Communication method

• US 7,292,565 B2
• Filed: 08/06/2003
• Issued: 11/06/2007
• Est. Priority Date: 08/07/2002
• Status: Expired due to Fees

• Current Assignee: Fujitsu Limited
• Original Assignee: Fujitsu Limited
• Inventors: Ono, Hideaki, Oka, Kazuyuki
• Primary Examiner(s): Trinh; Sonny
• Application Number:
  US10/635,209
• Publication Number:
  US 20040072564A1
• Time in Patent Office: 1,553 Days
• Field of Search: 370/313, 370/349, 370/331, 370/338, 370/351, 370/400, 370/328, 370/395.32, 370/352, 370/392, 709/245, 709/249, 455/445, 455/432.1, 455/517, 455/525, 455/452.1
• US Class Current: 370/351
• CPC Class Codes: H04L 9/40 Network security protocols
• CPC Class Codes: H04W 8/082 for traffic bypassing of mobility servers, e.g. location registers, home PLMNs or home agents
• CPC Class Codes: H04W 8/14 between corresponding nodes
• CPC Class Codes: H04W 80/04 Network layer protocols, e.g. mobile IP [Internet Protocol]

Abstract

A communication method is capable of preventing an occurrence a change of a route for an underway communication between a mobile node and a correspondent node in a communication network and restraining an unnecessary packet from being forwarded to the correspondent node from the mobile node. The communication method is executed among the mobile node having a home address assigned in a first network and a temporary address assigned in a second network, an agent device surrogating a communication using the home address in the first network and a correspondent terminal communicating with the mobile node through the agent device. When the mobile node moves to the second network, the mobile node transmits information containing the temporary address to the correspondent node, and the correspondent node receives the information containing the temporary address and transmits the information to the temporary address of the mobile node.

Claims

1. A communication method executed among a mobile terminal having a home address assigned in a first network and a temporary address assigned in a second network, an agent device surrogating a communication using the home address in the first network and a correspondent terminal communicating with said mobile terminal through said agent device, said communication method comprising:

making said mobile terminal transmit, when said mobile terminal moves to the second network, information containing the temporary address to said correspondent terminal;

making said correspondent terminal receive the information containing the temporary address of said mobile terminal; and

making said correspondent terminal transmit, to said mobile terminal, the information addressed to the temporary address of said mobile terminal,

wherein a communication route without through said agent device is established in advance of starting the communication between said mobile terminal and said correspondent terminal.

2. A communication method according to claim 1, further comprising confirming before starting the communication between said mobile terminal and said correspondent terminal whether a request for security is met or not.

3. A communication method according to claim 1, further comprising:

detecting that there is no communication between said mobile terminal and said correspondent terminal for a predetermined period; and

transmitting, when detecting that there is no communication between said mobile terminal and said correspondent terminal, a piece of information for canceling the communication route.

4. A communication method according to claim 1, further comprising:

detecting that there is no communication between said mobile terminal and said correspondent terminal for the predetermined period; and

stopping, when detecting that there is no communication between said mobile terminal and said correspondent terminal, a transmission of a piece of information for keeping the communication route.

5. A communication method according to claim 1, further comprising:

storing information showing that the communication route without through said agent device is once established between said mobile terminal and said correspondent terminal; and

re-establishing the communication route without through said agent device on the basis of the information stored with respect to the communication route.

6. A communication method according to claim 1, further comprising making said correspondent terminal register information about a location of said mobile terminal on the basis of a piggy backing system before starting the communication between said mobile terminal and said correspondent terminal.

7. A communication method executed among a mobile terminal having a home address assigned in a first network and a first temporary address and a second temporary address assigned in a second network, a first agent device surrogating a communication using the home address in the first network, a second agent device surrogating a communication using the first temporary address, and a correspondent terminal communicating with said mobile terminal through said first agent device and said second agent device, said communication method comprising:

making said mobile terminal transmit, when said mobile terminal moves to the second network, information containing the temporary address to said correspondent terminal;

making said correspondent terminal receive the information containing the temporary address of said mobile terminal;

making said correspondent terminal transmit, to said mobile terminal, the information addressed to the temporary address of said mobile terminal; and

making said second agent device transmit, to said mobile terminal, information addressed to the second temporary address,

wherein a communication route without through said first agent device is established in advance of starting the communication between said mobile terminal and said correspondent terminal.

8. A communication method according to claim 7, further comprising confirming before starting the communication between said mobile terminal and said correspondent terminal through said second agent device whether a request for security is met or not.

9. A communication method according to claim 7, further comprising:

detecting that there is no communication between said mobile terminal and said correspondent terminal for a predetermined period; and

transmitting, when detecting that there is no communication between said mobile terminal and said correspondent terminal, a piece of information for canceling the communication route.

10. A communication method according to claim 7, further comprising:

detecting that there is no communication between said mobile terminal and said correspondent terminal for the predetermined period; and

stopping, when detecting that there is no communication between said mobile terminal and said correspondent terminal, a transmission of a piece of information for keeping the communication route.

11. A communication method according to claim 7, further comprising:

storing information showing that the communication route without through said first agent device is once established between said mobile terminal and said correspondent terminal; and

re-establishing the communication route without through said first agent device on the basis of the information stored with respect to the communication route.

12. A communication method according to claim 7, further comprising making said correspondent terminal register information about a location of said mobile terminal on the basis of a piggy backing system before starting the communication between said mobile terminal and said correspondent terminal.

13. A terminal device utilized among a mobile terminal having a home address assigned in a first network and a temporary address assigned in a second network, an agent device surrogating a communication using the home address in the first network and a correspondent terminal communicating with said mobile terminal through said agent device, said terminal device comprising:

a transmitting module transmitting, when said mobile terminal moves to the second network, location information containing the temporary address to said correspondent terminal; and

a receiving module receiving information transmitted by said correspondent terminal;

wherein a communication route without through said agent device is established in advance of starting the communication between said mobile terminal and said correspondent terminal.

14. A terminal device according to claim 13, further comprising a security judging module confirming before starting the communication between said mobile terminal and said correspondent terminal whether a request for security is met or not.

15. A terminal device according to claim 13, further comprising:

a communication monitoring module monitoring a communication state between said mobile terminal and said correspondent terminal; and

a route canceling module transmitting, when detecting that there is no communication between said mobile terminal and said correspondent terminal for a predetermined period, apiece of information for canceling the communication route.

16. A terminal device according to claim 13, further comprising:

a communication monitoring module detecting that there is no communication between said mobile terminal and said correspondent terminal for the predetermined period; and

a stopping module stopping, when detecting that there is no communication between said mobile terminal and said correspondent terminal, a transmission of apiece of information for keeping the communication route.

17. A terminal device according to claim 13, further comprising:

a storing module storing information showing that the communication route without through said agent device is once established between said mobile terminal and said correspondent terminal; and

a communication route re-establishing module re-establishing the communication route without through said agent device on the basis of the information stored with respect to the communication route.

18. A terminal device utilized among a mobile terminal having a home address assigned in a first network and a first temporary address and a second temporary address assigned in a second network, a first agent device surrogating a communication using the home address in the first network, a second agent device surrogating a communication using the first temporary address, and a correspondent terminal communicating with said mobile terminal through said first agent device and said second agent device, said terminal device comprising:

a transmitting module transmitting, when said mobile terminal moves to the second network, information containing the first temporary address to said correspondent terminal;

a receiving module receiving information addressed to the second temporary address that is transmitted by said second agent device; and

a communication route establishing module establishing a communication route without through said first agent device in advance of starting the communication between said mobile terminal and said correspondent terminal.