Location management server and ethernet-based wireless LAN distribution system having local management server, and embodiment method thereof

• US 7,630,311 B2
• Filed: 04/22/2003
• Issued: 12/08/2009
• Est. Priority Date: 12/02/2002
• Status: Expired due to Fees

• Current Assignee: Electronics and Telecommunications Research Institute
• Original Assignee: Electronics and Telecommunications Research Institute
• Inventors: Park, Ki-Shik, Min, Jae-Hong, Jung, Hee-Young
• Primary Examiner(s): Trost, IV; William
• Assistant Examiner(s): JAIN, RAJ K
• Application Number:
  US10/420,082
• Publication Number:
  US 20040105449A1
• Time in Patent Office: 2,422 Days
• Field of Search: 370/229, 370/235, 370/236, 370/230, 370/230.1, 37039571-39572, 370400-401, 370/352, 370/353, 370/354, 370/355, 370/356, 370/331, 370/389, 370/392, 370/393, 370/399, 455/439, 455/436, 455/525
• US Class Current: 370/235
• CPC Class Codes: H04L 61/00 Network arrangements, protocols or services for addressing or naming
• CPC Class Codes: H04L 61/10 of different types
• CPC Class Codes: H04W 40/02 Communication route or path selection, e.g. power-based or shortest path routing
• CPC Class Codes: H04W 8/02 Processing of mobility data, e.g. registration information at HLR [Home Location Register] or VLR [Visitor Location Register]; Transfer of mobility data, e.g. between HLR, VLR or external networks
• CPC Class Codes: H04W 80/00 Wireless network protocols or protocol adaptations to wireless operation
• CPC Class Codes: H04W 84/12 WLAN [Wireless Local Area Networks]
• CPC Class Codes: H04W 88/08 Access point devices
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

A wireless LAN distribution system, forwarding data received from a correspondent node to a station connected to an access point, includes: a location management server (LMS) for storing and managing a mapping table as an information table storing IP addresses of stations and physical access control addresses of the access points having the stations located therein, and causing the access points to perform an IP address check for the stations located in their area; an edge router for forwarding the data to the LMS using the physical access control address of the mapping table; and an access point for checking the physical access control address of the access point and the IP address of the destination station, and forwarding the data from the correspondent node.

Claims

1. A wireless LAN (Local Access Network) distribution system, which forwards data received from a correspondent node to a destination station among a plurality of stations respectively connected to a plurality of access points, the wireless LAN distribution system comprising:

a location management server for storing and managing a mapping table as an information table storing IP (Internet Protocol) addresses of the plurality of stations and physical access control addresses of the plurality of access points having the stations located therein, the location management server to identify an access point connected to the destination station to cause only the identified access point, from the plurality of access points, to perform an IP address check of the stations located in the area of the identified access point; and

an edge router for, upon receiving the data from the correspondent node via a communication network, forwarding the received data to the location management server,

wherein the location management server identifies the access point connected to the destination station, among the plurality of access points, by checking the IP address of the destination station in the information table,

forwards the received data to the identified access point by using the IP address of the destination station and the physical access address of the identified access point, such that the identified access point forwards the received data to the destination station by using the IP address of the destination station;

generates an acknowledgment (Ack) message in response to receiving association information of the identified access point subsequent to updating the information table with the association information regarding a station within the area of the identified access point, and sends the generated Ack message to the identified access point; and

the location management server including a MAC (Media Access Control) frame generator for generating a MAC frame destined for the identified access point having the destination station located therein.

2. The wireless LAN distribution system as claimed in claim 1, wherein upon receiving an association-related message from the destination station, each of the plurality of access points associates the destination station in its area according to a received association message, and sends information on the associated destination station to the location management server.

3. The wireless LAN distribution system as claimed in claim 2, wherein the received association message includes the IP address of the destination station.

4. The wireless LAN distribution system as claimed in claim 1, wherein the location management server comprises:

a mapping table manager for, upon receiving an association message from the access point, analyzing the IP address of the destination station and the MAC address of an access point having the destination station located therein from the received association message, and managing analyzed information using the mapping table as an information table; and

an IP address checker for checking the IP address of the destination station using the data forwarded from the edge router,

the MAC (Media Access Control) frame generator for, upon receiving information from the IP address checker and the mapping table manager, generating the MAC frame destined for the access point having the destination station located therein according to the received information.

5. The wireless LAN distribution system as claimed in claim 4, wherein the location management server checks the MAC address of the access point having the destination station positioned therein using an ARP (Address Resolution Protocol) stack as an address mapping protocol.

6. The wireless LAN distribution system as claimed in claim 4, wherein the MAC frame generator generates the MAC frame using a packet related to the IP address of the destination station received from the IP address checker, and the MAC address of the access point input from the mapping table under the control of the mapping table manager.

7. The wireless LAN distribution system as claimed in claim 4, wherein the received association message includes information on the destination stations associated with the access point, the MAC address of the access point, and information on the IP address of the associated destination stations.

8. The wireless LAN distribution system as claimed in claim 1, wherein the system conforms to the IEEE 802.3 standard in forwarding data received from the correspondent node to the destination station connected to the access point.

9. A location management server, which is for a wireless LAN distribution system for forwarding data received from an edge router of a correspondent node to a destination station among a plurality of stations respectively connected to a plurality of access points, the location management server comprising:

a mapping table manager for, upon receiving an association message from an access point, analyzing an IP address of the destination station and a MEDIA access control (MAC) address of the access point having the station located therein from a received association message, managing analyzed information through a mapping table as an information table, and generating an acknowledgment (Ack) message in response to the received association message, and sending the generated Ack message to the access point;

an IP address checker for checking the IP address of the destination station using the data forwarded from the outer router of the correspondent node to search the MAC address to identify an access point connected to the destination station among the plurality of access points; and

a MAC frame generator for, upon receiving information from the IP address checker and the mapping table manager, generating a MAC frame destined for the identified access point having the destination station located therein by using the IP address of the destination station and the searched MAC address, and outputting the MAC frame to cause only the identified access point, from the plurality of access points, to perform an IP address check of the stations located in the area of the identified access point.

10. A method for a wireless LAN distribution system, which is for forwarding data received from an edge router of a correspondent node to a station connected to an access point, the method comprising:

(a) upon receiving an association-related message from the station, the access point associating the station in its area according to a received association message;

(b) checking an IP address of the station and a media access control (MAC) address of an access point having the station located therein from the association message including information on the associated station, then managing a mapping table being an information table based on the checked addresses, and sending an acknowledgement signal for the received association message to the access point;

(c) upon receiving data destined for a specific station from the edge router of the correspondent node, checking the IP address of the received data using the mapping table to search the MAC address of an access point identified having the specific station located therein, and to cause only the identified access point, from a plurality of access points, to perform an IP address check of the stations located in the area of the identified access point by checking the IP address of the destination station in the only access point; and

(d) generating a MAC frame based on only the IP address and the searched MAC address, and forwarding the generated physical access control frame to the destination station via only the access point using a computer.

11. The method as claimed in claim 10, wherein (a) comprises:

receiving an association request message from the station, when the station enters a specific access point;

receiving a reassociation request message from the station, when the station moves to another access point; and

receiving a disassociation request message from the station, when the station intends to cancel the existing association.

12. The method as claimed in claim 10, wherein (c) comprises:

searching for the access point having the destination station located therein, the destination station being to receive the data from the correspondent node; and

checking the MAC address of the searched access point.

13. The method as claimed in claim 12, wherein (c) comprises:

checking the MAC address of the access point having the destination station located therein using an ARP stack being an address mapping protocol.

14. The method as claimed in claim 10, wherein (d) comprises:

checking the IP address of the generated MAC frame;

mapping the checked address with the MAC address of the destination station; and

forwarding the data received from the correspondent node to the destination station according to the mapped MAC address.