JP4319842B2 - Mobile communication system with proxy location registration option - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a mobile communication system in which a mobile node performs location registration in order to communicate with other communication nodes, and more particularly, wasteful communication by performing proxy location registration for a plurality of mobile nodes onboard a vehicle. It is related with the technology which controls.
[0002]
[Prior art]
In a mobile communication system, since a mobile node, that is, a mobile terminal moves spatially, in order to communicate with such a mobile node, the network in the mobile communication system must always know the position of the mobile node. . For this reason, each mobile node needs to perform location registration with a server or the like connected to the network.
[0003]
Here, with reference to FIG. 4, a schematic configuration of a mobile communication system using the HMIPv6 protocol is shown as a conventional mobile communication system.
The mobile communication system of FIG. 4 includes a home agent (HA) 1 and a plurality of mobility anchor points (MAP) linked to the home agent 1 via a segment 1a. In FIG. 4, only one mobility anchor point 1 (MAP1) 3a is shown.
[0004]
The segment 1a linked to the home agent 1 is linked to another segment 1b via the router 9, the network 7 and another router 11, and a corresponding node (CN) 5 as a communication partner is linked to the link 1b. ing. The network 7 can be considered as an arbitrary topology including, for example, a router and a link.
[0005]
Furthermore, in FIG. 4, it is assumed that the mobile node (MN) 19 is located in an area where communication with the mobility anchor point 1 (MAP1) 3a is possible. When the mobile node (MN) 19 moves to another area, the mobility anchor point (MAP) corresponding to the area communicates with the mobile node 19.
[0006]
In the mobile communication system of FIG. 4, MAP1 (3a) broadcasts information on MAP1 (3a) including router advertisement (RA) in a corresponding area. The mobile node 19 receives this information and obtains the current location (LCoA1) of the mobile node and the address (RCoA) of MAP1.
[0007]
Next, the mobile node 19 transmits a binding update (BU), that is, a location registration message, to the MAP1, and the MAP1 returns a binding acknowledgment (BA). As a result, the current location information LCoA1 is stored in the cache of MAP1, that is, the binding cache (location registration information memory), corresponding to the home address of the mobile node 19.
[0008]
Next, the mobile node 19 sends a location registration message (BU) to the home agent (HA) 1. The home agent 1 performs address duplication check (DAD) and returns a binding acknowledgment (BA) to the mobile node 19 if there is no abnormality. As a result, the address of MAP 1 is stored in the binding cache of home agent 1 corresponding to the home address of mobile node 19.
[0009]
Under such circumstances, if the corresponding node (CN) 5 transmits a packet including the address information of the mobile node 19 to communicate with the mobile node 19, the packet passes through the router 11, the network 7 and the router 9. To the home agent 1. The home agent 1 checks the location of the mobile node 19 from the transmitted packet data and knows that the mobile node 19 is in a position where it can communicate with the MAP 1. As a result, packet data is sent from the home agent 1 to the mobile node 19 via the MAP 1.
[0010]
In response to this, the mobile node 19 sends a location registration message (BU) to the corresponding node (CN) 5. Then, desired packet data is sent from the corresponding node 5 to the mobile node 19 via MAP1. In this way, communication between the corresponding node 5 and the mobile node 19 becomes possible.
[0011]
By the way, in response to the explosive increase of today's mobile terminals, the location registration area is getting smaller and smaller. In particular, in urban areas where the density of users is very high, location registration of users who use mobile nodes is frequently performed.
[0012]
In MIPv6 and HMIPv6, which are conventional Internet protocol (IP) standards, location registration is performed individually from the mobile node side. Therefore, it is necessary to sequentially update the position registration by sending a position registration message (BU) as the mobile node moves.
[0013]
Here, consider a case where a large number of mobile nodes, that is, mobile terminals, are present at a high density in a narrow space such as a vehicle such as a commuter train, and the vehicle is moving. In such a case, a location registration request for the home network of many mobile nodes is generated. In this case, the communication traffic of the mobile node itself may be very low.
[0014]
As another prior art, for example, one described in Patent Document 1 is known.
[Patent Document 1]
US Pat. No. 6,580,916 B1 [Problems to be Solved by the Invention]
In such a case, location registration request traffic to the home network occurs explosively, and therefore spectrum resources are insufficient.
[0015]
In order to solve this problem, it has been proposed to collectively register the positions of a plurality of mobile nodes that board the vehicle.
[0016]
However, in such a proposal, it has not yet been proposed how to specifically perform location registration of a plurality of mobile nodes.
[0017]
The present invention provides a proxy location registration unit in a mobile communication system and proposes a specific procedure for performing proxy location registration.
[0018]
Therefore, an object of the present invention is to enable a mobile communication system to perform proxy location registration for a plurality of mobile nodes mounted on a vehicle or the like while maintaining a simple configuration and compatibility with an existing system. An object of the present invention is to be able to suppress useless communication for location registration.
[0019]
[Means for Solving the Problems]
According to an aspect of the present invention, the mobile node includes at least one server that performs location registration in order to communicate with another communication node, and the communication node and the communication node based on the location information of the mobile node registered in the server A mobile communication system for communicating with a mobile node is provided, and the mobile communication system includes a vehicle proxy position registration unit (VPLR) that performs proxy position registration for a mobile node that has boarded the vehicle. Unit transmits a router advertisement message including information (PLR option) indicating that proxy position registration is possible, and the mobile node that has boarded the vehicle receives the router advertisement message from the vehicle proxy position registration unit, And information indicating that the vehicle proxy location registration unit requests proxy location registration instead of direct location registration to the server. The mobile node can communicate with another communication node via the vehicle proxy location registration unit by sending a physical location registration request to the vehicle proxy location registration unit and requesting proxy location registration. To do.
[0020]
In this case, the mobile node first communicates with the other communication node via the vehicle proxy location registration unit and the server, and then passes through the vehicle proxy location registration unit without passing through the server. It can be configured to communicate with a communication node.
[0021]
In addition, it is convenient that the vehicle proxy location registration unit sends the location registration information of a plurality of mobile nodes that have boarded the vehicle as a list to the server.
[0022]
After the mobile node has boarded the vehicle, the vehicle proxy location registration unit is responsive to a reception signal including a router advertisement message from the vehicle proxy location registration unit being stronger than a reception signal from another server. Can be configured to send the proxy location registration request.
[0023]
The server is a home agent, and the home agent can be linked to the vehicle proxy position registration unit and linked to another communication node via another link.
[0024]
The home agent may be linked to a plurality of mobility anchor points, and the vehicle proxy location registration unit may be linked to the home agent via the mobility anchor point.
[0025]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.
FIG. 1 shows a schematic configuration of a mobile communication system according to an embodiment of the present invention. In the mobile communication system of FIG. 1, in addition to the configuration of the mobile communication system of FIG. 4, a vehicle proxy location registration unit (VPLR) 17 provided in the vehicle 15 is shown. Other parts are the same as those in the system of FIG. 4, but FIG. 1 shows another MAP2 (3b) as a mobility anchor point (MAP) in addition to MAP1 (3a).
[0026]
In the mobile communication system of FIG. 1, before the mobile node 19 (MN) gets on the vehicle, the same operation as described above with reference to FIG. 4 is performed, and between the corresponding node 5 and the mobile node 19. Communication is performed via MAP1, for example.
[0027]
However, in this case, the vehicle proxy position registration unit (VPLR) 17 is a router, but performs the same operation as the mobile node 19 with respect to communication from the host. That is, the VPLR 17 registers the location with the MAP 1 in the same manner as described above with respect to the mobile node 19. Therefore, an address (VCoA1) indicating the current position of VPLR is stored in the binding cache of MAP1 corresponding to the home address of VPLR.
[0028]
Next, the VPLR 17 registers the location with the home agent 1 in the same manner.
[0029]
Next, the VPLR 17 broadcasts a router advertisement (RA). This router advertisement includes, for example, 1-bit PLR option information in addition to various information, as shown in FIG. That is, the VPLR 17 announces that it can perform proxy location registration by broadcasting such a router advertisement (RA) with the PLR option.
[0030]
Next, it is assumed that the mobile node 19 has boarded the vehicle 15 but the vehicle 15 has not yet started moving. In this state, MAP1 broadcasts MAP1 information together with the router advertisement. The VPLR 17 periodically broadcasts MAP1 and VPLR information together with router advertisements. This router advertisement includes a PLR option.
[0031]
In this case, since the mobile node 19 has only one interface (I / F), the mobile node 19 cannot receive the router advertisement from the VPLR 17. Therefore, the mobile node 19 does not change its own address from the corresponding MAP MAP1. Therefore, in this state, the packet is communicated from the corresponding node 5 to the mobile node 19 via the home agent 1 (initially only) and MAP1.
[0032]
Next, a case where a vehicle on which the user carrying the mobile node 19 has boarded, for example, a train, starts running will be described with reference to FIG. In this case, it is assumed that the vehicle 15 moves from the coverage area of MAP1 to the coverage area of MAP2.
[0033]
The VPLR 17 has a plurality of interfaces for communicating with the upper router, and can therefore receive router advertisements (RA) from both MAP1 and MAP2. Thus, VPLR 17 can have two current positions (LCoA), namely VCoA1 and VCoA2, which correspond to the addresses of MAP1 and MAP2, respectively.
[0034]
As the vehicle moves, the router advertisement from MAP2 becomes stronger and the router advertisement from MAP1 becomes weaker. Therefore, VPLR 17 selects MAP2 as its own MAP, and handover is performed.
[0035]
The VPLR 17 sends its own location registration message (BU) to MAP1, MAP2 and home agent (HA) 1. Next, the VPLR 17 broadcasts a router advertisement having a PLR option as shown in FIG.
[0036]
On the other hand, the operation of the mobile node 19 boarding the vehicle 15 will be described. The vehicle 15 is moving from the coverage area of MAP1 toward the coverage area of MAP2. In such a state, the router advertisement (RA) received from the MAP 1 received by the mobile node 19 becomes weaker. Therefore, the mobile node 19 operates another router advertisement and detects the router advertisement from the VPLR 17 as a stronger signal.
[0037]
The mobile node 19 detects the PLR option included in the router advertisement of the VPLR 17 and knows that the VPLR 17 can register the proxy location. Then, the current position (LCoA2: static address) of the mobile node 19 is acquired, and a position registration message (BU) is transmitted to the VPLR 17. Accordingly, the home address of the mobile node 19 and the current position (LCoA2) are stored in the binding cache of the VPLR 17 in correspondence with the home address.
[0038]
Since the mobile node 19 understands that the PLR option is set by the router advertisement from the VPLR 17 as described above, that is, the proxy location registration is possible, the mobile node 19 sends a location registration message (BU). In HMIPv6, instead of sending it to the home agent 1 and the corresponding node (CN) 5 by itself, it sends it to the VPLR 17.
[0039]
3A and 3B show schematic formats of a router advertisement from VPLR 17 and a location registration message (BU) from mobile node 19, respectively. In FIG. 3A, the router advertisement from VPLR 17 includes the PLR option as described above. The PLR option is, for example, 1-bit data. When this data is “1”, it indicates that proxy position registration is possible, and when it is “0”, it indicates that proxy position registration is not possible. Constitute.
[0040]
In contrast, the location registration message from the mobile node 19 shown in FIG. 3B, that is, the binding update (BU), similarly includes, for example, 1-bit data as PLR option data. For example, when the 1-bit data is “1”, it indicates that the mobile node 19 requests the VPLR 17 to perform proxy location registration, and when it is “0”, it indicates that the proxy location registration is not requested. be able to.
[0041]
Next, when receiving the location registration message (BU) as described above from the mobile node 19, the VPLR 17 transmits the location registration message to the home agent 1. Thereby, for example, packet communication from the corresponding node (CN) 5 to the mobile node 19 is guided to the corresponding node 5, the home agent 1, the VPLR 17, and the mobile node 19.
[0042]
Next, the VPLR 17 transmits a location registration message (BU) of the mobile node 19 to the corresponding node (CN) 5. Thereafter, packet communication between the mobile node 19 and the corresponding node 5 is guided to the corresponding node 5, the VPLR 17, and the mobile node 19.
[0043]
In the above description, the case where there is only one mobile node 19 on the vehicle 15 has been described, but in reality, a plurality of or many mobile nodes (MN) can be mounted on the vehicle 15. Therefore, the VPLR 17 can collectively transmit a plurality of mobile node location registration messages to the home agent 1 or MAP 2. That is, the VPLR 17 can collectively send information such as home addresses and current positions of a plurality of mobile nodes in a table or list format, for example.
[0044]
As the vehicle 15 continues to move further, the current position (LCoA) of the VPLR 17 continues to change. For example, VCoA3 changes to VCoA3,..., VCoA10 (not shown).
[0045]
However, the current position (LCoA) of the mobile node 19 does not change as long as it is on the same vehicle 15, and remains LCoA2.
[0046]
As for signal communication (signaling) for communication control, the mobile node 19 only has to send a position registration message (BU) to the VPLR 17 for the first time. There is no need to send. In addition, regarding the transmission of the location registration message from the mobile node 19 to the home agent 1 and from the mobile node 19 to the corresponding node 5, the VPLR 17 acts as a proxy for the transmission of these location registration messages. During this time, the mobile node 19 itself does not need to send such a location registration message to the home agent 1 and the corresponding node 5, respectively. Moreover, the VPLR 17 can transmit a large number of, for example, 100 individual location registration messages of the mobile node at a time. Therefore, the amount of packet communication can be surely reduced especially when the vehicle 15 travels a certain distance.
[0047]
When the mobile node 19 gets off the vehicle 15 together with the user, the operation based on the HMIPv6 described first is performed again.
[0048]
【The invention's effect】
As is clear from the above, if a vehicle equipped with a mobile node travels a long distance, the communication traffic of location registration messages between the mobile node and the home agent and between the mobile node and the corresponding node can be greatly reduced.
[0049]
A packet for a mobile node that has boarded the vehicle is relayed by VPLR. For this reason, various information can be sent in addition to the information from the corresponding node using VPLR. For example, news, advertisements, local information, and the like can be efficiently transmitted to a plurality of mobile nodes in the vehicle.
[0050]
In addition, the operation mode of the mobile node can be automatically controlled by the control from the VPLR. For example, the mobile node of the user who has boarded the vehicle can be set to the vibration mode instead of the ring tone.
[0051]
Furthermore, appropriate location information of each mobile node can be sent from the VPLR to the home agent or the like. That is, the current position of each mobile node is not transmitted, but information that the mobile node is on a vehicle such as a train can be provided.
[0052]
For an old mobile node that does not have a function of requesting proxy location registration, the communication system can perform the same operation as the conventional one based on the traditional HMIPv6. Furthermore, because VPLR has two interfaces (I / F), it is convenient for packet forwarding and soft handover of the mobile node. Further, no change is required for the MAP.
[Brief description of the drawings]
FIG. 1 is an explanatory block diagram showing a schematic configuration of a mobile communication system according to an embodiment of the present invention.
FIG. 2 is an explanatory block diagram showing an operation when a vehicle moves from an initial position in the communication system of FIG. 1;
FIG. 3 is an explanatory diagram showing a schematic format of a router advertisement (a) from a vehicle proxy position registration unit and a position registration message (b) from a mobile node.
FIG. 4 is an explanatory block diagram showing a schematic configuration of HMIPv6 as a conventional mobile communication system.
[Explanation of symbols]
1 Home Agent (HA)
3a, 3b Mobility anchor point (MAP)
5 Corresponding node (CN)
7 Network 9, 11 Router 15 Vehicle 17 Vehicle Proxy Location Registration Unit (VPLR)
19 Mobile node (MN)

Claims (5)

Mobile communication comprising at least one server that performs location registration so that a mobile node communicates with another communication node, and communication between the communication node and the mobile node based on location information of the mobile node registered in the server A system,
A vehicle proxy position registration unit (VPLR) that is provided in a vehicle on which a plurality of mobile nodes can be boarded, and performs proxy position registration for the mobile node boarding the vehicle;
The vehicle proxy location registration unit transmits a router advertisement message including information (PLR option) indicating that proxy location registration is possible,
A mobile node that has boarded the vehicle receives a router advertisement message from the vehicle proxy location registration unit, and requests the vehicle proxy location registration unit to perform proxy location registration instead of direct location registration to the server. By sending a proxy location registration request including information to the vehicle proxy location registration unit and requesting proxy location registration, the mobile node and other communication nodes can communicate with each other via the vehicle proxy location registration unit,
The mobile node registers the proxy location in the vehicle proxy location registration unit in response to a received signal including a router advertisement message from the vehicle proxy location registration unit becoming stronger than other received signals from the server. Ask
The mobile communication system according to claim 1, wherein the proxy location registration request includes information indicating whether the mobile node requests the vehicle proxy location registration unit to perform proxy location registration .   The mobile node first communicates with the other communication node via the vehicle proxy location registration unit and the server, and then communicates with the other communication node via the vehicle proxy location registration unit without going through the server. The mobile communication system according to claim 1, wherein communication is performed.   2. The mobile communication system according to claim 1, wherein the vehicle proxy location registration unit sends location registration information of a plurality of mobile nodes mounted on the vehicle to the server as a list. 2. The movement according to claim 1, wherein the server is a home agent, and the home agent is linked to the vehicle proxy location registration unit and linked to another communication node via another link. Wireless system . The mobile radio system according to claim 4, wherein the home agent is linked to a plurality of mobility anchor points, and the vehicle proxy position registration unit is linked to the home agent via the mobility anchor points .

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