource obtaining unit in said resource storing unit and for transferring the latest resource stored in the resource storing unit to the client.

3. The proxy server as claimed by claim 2, wherein:

said resource storing unit stores said resource if said resource is transferred from the client to said proxy server,

said proxy server further comprises a notifying unit for notifying the server that said latest resource is located in said proxy server if said resource storing unit stores said resource, and

said resource determining unit transmits a request to the server, said request for inquiring a location of the latest resource, said resource determining unit for obtaining a response from said request and determining if the latest resource is stored in said resource storing unit based on said request.

4. A server for providing a service, said server being coupled to a network including clients and proxy servers, one of said clients for receiving the service, one of said proxy servers for standing proxy for a request provided by said one client, said server comprising:

a resource storing unit for storing a resource of a user;

a location storing unit for storing a location of a latest resource;

a location updating unit for updating a stored content of said location storing unit if a notice is received from a proxy server indicating that the latest resource is located at the resource storing unit;

a location identifying unit for identifying a location of the latest resource of inquiry based on the stored content of said location storing unit, if a request for inquiring a location of the latest resource is provided by said one proxy server;

a first location responding unit for transmitting information to said one proxy server indicating that a location identified by said location identifying unit is either said one proxy server or the server;

a resource obtaining unit for obtaining the latest resource if the location identified by said location identifying unit is neither said one proxy server nor said server; and

a second location responding unit for storing the latest resource obtained by said resource obtaining unit in said resource storing unit, for updating the stored content of said location storing unit, and for transmitting a response to said one proxy server indicating that the location of the latest resource is said server.

5. A recording medium storing a program to be executed by a server for providing a service, said server being coupled to a network including clients and proxy servers, one of said clients for receiving the service, one of said proxy servers for standing proxy for a request provided by said one client, said program when executed causes said server to perform the steps of:

storing a resource of a user in a resource storing unit;

storing a location of a latest resource in a location storing unit;

updating, by a location updating unit, a stored content of said location storing unit if a notice is received from a proxy server indicating that the latest resource is located at the resource storing unit;

identifying, by a location identifying unit, a location of the latest resource of inquiry based on the stored content of said location storing unit, if a request for inquiring a location of the latest resource is provided by said one proxy server;

transmitting to said one proxy server, by a first location responding unit, information indicating that a location identified by said location identifying unit is either said one proxy server or the server;

obtaining, by a resource obtaining unit, the latest resource if the location identified by said location identifying unit is neither said one proxy server nor said server; and

storing, by a second location responding unit, the latest resource obtained by said resource obtaining unit in said resource storing unit, updating the stored content of said location storing unit, and transmitting to said one proxy server a response indicating that the location of the latest resource is said server.