Mobile IP communication scheme using dynamic address allocation protocol

• US 6,934,274 B2
• Filed: 07/01/2002
• Issued: 08/23/2005
• Est. Priority Date: 02/20/1998
• Status: Expired due to Fees

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Ishiyama, Masahiro, Inoue, Atsushi, Goto, Masataka, Fukumoto, Atsushi, Okamoto, Toshio, Tsuda, Yoshiyuki, Kumaki, Yoshinari
• Primary Examiner(s): NGUYEN, HANH N
• Application Number:
  US10/184,930
• Publication Number:
  US 20020167922A1
• Time in Patent Office: 1,149 Days
• Field of Search: 455/432, 455/427, 455/428, 455/430, 455/433, 455/435, 370/338, 370/331, 370/352, 370/354, 370/313, 370/329, 370/392, 370/389, 709/245, 709/224, 709/201, 709/202, 709/203
• US Class Current: 370/338
• CPC Class Codes: H04L 61/5007 Internet protocol [IP] addresses
• CPC Class Codes: H04L 61/5014 using dynamic host configuration protocol [DHCP] or bootstrap protocol [BOOTP]
• CPC Class Codes: H04L 61/5046 Resolving address allocation conflicts; Testing of addresses testing when self-assigning an address H04L61/5092
• CPC Class Codes: H04L 61/5084 Providing for device mobility network addressing or numbering for mobility support in wireless networks H04W8/26; mobile IP H04W80/04
• CPC Class Codes: H04L 69/16 Implementation or adaptation of Internet protocol [IP], of transmission control protocol [TCP] or of user datagram protocol [UDP]
• CPC Class Codes: H04L 69/163 In-band adaptation of TCP data exchange; In-band control procedures
• CPC Class Codes: H04W 60/04 using triggered events
• CPC Class Codes: H04W 8/06 Registration at serving network Location Register, VLR or user mobility server
• CPC Class Codes: H04W 8/26 Network addressing or numbering for mobility support
• CPC Class Codes: H04W 80/04 Network layer protocols, e.g. mobile IP [Internet Protocol]
• CPC Class Codes: H04W 88/182 Network node acting on behalf of an other network entity, e.g. proxy

Abstract

A mobile IP communication scheme in which the mobile computer can be operated using the mobile communication protocol such as Mobile IP even in the case where the home network is operated by the dynamic address allocation protocol such as DHCP is disclosed. The current location registration message to be transmitted by the mobile computer from the visited site to the mobile computer management device contains an information indicating that the dynamic address allocation has been received at the home network and an information capable of identifying the mobile computer, and the mobile computer management device carries out exchanges with the dynamic address management server on behalf of the mobile computer, so that the mobile computer which has received the dynamic address allocation at the home network can be operated at the visited site by using the mobile communication protocol.

Claims

1. A mobile computer device capable of carrying out communications while moving among inter-connected networks which includes a mobile computer management device provided at a home network of the mobile computer device for transferring packets destined to the mobile computer device to a current location of the mobile computer device, the mobile computer device comprising:

a transmission unit configured to transmit a message for requesting not to allocate a dynamic address allocated to the mobile computer device at the home network to another computer for a prescribed period of time, to one of an address management server of the home network and the mobile computer management device; and

a mobile communication unit configred to exchange messages with the mobile computer management device and carry out mobile communications using the dynamic address allocated to the mobile computer device at the home network, after the mobile computer device moved outside the home network,

wherein said request message sent by the mobile computer device has a lease time set to be a time amount x and is periodically at a periodic time amount y, and wherein y is greater than or equal to x.

2. The mobile computer device of claim 1, further comprising:

a dynamic host configuration protocol (DHCP) server,

wherein the mobile computer device transmits the request message to the mobile computer management device for requesting not to allocate a dynamic address allocated to the mobile computer device.

3. The mobile computer device of claim 2, wherein the mobile computer management device periodically sends the request message to the DHCP server at the periodic time amount y until a local registration message for mobile communications is received from the mobile computer device.

4. A mobile computer management method for a communication system having a mobile computer which is capable of carrying out communications while moving among networks, and a mobile computer management device provided at a home network of the mobile computer for transferring packets destined to the mobile computer to a current location of the mobile computer, the mobile computer management method comprising:

transmitting from the mobile computer a message for requesting not to allocate a dynamic address allocated to the mobile computer at the home network to another computer for a prescribed period of time, to one of an address management server of the home network and the mobile computer management device; and

exchanging messages with the mobile computer management device and carrying out mobile communications using the dynamic address allocate to the mobile computer at the home network, at the mobile computer after the mobile computer moved outside the home network,

wherein said request message sent by the mobile computer device has a lease time set to be a time amount x and is periodically sent at a periodic time amount y, and wherein y is greater than or equal to x.

5. The mobile computer management method of claim 4, further comprising:

transmiting the request message to the mobile computer management device for requesting not to allocate a dynamic address allocated to the mobile computer device.

6. The mobile computer management method of claim 5, wherein the mobile computer management device periodically sends the request message to the DHCP server at the periodic time amount y until a local registration message for mobile communications is received from the mobile computer device.

7. A computer program product for causing a computer to function as a mobile computer device capable of carrying out communications while moving among inter-connected networks which includes a mobile computer management device provided at a home network of the mobile computer device for transferring packets destined to the mobile computer device to a current location of the mobile computer device, the computer program product comprising:

a first computer program code for causing the computer to transmit a message for requesting not to allocate a dynamic address allocated to the mobile computer device at the home network to another computer for a prescribed period of time, to one of an address management server of the home network and the mobile computer management device; and

a second computer program code for causing the computer to exchange messages with the mobile computer management device and carry out mobile communications using the dynamic address allocated to the mobile computer device at the home network, after the mobile computer device moved outside the home network,

wherein said request message sent by the mobile computer device has a lease time set to be a time amount x and is periodically sent at a periodic time amount y, and wherein y is greater than or equal to x.

8. The computer program product of claim 7, further comprising:

third computer program code for causing the mobile computer device to transmit the request message to the mobile computer management device for requesting not to allocate a dynamic address allocated to the mobile computer device.

9. The computer program product of claim 8, wherein the mobile computer management device periodically sends the request message to the DHCP server at the periodic time amount y until a local registration message for mobile communications is received from the mobile computer device.