Method and software for controlling seamless vertical roaming

• US 20060159048A1
• Filed: 01/03/2006
• Published: 07/20/2006
• Est. Priority Date: 07/02/2003
• Status: Abandoned Application

• Current Assignee: KT Freetel Co., Ltd. (KT Corporation)
• Original Assignee: KT Freetel Co., Ltd. (KT Corporation)
• Inventors: Han, Sang-woo, Jeung, Youn-pil
• Application Number:
  US11/324,790
• Publication Number:
  US 20060159048A1
• Time in Patent Office: Days
• US Class Current: 370/331
• CPC Class Codes: H04L 61/45 Network directories; Name-to-address mapping
• 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: H04W 60/00 Affiliation to network, e.g. registration; Terminating affiliation with the network, e.g. de-registration
• CPC Class Codes: H04W 60/005 Multiple registrations, e.g. multihoming
• CPC Class Codes: H04W 8/12 between location registers or mobility servers
• CPC Class Codes: H04W 80/04 Network layer protocols, e.g. mobile IP [Internet Protocol]
• CPC Class Codes: H04W 88/06 adapted for operation in multiple networks or having at least two operational modes, e.g. multi-mode terminals

Abstract

A method and program for controlling seamless vertical roaming between a wireless local area network and a wireless wide area network in a personal communication unit are disclosed. The method includes assigning an Internet Protocol (IP) address by a Foreign Agent (FA); transmitting a Mobile IP (MIP) request message to the FA; receiving a MIP advertisement message from the FA; transmitting a MIP registration request message to the FA; receiving the first MIP address from the FA; determining whether the personal information device has left a WLAN area (hot spot); if the personal information device has left the WLAN area, terminating an operation of the WLAN device and connecting a Point-to-Point Protocol (PPP) session with a Packet Data Serving Node (PDSN) within the WLAN using dial-up networking of the wireless modem at the same time; and receiving a second MIP address from the PDSN. The program is configured to operate the method in a computer or a processor.

Claims

1. A method of controlling seamless vertical roaming in a personal information device equipped with a wireless modem and a Wireless Local Area Network (WLAN) device, the method comprising:

being assigned an Internet Protocol (IP) address by a Foreign Agent (FA) within an accessible WLAN using a Dynamic Host Configuration Protocol (DHCP) client, wherein the IP address is stored on a filter set on a physical layer and registered on a Domain Name Server (DNS) of the WLAN, which is currently being accessed, by the FA;

transmitting a Mobile IP (MIP) request message to the FA;

receiving a MIP advertisement message from the FA;

transmitting a MIP registration request message to the FA, wherein the FA transmits the MIP registration request message to a Home Agent (HA) and receives a first MIP address from the HA;

receiving the first MIP address from the FA, wherein the first MIP address is stored in the filter and the FA registers the first MIP address in the HA;

determining whether the personal information device has left a WLAN area (hot spot);

if, as a result of the determination, the personal information device has left the WLAN area, terminating an operation of the WLAN device and connecting a Point-to-Point Protocol (PPP) session with a Packet Data Serving Node (PDSN) within the WLAN using dial-up networking of the wireless modem at the same time; and

receiving a second MIP address from the PDSN, wherein the second MIP address is assigned by the HA to correspond to the first MIP address and stored in the filter, and the PDSN registers the second MIP address in the HA.

2. The method in claim 1, wherein the filter is set by a control client program that integrally operates the wireless modem and the WLAN device.

3. The method in claim 2, wherein the filter controls headers of data packets or IP packets, which are transmitted and received between the FA or PDSN and the personal information device, between the physical layer and an upper layer above the physical layer.

4. The method in claim 3, wherein the filter comprises a WLAN filter and a MIP filter set on the physical layer.

5. The method in claim 1, further comprising the step of the FA or PDSN requesting access authentication from an Authentication, Authorization and Accounting (AAA) or home AAA (AAAh) and receiving a response thereto at the time of receiving the MIP registration request message.

6. A method of controlling seamless vertical roaming in a personal information device equipped with a wireless modem and a WLAN device, the method comprising:

establishing a PPP session with a PDSN within a wireless network using dial-up networking;

receiving an HA advertisement message from the PDSN;

transmitting a MIP registration request message to the PDSN, wherein the MIP registration request message is transmitted to the HA through a foreign AAA (AAAf) and an internal AAA (AAAh);

receiving a MIP registration reply message from the PDSN, wherein the MIP registration reply message comprises a first MIP address assigned by the HA, the first MIP address is stored in a filter set on a physical layer, and the PDSN registers the first MIP address in the HA;

determining whether the personal information device exists in a WLAN area (hot spot) in a wireless network access state;

if, as a result of the determination, the personal information device exists in the WLAN area, terminating an operation of the wireless modem and being assigned an available IP address from an FA within the WLAN using a DHCP client of the WLAN device at the same time, wherein the IP address is stored in the filter and is registered in a Domain Name Server (DNS) of the WLAN, which is being currently accessed, by the FA; and

receiving a second MIP address from the FA, wherein the second MIP address is assigned by the HA to correspond to the first MIP address and stored in the filter, and the FA registers the second MIP address in the HA.

7. The method in claim 6, wherein the filter is set by a control client program that integrally operates the wireless modem and the WLAN device.

8. The method in claim 7, wherein the filter controls headers of data packets or IP packets, which are transmitted and received between the FA or PDSN and the personal information device, between the physical layer and an upper layer above the physical layer.

9. The method in claim 8, wherein the filter comprises a WLAN filter and a MIP filter set on the physical layer.

10. The method in claim 6, further comprising the step of the FA or PDSN requesting access authentication from an AAA or an AAAh and receiving a response thereto at the time of receiving the MIP registration request message.

11. A computer readable recording medium having stored thereon a computer executable control client program for integrally operating a wireless modem and a WLAN device to perform automatic seamless roaming between a wireless network and a WLAN, the control client program executing a method comprising:

being assigned an IP address by an FA within an accessible WLAN using a DHCP client, wherein the IP address is stored on a filter set on a physical layer and registered on a DNS of the WLAN, which is currently being accessed, by the FA;

transmitting a MIP request message to the FA;

receiving a MIP advertisement message from the FA;

transmitting a MIP registration request message to the FA, wherein the FA transmits the MIP registration request message to a HA and receives a first MIP address from the HA;

receiving the first MIP address from the FA, wherein the first MIP address is stored in the filter and the FA registers the first MIP address in the HA;

determining whether the personal information device has left a WLAN area (hot spot);

if, as a result of the determination, the personal information device has left the WLAN area, terminating an operation of the WLAN device and connecting a PPP session with a PDSN within the WLAN using dial-up networking of the wireless modem at the same time; and

receiving a second MIP address from the PDSN, wherein the second MIP address is assigned by the HA to correspond to the first MIP address and stored in the filter, and the PDSN registers the second MIP address in the HA.

12. A computer readable recording medium having stored a computer executable control client program for integrally operating a wireless modem and a WLAN device to perform automatic seamless roaming between a wireless network and a WLAN, the control client program executing a method comprising:

establishing a PPP session with a PDSN within a wireless network using dial-up networking;

receiving a HA advertisement message from the PDSN;

transmitting a MIP registration request message to the PDSN, wherein the MIP registration request message is transmitted to the HA through an AAAf and an AAAh;

receiving a MIP registration reply message from the PDSN, wherein the MIP registration reply message comprises a first MIP address assigned by the HA, the first MIP address is stored in a filter set on a physical layer, and the PDSN registers the first MIP address in the HA;

determining whether the personal information device exists in a WLAN area (hot spot) in a wireless network access state;

if, as a result of the determination, the personal information device exists in the WLAN area, terminating an operation of the wireless modem and being assigned an available IP address from an FA within the WLAN using a DHCP client of the WLAN device at the same time, wherein the IP address is stored in the filter and is registered in a DNS of the WLAN, which is being currently accessed, by the FA; and

receiving a second MIP address from the FA, wherein the second MIP address is assigned by the HA to correspond to the first MIP address and stored in the filter, and the FA registers the second MIP address in the HA.