Patent Application
20090290564
The present invention relates to an apparatus for and method of supporting network-based mobility for a dual stack terminal, and more particularly, to a mobility anchor point (MAP) apparatus for binding and transmitting data to a dual stack terminal which has moved to an Internet Protocol version 4 (IPv4) network or an Internet Protocol version 6 (IPv6) network.
If Internet Protocol version 6 (IPv6), which is a next-generation Internet protocol, begins to be applied to networks, a dual stack terminal supporting both the IPv4 and IPv6 will be introduced. Dual stack technology is a technology for processing both the IPv4 and IPv6 protocols at the same time in one system (a host or a router). A system supporting dual stack technology is physically one system but operates as if two systems supporting IPv4 and IPv6 protocols exist logically. A terminal supporting this dual stack technology is referred to as a dual stack terminal.
Due to users' demands for high quality Internet services, improvement of the performance of mobile terminals, such as portable computers and personal digital assistant (PDAs), development of wireless communication technologies, increasing wireless uses, and availability of mobility for next-generation terminals, mobile IPv4 and IPv6 protocols supporting mobility have been introduced as the number of mobile terminals and home appliances on home networks has increased.
Accordingly, if a dual stack terminal is introduced, an environment in which this dual stack terminal moves will also be considered. When a dual stack terminal moves, movement to an IPv4-only network or an IPv6-only network as well as movement between IPv4/IPv6 dual networks, may also be considered.
In the movement of the dual stack terminal, a conventional network-based supporting method cannot support mobility of the dual stack terminal to an IPv4-only network or an IPv6-only network. This is because the conventional network-based mobility supporting method allows only an IPv4 terminal to move to an IPv4-only network, and allows only an IPv6 terminal to move to an IPv6-only network. Accordingly, the conventional network-based mobility supporting method cannot support IP connectivity for a terminal supporting an IPv4/IPv6 dual stack, when the terminal freely moves to an IPv4-only network or an IPv6-only network.
The present invention provides an apparatus for and method of supporting network-based mobility for a dual stack terminal which moves from one network to another network.
According to the present invention, a mobility anchor point (MAP) used in a conventional network-based mobility supporting method is extended and named as a global MAP (GMAP). When a mobile node moves between different network-based localized mobility management domains, such as an IPv4-only network or an IPv6-only network, a binding management message is made to be exchanged between two MAPs of the networks, thereby maintaining a binding cache, including information on the mobile node, between the GMAP and the MAP of the network to which the mobile node has moved, and connecting data transmitted to the GMAP through IPv6-in-IPv4 tunneling or IPv4-in-IPv6 tunneling to the MAP. In this way, even when the dual stack terminal moves from one network to another network, such as an IPv4-only network or an IPv6-only network, communication with an external terminal is enabled.
According to an aspect of the present invention, there is provided mobility anchor point (MAP) apparatus for supporting mobility of a dual stack terminal when the dual stack terminal moves from one network to which the dual stack terminal belonged to another network, the MAP apparatus including a storage unit storing binding information, including information on the dual stack terminal after the moving and information on an access router to which the dual stack terminal belongs, which is received from a first MAP, which is a MAP for the network to which the dual stack terminal has moved; and a transmission unit, which when data to be transmitted to the dual stack terminal is received, transmits the received data to the first MAP based on the binding information on the dual stack terminal stored in the storage unit.
According to another aspect of the present invention, there is provided a method of binding of a dual stack terminal when the dual stack terminal has moved from a network to which the dual stack terminal belonged previously to another network to which the dual stack terminal belongs, the binding method including a first MAP, which is a MAP in the network to which the dual stack terminal belonged previously, the first MAP receiving binding information, including information on the dual stack terminal after the moving and information on an access router to which the dual stack terminal belongs, from a second MAP, which is a MAP of the network to which the dual stack terminal belongs; and the first MAP storing and keeping the received binding information as binding information on the dual stack terminal.
According to another aspect of the present invention, there is provided method of transmitting data to a dual stack terminal when the dual stack terminal has moved from a network to which the dual stack network belonged previously, to another network to which the dual stack network belongs, the method including a first MAP, which is a MAP in the network to which the dual stack terminal belonged previously before the moving, and retains binding information, including information on the dual stack terminal after the moving and information on an access router to which the dual stack terminal belongs, the first MAP receiving data to be transmitted to the dual stack terminal; based on the binding information on the dual stack terminal, the first MAP confirming a second MAP, which is a MAP of the network to which the dual stack terminal has moved, and transmitting the data to the second MAP; and the second MAP receiving the transmitted data, transferring the received data to the dual stack terminal through the access router to which the dual stack terminal belongs.
The apparatus for and method of supporting network-based mobility for a dual stack terminal described above solves the problem of the conventional method in which when a dual stack terminal moves to an IPv4-only network or an IPv6-only network, communication between networks cannot be supported. Accordingly, a dual stack terminal can freely move between IPv4-only networks and IPv6 networks, and seamless communication with an external IPv4 node or IPv6 node is enabled.
According to the present invention, a mobility anchor point (MAP) used in a conventional network-based mobility supporting method is extended and named as a global MAP (GMAP). When a mobile node moves between different network-based localized mobility management domains, such as an IPv4-only network or an IPv6-only network, a binding management message is made to be exchanged between two MAPs of the networks, thereby maintaining a binding cache, including information on the mobile node, between the GMAP and the MAP of the network to which the mobile node has moved, and connecting data transmitted to the GMAP through IPv6-in-IPv4 tunneling or IPv4-in-IPv6 tunneling to the MAP. In this way, even when the dual stack terminal moves from one network to another network, such as an IPv4-only network or an IPv6-only network, communication with an external terminal is enabled.
According to an aspect of the present invention, there is provided mobility anchor point (MAP) apparatus for supporting mobility of a dual stack terminal when the dual stack terminal moves from one network to which the dual stack terminal belonged to another network, the MAP apparatus including a storage unit storing binding information, including information on the dual stack terminal after the moving and information on an access router to which the dual stack terminal belongs, which is received from a first MAP, which is a MAP for the network to which the dual stack terminal has moved; and a transmission unit, which when data to be transmitted to the dual stack terminal is received, transmits the received data to the first MAP based on the binding information on the dual stack terminal stored in the storage unit.
According to another aspect of the present invention, there is provided a method of binding of a dual stack terminal when the dual stack terminal has moved from a network to which the dual stack terminal belonged previously to another network to which the dual stack terminal belongs, the binding method including a first MAP, which is a MAP in the network to which the dual stack terminal belonged previously, the first MAP receiving binding information, including information on the dual stack terminal after the moving and information on an access router to which the dual stack terminal belongs, from a second MAP, which is a MAP of the network to which the dual stack terminal belongs; and the first MAP storing and keeping the received binding information as binding information on the dual stack terminal.
According to another aspect of the present invention, there is provided method of transmitting data to a dual stack terminal when the dual stack terminal has moved from a network to which the dual stack network belonged previously, to another network to which the dual stack network belongs, the method including a first MAP, which is a MAP in the network to which the dual stack terminal belonged previously before the moving, and retains binding information, including information on the dual stack terminal after the moving and information on an access router to which the dual stack terminal belongs, the first MAP receiving data to be transmitted to the dual stack terminal; based on the binding information on the dual stack terminal, the first MAP confirming a second MAP, which is a MAP of the network to which the dual stack terminal has moved, and transmitting the data to the second MAP; and the second MAP receiving the transmitted data, transferring the received data to the dual stack terminal through the access router to which the dual stack terminal belongs.
The attached drawings for illustrating preferred embodiments of the present invention are referred to in order to gain a sufficient understanding of the present invention, the merits thereof, and the objectives accomplished by the implementation of the present invention. Hereinafter, the present invention will be described in detail by explaining preferred embodiments of the invention with reference to the attached drawings.
Here, terms that will be frequently used include network-based localized mobility management (NetLMM), dual stack nodes, an IPv4-only network, an IPv6-only network, a mobile node (MN), a corresponding node (CN), binding management, and a binding cache. In particular, the MN indicates a host or terminal which moves a position from which it accesses a network and the CN indicates a host or a terminal communicating with the MN. The concept of binding is matching a home address of an MN to a communication network when the MN has moved to an external network from the communication network.
The current embodiment of the present invention is a method of seamlessly maintaining an existing communication connection, as illustrated in
In case 1, when the MN has moved to the IPv4-only network, a GMAP which manages the dual stack network before the movement exchanges information of the moved MN, information on an access router corresponding to the MN, and information on the movement to the IPv4-only network, in the form of a binding management message, with a mobility anchor point (MAP) responsible for management of network-based mobility of the IPv4-only network. The GMAP maintains the information in the form of a binding cache.
Accordingly, if actual data is transmitted to the GMAP, the GMAP learns from the binding cache that the MN does not exist under its management and that the MN has moved and is now under management of the new MAP in the IPv4-only network. If the data transmitted to the GMAP is an IPv4 packet, the packet is transmitted to the MAP in the IPv4-only network through IPv4-in-IPv4 tunneling, and if the data is an IPv6 packet, the packet is transmitted to the MAP through IPv6-in-IPv4 tunneling. In this way, even when the dual stack terminal moves to the IPv4-only network, communication can be maintained seamlessly.
In case 2, when the MN has moved to the IPv6-only network, the GMAP which manages the dual stack network before the movement exchanges information of the moved MN, information on an access router corresponding to the MN, and information on the movement to the IPv6-only network, in the form of a binding management message, with a MAP responsible for management of network-based mobility of the IPv6-only network. The GMAP maintains the information in the form of a binding cache.
Accordingly, if actual data is transmitted to the GMAP, the GMAP learns from the binding cache that the MN does not exist under its management and that the MN has moved and is now under management of the new MAP in the IPv6-only network. If the data transmitted to the GMAP is an IPv4 packet, the packet is transmitted to the MAP in the IPv6-only network through IPv4-in-IPv6 tunneling, and if the data is an IPv6 packet, the packet is transmitted to the MAP through IPv6-in-IPv6 tunneling. In this way, even when the dual stack terminal moves to the IPv6-only network, communication can be maintained seamlessly.
As the term ‘tunneling technology’ indicates, a tunnel is made in an IPv4 network and an IPv6 packet is allowed to pass through the IPv4 network, when the IPv6 packet moves from an IPv6 network to another IPv6 network through the IPv4 network. For example, the IPv4/IPv6 dual stack terminal encapsulates IPv6 data in an IPv4 packet, and can transmit the data through an IPv4 routing topology area, by using the tunneling technology.
A dual stack terminal moves from an access router to which the dual stack terminal belongs and from a MAP 210 managing the access router, to another network. The structure of the MAP 210 for supporting mobility of the dual stack terminal is illustrated in
The MAP 210 includes a storage unit 211 storing binding information, including information on the dual stack terminal after the moving and information on an access router to which the dual stack terminal belongs, which is received from a first MAP 220, which is a MAP for the network to which the dual stack terminal has moved. The MAP 210 also includes a transmission unit 212, which when data to be transmitted to the dual stack terminal is received, transmits the data to the first MAP 220 based on the binding information on the dual stack terminal stored in the storage unit 211. With this structure, the MAP 210 performs a role of a GMAP supporting mobility of the dual stack terminal. In particular, the network to which the dual stack terminal belonged before is an IPv4/IPv6 dual network, and the network to which the dual stack terminal has moved is an IPv4 network or an IPv6 network. The storage unit 211 stores the received binding information using a binding cache.
According to the current embodiment, a first MAP, which is a MAP in a network to which the dual stack terminal belonged before, receives binding information, including information on the dual stack terminal after the moving and information on an access router to which the dual stack terminal belongs, from a second MAP, which is a MAP of the network to which the dual stack terminal belongs, in operation 301. Then, the binding information is stored and kept as binding information on the dual stack terminal in operation 302.
The message transfer procedure relates to case 1 described above with reference to
First, if the dual stack node (MN) moves into the IPv4-only network, the MN transmits a registration message to an access router 3 (AR3) according to a network-based mobility support management method. The AR3 receiving the message transmits an Update (AR3, MN) message to the MAP1. The MAP1 receiving the message transfers a binding management (MAP1, AR3, MN) message to the GMAP according to the method of the present invention. The GMAP receiving the message maintains the mobility information of the MN, that is, (MAP1, AR3, MN, v4) information, in the form of a binding cache.
The message transfer procedure relates to case 2 described above with reference to
If the dual stack node (MN) moves into the IPv6-only network, the MN first transmits a registration message to an access router 5 (AR5) according to a network-based mobility support management method. The AR5 receiving the message transmits an Update (AR5, MN) message to the MAP2. Then, the MAP2 receiving the message transfers a binding management (MAP2, AR5, MN) message to the GMAP according to the method of the present invention. The GMAP receiving the message maintains the mobility information of the MN, that is, (MAP2, AR5, MN, v6) information, in the form of a binding cache.
Referring to
Referring to
According to the current embodiment, a first MAP, which is a MAP in a network to which the dual stack terminal belonged before the moving and which stores binding information, including information on the dual stack terminal after the moving and information on an access router to which the dual stack terminal belongs, receives data to be transmitted to the dual stack terminal in operation 801. Based on the binding information on the dual stack terminal, the first MAP confirms a second MAP, which is a MAP of the network to which the dual stack terminal has moved, and transmits the data to the second MAP in operation 802. Then, the second MAP transfers the received data to the dual stack terminal through the access router to which the dual stack terminal belongs in operation 803.
The apparatus for and method of supporting network-based mobility for a dual stack terminal described above solves the problem of the conventional method in which when a dual stack terminal moves to an IPv4-only network or an IPv6-only network, communication between networks cannot be supported. Accordingly, a dual stack terminal can freely move between IPv4-only networks and IPv6 networks, and seamless communication with an external IPv4 node or IPv6 node is enabled.
The present invention can also be embodied as computer readable codes on a computer readable recording medium. The computer readable recording medium is any data storage device that can store data which can be thereafter read by a computer system. Examples of the computer readable recording medium include read-only memory (ROM), random-access memory (RAM), CD-ROMs, magnetic tapes, floppy disks, optical data storage devices, and carrier waves (such as data transmission through the Internet). The computer readable recording medium can also be distributed over network coupled computer systems so that the computer readable code is stored and executed in a distributed fashion. Also, functional programs, codes, and code segments for accomplishing the present invention can be easily construed by programmers skilled in the art to which the present invention pertains.
While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present invention as defined by the following claims. The preferred embodiments should be considered in descriptive sense only and not for purposes of limitation. Therefore, the scope of the invention is defined not by the detailed description of the invention but by the appended claims, and all differences within the scope will be construed as being included in the present invention.
The present invention provides an apparatus for and method of supporting network-based mobility for a dual stack terminal which moves from one network to another network.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10-2006-0054908 | Jun 2006 | KR | national |
| 10-2006-0124147 | Dec 2006 | KR | national |
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/KR2007/002856 | 6/13/2007 | WO | 00 | 12/18/2008 |
