JPH05227161A - System and device for mobile communication control - Google Patents

Abstract

PURPOSE:To provide the system and device for mobile communication control allowing the objective node to correctly receive a node sending packets to mobile nodes moving in the network to the accompaniment of the change of address by quickly changing the transmission destination of packets corresponding to the movement. CONSTITUTION:A general node mobile communication controller holds the correspondence of address before and after the movement of mobile nodes in a data section 1. A mobile address processing section 3 takes the packet transmission destination address for mobile nodes as a moved address, adding an address to be moved as additional information to be converted into a marked packet. The converted packet is sent through a line control section 4.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mobile communication control system and apparatus for communicating with a node which moves between networks with a change of address.

[0002]

2. Description of the Related Art Conventionally, a communication control device does not assume that a partner node with which it wishes to communicate moves, and even if the partner node moves to another network, it moves until the position information is updated manually. The packet does not reach the destination node because it continues to send to the previous address.

An example of the above-described conventional communication at the time of node movement will be described below with reference to the drawings. 12
Indicates a case where communication cannot be performed when the node moves. The mobile node has an address α when connected to the network A and an address β when connected to the network B. It is assumed that the mobile node moves from network A to network B. Before the node X knows the address β, which is the new address of the mobile node, it sends a packet specifying the address α to communicate with the mobile node, and a transmission error occurs. Node X
After the mobile node knows the new address of the mobile node, it can send a packet specifying the address β, and can normally communicate with the mobile node.

[0004]

(1) Problem 1 In the conventional system as described above, as described above, in order to continue sending packets to the original old address even if the node of the communication partner moves, There was a problem that the packet did not reach the partner node.

(2) Problem 2 Further, for a node that wants to communicate with a moving node continuously before and after moving, it is not enough to receive packets from the mobile node. In other words, there is a problem in that a packet cannot be recognized as a partner with whom the mobile node has communicated before the movement unless it is a packet whose source is the address before the movement of the mobile node.

(3) Problem 3 Further, in the case where the mobile node repeats the movement in multiple stages, if the latest address information of the mobile node is not propagated promptly, another node trying to communicate with the mobile node. Has a problem that it keeps sending packets to the old address for a long time, and thus a large number of packets may be lost.

In view of the above problems, the present invention ensures that even if a node of a communication partner moves, the destination of a packet is correctly received by the target node by rapidly changing the destination of the packet in response to the movement. An object of the present invention is to provide a mobile communication control method and a mobile communication control device that enable the mobile communication control method.

[0008]

Means for Solving the Problems (1) Means 1 A mobile communication control method of the present invention for solving the above-mentioned problem 1 is a method in which a first node of a communication partner moves between networks before moving. The second node, which attempts to transmit a packet to the address of the first node, receives the address correspondence from the node holding the correspondence between the addresses before and after the movement of the first node. Process,
A step of holding the correspondence of the addresses, a step of converting a packet addressed to the address of the first node before movement to a packet addressed to the address after movement based on the correspondence of the addresses, and the packet subjected to the conversion From the node holding the correspondence between the addresses before and after the movement of the first node by the gateway directly connected to the network to which the address before the movement of the first node belongs. Receiving address correspondence, and when receiving a packet addressed to the address before the movement of the first node, transmitting the address correspondence to the source node of the packet, that is, the second node. This is a mobile communication control method for performing.

(2) Means 2 In the mobile communication control system of the present invention for solving the above-mentioned problem 2, the first node is moved by the second node which tries to transmit the packet to the first node which has moved. Converting a packet addressed to the address before the movement of the first node into a marked packet addressed to the address after the movement based on the correspondence between the address before the movement of the node and the address after the movement of the node; and converting the packet into the marked packet Performing the step of adding the previous destination address and the step of sending the marked packet;
When the first node receives the marked packet, the first node restores the unconverted packet from the marked packet, and the destination address of the restored packet is marked with the marked packet. Returning to the untranslated destination address added to the packet, the first node attempts to send the packet to the second node in response to the marked packet. In this case, a step of adding the pre-translation destination address in the received packet as a pre-translation source address and sending the packet as a marked packet is performed, and the first node causes the first node to When attempting to send a packet to the node with which it was communicating before the move, the first node holds it. Among the correspondence between the addresses before and after the movement, the packet whose source address is the address used by the partner node as the address of the first node is converted into the packet originating from the address after the movement, and When the second node which is the destination of the marked packet receives the marked packet, the step of adding the source address and transmitting the marked packet is performed by the second node. In the mobile communication control method, a step of restoring the unconverted packet from the marked packet and a step of returning the source address of the restored packet to the untranslated source address added to the marked packet is there.

(3) Means 3 In the mobile communication control method of the present invention for solving the above-mentioned problem 3, the first node, which is a mobile node, causes all the pre-movement addresses of the first node itself and the current address. The step of holding the address and the set of the correspondence between the addresses before and after the movement of the first node and the address before the movement in the previous movement if not the first movement are The step of transmitting to the gateway directly connected to the network to which it belongs, by the gateway,
Receiving the set of addresses, and retaining the set of addresses having a pre-movement address that matches the pre-movement address among the received correspondences of the pre-movement and post-movement addresses If the pre-movement address of the received address set matches the post-movement address of the held address set, the held address Replacing the post-movement address of the set with the post-movement address of the received address set, and the correspondence of the post-movement address to the network to which the previous pre-movement address in the set to which the correspondence of the replaced address belongs belongs. This is a mobile communication control system that performs the step of transmitting to a gateway that is directly connected.

(4) Means 4 In the mobile communication control system of the present invention, the means 3 is further supplemented so that the correspondence between the addresses of the first node itself before and after the movement can be determined by the first node. The step of transmitting to all the nodes directly connected to the network to which the node belongs, and the node that receives the correspondence causes the corresponding post-movement address of the address already held by the node to
This is a mobile communication control system that performs a step of replacing the corresponding post-movement address of the held address with the corresponding post-movement address of the received address when the corresponding pre-movement address of the received address matches.

(5) Means 5 In the mobile communication control system of the present invention, means 3 is further supplemented, and the correspondence of the addresses after replacement is made by the gateway before the previous movement in the set to which the correspondence of the replaced addresses belongs. The step of transmitting to all the nodes directly connected to the network to which the address belongs is performed, and by the node which receives the correspondence, the corresponding post-movement address of the address already held by the node corresponds to the correspondence of the received address. This is a mobile communication control method for performing a step of replacing a post-movement address corresponding to a held address with a post-movement address corresponding to a received address when the pre-movement address matches.

(6) Means 6 The mobile communication control device of the present invention embodies the mobile communication control system of means 1, in which the address of a mobile node that holds the correspondence between the address before the move and the address after the move Receiving means for receiving the correspondence of the address, holding means for holding the correspondence of the address, and conversion means for converting the packet addressed to the address before the movement of the mobile node into the packet addressed to the address based on the correspondence of the address. A mobile communication control unit for a general node, which includes a transmitting unit that transmits the packet that has been subjected to the conversion, a receiving unit that receives a correspondence between addresses of the mobile node before and after the movement, and the correspondence is held. When a packet addressed to the address before the movement of the mobile node is received, a pair of the address before and after the movement of the mobile node is transmitted to the source node of the packet. The mobile communication control device comprises a gateway mobile communication control unit including a transmission means for transmitting a response.

(7) Means 7 The mobile communication control apparatus of the present invention embodies the mobile communication control system of means 2. Before the movement of the mobile node based on the correspondence between the addresses before and after the movement of the mobile node. Means for converting the packet addressed to the address to the marked packet addressed to the moved address, adding means for adding the destination address before the conversion to the marked packet, and sending for sending the marked packet Means and the mobile node of the communication partner receives the marked packet with the source address translated from the pre-movement address to the post-movement address and the source address before translation added, Restoration means for restoring the packet, and the source address of the restored packet is added to the marked packet before conversion The mobile communication control unit for a general node having means for returning to the source address of the mobile node, and the mobile node converts the destination address from the pre-movement address to the post-movement address by the correspondent node and When receiving the added marked packet, the restoring means for restoring the unconverted packet from the marked packet, and the transmission before the conversion in which the destination address of the restored packet is added to the marked packet Means to return to the destination address,
When a packet is to be transmitted to the source as a response to the marked packet, the source address is the pre-translation destination address in the received packet, and it is addressed to the node that was communicating before the move. When attempting to send a packet, the source address is the address of the mobile node that the other node uses as the address of the mobile node among the correspondences of the addresses before and after the movement held by the mobile node itself. The apparatus further comprises: a converting unit that converts the packet into a marked packet having a moving address, a adding unit that adds the source address before conversion to the marked packet, and a sending unit that sends the marked packet. The mobile communication control device comprises a mobile communication control unit for a mobile node.

(8) Means 8 The mobile communication control device of the present invention embodies the mobile communication control system of means 3, and the correspondence between the addresses of the mobile node before and after the movement and the movement of the mobile node is the first time. If it is not a move, the receiving means for receiving the set of the pre-movement address in the previous move and the set of addresses having the pre-movement address matching the pre-movement address among the received correspondences of the pre-movement address and the post-movement address are held If not, the holding means for holding the correspondence of the address, and if the address set is already held, the pre-movement address of the received address set is moved to the held address set. Replacement means for replacing the post-movement address of the held address set with the post-movement address of the received address set when the post-replacement address matches the post-movement address; A mobile communication control unit for a gateway having a transmitting means for transmitting to a gateway directly connected to a network to which the previous pre-movement address of the pair of addresses holding the correspondence and the mobile node are And a correspondence between the address after the move and a set of the address before the move in the previous move if the move is not the first move, and the set of the address belongs to the address before the move in the set of the address. A mobile communication control device comprising a mobile communication control unit for a mobile node, the mobile communication control unit including a transmission means for transmitting to a gateway directly connected to a network.

[0016]

(1) Operation 1 According to the present invention, the above-mentioned means 1 allows the second node communicating with the moving first node to change the address even if the first node of the communication partner moves and the address is changed. By receiving and holding the address correspondence from the node holding the correspondence between the pre-movement address and the post-movement address of node 1,
Based on the above correspondence, the packet addressed to the address before the movement of the first node is converted into the packet addressed to the address after the movement and transmitted, and the packet is received by the moved first node.

Further, the gateway, which is directly connected to the network to which the pre-movement address of the moved first node belongs, receives and holds the correspondence between the pre-movement address and the post-movement address of the first node, thereby It is possible to detect that the packet sent to the address before the movement of the node of 1) is a packet to the first node which does not already exist when trying to pass through the gateway. The correspondence between the addresses of the first node before and after the movement will be transmitted to the source node of the packet addressed to the previous address. As a result, the source node of the packet addressed to the pre-movement address of the first node is the first node.
You can find out the new address of your node.

(2) Operation 2 According to the present invention, by the means 2 described above, the second node trying to continue communication from before the movement of the first node to after the movement of the first node is not moved even after the movement of the first node. A packet having the address as the source address can be obtained. As a result, even if the first node moves, the source address of the packet from the first node will be unified with the pre-movement address, and the second node communicating with the first node will move before and after the movement. Thus, continuous communication can be performed with the first node.

(3) Operation 3 According to the present invention, by means 3 described above, the correspondence between the addresses of the mobile node before and after the movement of the mobile node while the mobile node is repeatedly moving is all the networks to which the mobile node once belonged. Even if the mobile node repeats movement in multiple stages, the gateway can quickly know the latest current address of the mobile node even if the mobile node repeats movement in multiple stages. As a result, the node trying to communicate with the mobile node will be correctly notified of the current address even if the packet addressed to the pre-movement address at any stage of the mobile node is transmitted.

(4) Operation 4 According to the present invention, when the mobile node performs multi-step movement by the means 4 described above, the moving node determines the correspondence between the address before the movement and the address after the movement of the mobile node before the movement. By propagating to a node directly connected to the network to which it belongs, said node can quickly know the mobile node's move and pre- and post-movement addresses.

(5) Operation 5 According to the present invention, by means 5 described above, the correspondence between the addresses of the mobile node before and after the movement while the mobile node repeats movement is in all the networks to which the mobile node once belonged. Since it is propagated to all directly connected nodes, even when the mobile node repeats movement in multiple stages, the node can know the latest current address of the mobile node. This allows the node to quickly obtain the latest current address of the mobile node without attempting to communicate with the mobile node.

(6) Operation 6 According to the present invention, by means 6 described above, the general node mobile communication control unit determines the address of the mobile node before the movement based on the correspondence between the addresses of the mobile node before and after the movement. Packet can be converted to a packet addressed to the moved address and sent out, and the gateway mobile communication control unit causes the gateway directly connected to the network to which the moved address of the moved node belongs to By receiving and holding the correspondence between the pre-movement address and the post-movement address, when the packet sent to the pre-movement address of the mobile node tries to pass through the gateway, the packet addressed to the mobile node for which the gateway no longer exists. It is possible to detect that the source node of the packet addressed to the pre-movement address of the mobile node It is possible to notify the address of the address of the mobile node before and after the move.

(7) Operation 7 In the present invention, the means 7 described above causes the general node mobile communication control unit to address the address of the mobile node before the movement based on the correspondence between the addresses of the mobile node before and after the movement. Converts a packet to a marked packet addressed to the moved address, sends the destination address before conversion, and sends the packet.The source address is converted from the pre-movement address to the post-movement address by the correspondent mobile node. When a marked packet with a source address before translation is received, the packet before translation is restored from the marked packet, and the source address of the restored packet is added to the marked packet. It becomes possible to return to the source address before conversion. Furthermore, when the mobile node receives a marked packet from the mobile communication control unit for mobile node, in which the destination address is translated from the pre-movement address to the post-movement address by the correspondent node and the pre-translation destination address is added, , Restores the untranslated packet from the marked packet, returns the destination address of the restored packet to the untranslated destination address added to the marked packet, and sends it as a response to the marked packet Based on the correspondence between the addresses of the mobile node itself before and after the move, when the packet is originally sent and when the packet is sent to the node that was communicating before the move When a packet with a source address before moving is converted into a marked packet with a source address after moving, Wherein adding the source address before conversion to marked packets it is possible to be sent to.

(8) Operation 8 According to the present invention, by means of the means 8 described above, the gateway mobile communication control unit causes the correspondence between the addresses before and after the movement of the mobile node and the movement of the mobile node to be the first movement unless it is the first movement. Of the received address before and after the move, and if it does not hold the set of addresses having the pre-movement address that matches the pre-movement address among the received correspondences of the pre-movement address and the post-movement address, hold it already, When the set of addresses is held, when the pre-movement address of the received set of addresses matches the post-movement address of the set of held addresses, the post-movement address of the set of held addresses To the post-movement address of the received address set, and the previous pre-movement address of the address set holding the correspondence of the post-substitution address belongs to It is possible to propagate to a gateway directly connected to the network. In addition, the mobile node mobile communication control unit causes the mobile node to retain all of its pre-movement addresses and current addresses, and the correspondence between its own pre-movement addresses and post-movement addresses and the previous movement unless it is the first movement. It becomes possible to send the set of the pre-movement address in (1) to the gateway directly connected to the network to which the pre-movement address of the mobile node belongs.

[0025]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A mobile communication control device according to an embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows the configuration of a mobile communication control device according to an embodiment of the present invention. In FIG. 1, 1 is a data section that holds the correspondence between addresses before and after the movement of a mobile node, 2 is a higher-level communication control section that performs connection connection / disconnection, timer monitoring, etc., 3 is the data of the data section 1 A mobile address processing unit for processing a mobile address with reference to 4 is a line control unit for controlling a physical communication line.

FIG. 2, FIG. 3, and FIG. 4 show more detailed device configurations of the mobile communication control devices for mobile node, gateway, and general node, respectively. In FIG. 2, reference numeral 20 is a response packet transmission unit that transmits a response packet to the received packet, and 21 is a marked packet for converting the transmission packets from the response packet transmission unit 20 and the upper communication control unit 2 into a marked packet. It is a conversion unit. 26 is a movement address setting unit for storing the acquired post-movement address in the data unit 1, 27 is a movement notification transmission unit for notifying that the mobile node has moved to another node based on the obtained post-movement address, and 28 is A received packet identification unit for identifying the received packet, and 29 is a marked packet restoration unit for restoring the received marked packet. Reference numeral 25 denotes a post-movement address obtaining means for obtaining the post-movement address of the mobile node, which is means outside the mobile communication control device for the present mobile node.

In FIG. 3, reference numeral 35 is a received packet identification section for identifying a received packet, and 36 is movement notification information for storing the correspondence of the address of the mobile node in the data section 1 based on the received movement notification packet. Processing unit, 3
7 indicates that the destination address of the received packet is the data part 1
The address comparison unit for comparing whether the address is the same as the pre-movement address stored in, the address change notification transmission unit for transmitting the address change notification based on the comparison result in the address comparison unit 37, and the address comparison unit 39. It is a marked packet conversion unit for converting into a marked packet based on the comparison result in 37 and transmitting the packet.

In FIG. 4, reference numeral 45 is a received packet identification unit for identifying a received packet, 46 is a marked packet restoration unit for restoring the received marked packet, and 47 is a move from the received address change notification packet. An address change notification information processing unit for storing the correspondence of the address of the node in the data unit 1, 48 denotes the destination address of the transmission packet received from the higher-level communication control unit 2 of the mobile node stored in the data unit 1. An address comparison unit for comparing whether or not it is equal to the pre-movement address, and 49 is a marked packet conversion unit for converting to a marked packet based on the comparison result in the address comparison unit 48. The operation of the mobile communication control device configured as described above will be described below with reference to FIGS. 5, 6 and 7.

FIG. 5 shows a first operation example in which a packet is transmitted from a general node to an address before movement of a mobile node, and a movement notification is made from a gateway, and the packet moves correctly based on the movement notification. A second operation example until the mobile node is sent to the previous mobile node and a third operation example until the response is sent from the mobile node to the general node are shown. In FIG. 5, 11 is a mobile communication control apparatus for mobile nodes (mobile node) which is an embodiment of the present invention, 12 is a mobile communication control apparatus for general nodes (general node) which is an embodiment of the present invention, and 13 is 1 is a mobile communication control device for gateway (gateway) that is an embodiment of the present invention. Mobile node 1
1 is the address α when connected to network A
, The address β if connected to network B
have. The general node 12 has an address r. The gateway 13 has an address g. It is assumed that mobile node 11 has moved from network A to network B. Address assignment in each network is usually
It is done by the system administrator.

In the first operation example, the post-movement address acquisition means 25 of FIG. 2 acquires the post-movement address β of the mobile node 11 from, for example, the system administrator. The post-movement address acquisition means 25 immediately passes the acquired post-movement address to the movement address setting unit 26 and the movement notification transmission unit 27. The moving address setting unit 26 causes the data unit 1 to hold the correspondence between the pre-movement address α and the post-movement address β. The move notification sending unit 27 sends the correspondence between the addresses before and after the move to the gateway 13 through the line controller 4 before the move.
The packet transmitted by the movement notification transmission unit 27 is the packet 51. An example of the format of the packet 51 is shown in FIG.
It shows in (a). The timing at which the mobile node 11 transmits the packet 51 can be realized even after moving. The gateway 13 receives the packet 51 by the line control unit 4 of FIG. 3, and passes it to the received packet identification unit 35. Since the packet 51 is a packet for moving notification, it is passed to the moving notification information processing unit 36, and the moving notification information processing unit 36 takes out the pre-movement address α and the post-movement address β from the packet 51, and stores the pre-movement address in the data unit 1. The correspondence between the address α and the moved address β is stored.

The destination address of the packet 51 is
This can also be realized by setting the broadcast address to the whole network A, not to the gateway 13, and in this case, not only the gateway 13 but all the general nodes connected to the network A are the same as those before the movement of the mobile node 11. It becomes possible to receive the correspondence of the moved address. In this case, the general node 12 receives the packet 51 by the line control unit 4 of FIG. 4 and passes it to the received packet identification unit 45. Since the packet 51 is a packet for notification of movement, the received packet identification unit 45 passes the packet 51 to the address change notification information processing unit 47. The address change notification information processing unit 47 extracts the pre-movement address α and the post-movement address β from the packet 51, and stores the correspondence between the pre-movement address and the post-movement address in the data unit 1. FIG. 8 shows an example of the data format stored in the data section 1.

Next, when the general node 12 is connected to the network A and is communicating with the mobile node 11 having the address α, the mobile node 11 moves to the network B and comes to have the address β. think about. Since the general node 12 does not know the movement of the mobile node 11, the address α before the movement is set as the destination address of the packet to be transmitted to the mobile node 11. General node 12
Packet 52 is a packet transmitted from the mobile node 11 to the pre-migration address α. An example of the format of the packet 52 is shown in FIG. The packet 52 is received by the gateway 13 which is located on the path from the source general node 12 to the mobile node 11 before the movement and which is directly connected to the network to which the mobile node 11 was connected before the movement. It The gateway 13 receives the packet 52 by the line control unit 4 of FIG. 3, and passes it to the received packet identification unit 35 of the mobile address processing unit 3. Since the packet 52 is a general packet, the received packet identification unit 35 passes this to the address comparison unit 37. The address comparison unit 37 takes out the transmission destination address α of the packet 52 and compares it with the pre-movement address stored in the data unit 1 for comparison. If there is no matching pre-movement address, it is passed to the upper communication control unit 2. If there is a matching pre-movement address, the address comparing unit 37 extracts the post-movement address β corresponding to the matching pre-movement address from the data unit 1 and passes it to the address change notification transmitting unit 38. The address change notification transmission unit 38 transmits the packet 53, which is the address change notification of the destination node, to the general node 12 that is the source of the packet 52. An example of the format of the packet 53 is shown in FIG. Packet 5
Since 2 is addressed to a node that does not already exist, it is discarded inside the mobile address processing unit 3 of the gateway 13.

The general node 12 receives the packet 53 by the line controller 4 of FIG. 4, and passes it to the received packet identifier 45. Since the packet 53 is an address change notification packet, the received packet identification unit 45 passes the packet 53 to the address change notification information processing unit 47. The address change notification information processing unit 47 receives the pre-movement address α from the packet 53.
Then, the post-movement address β is taken out, and the correspondence between the pre-movement address and the post-movement address is stored in the data part 1. In this way, the general node 12 can obtain the address of the mobile node 11 after the movement. Next, a second operation example in which the general node 12 transmits a packet to the above-mentioned mobile node 11 will be described. Since the general node 12 cannot receive the arrival confirmation from the mobile node 11 which is the transmission destination of the packet 52 because the packet 52 is discarded, it is possible that the general node 12 tries to retransmit. Alternatively, it is possible to newly transmit a packet different from the packet 52. When the general node 12 again tries to transmit a packet to the mobile node 11 in this way, the general node 12 already has a correspondence between the addresses before and after the movement of the mobile node 11, so that the mobile node 11 The packet is transmitted to the address β after the movement of. The process from the general node 12 converting the destination address to transmitting will be described with reference to FIG. General node 12
At the above, the packet 54 addressed to the address α which is the pre-movement address of the mobile node 11 is passed from the upper communication control unit 2 to the address comparison unit 48. The address comparison unit 48 takes out the transmission destination address α of the packet 54 and compares it with the pre-movement address of the data unit 1 for comparison. An example of the format of the packet 54 is shown in FIG. If they do not match, they are passed to the line control unit 4 as they are. This operation example corresponds to the case where they match. If they match, the address comparison unit 4
Reference numeral 8 designates the transmission packet 54 and the marked packet conversion unit 49.
Pass to. The marked packet conversion unit 49 outputs the post-movement address β corresponding to the matched pre-movement address to the data unit 1.
From the packet 54, the destination address α of the packet 54 is rewritten to the post-movement address β, and the packet 54
The destination address α before rewriting is added as additional information, a mark is further set, and this is passed to the line control unit 4 as a packet 54 ′. An example of the format of the packet 54 'is shown in FIG. Since the destination address β of the packet 54 ′ is the address in the network in which the mobile node 11 is currently operating, it will be correctly delivered to the mobile node 11.

Next, the mobile node 11 sends packet 5 in FIG.
The process of receiving 4'and returning it to the original packet 54 before conversion will be described with reference to FIG. Mobile node 11 receives packet 5
4'is received by the line control unit 4 of FIG. 2 and passed to the received packet identification unit 28. Since the packet 54 ′ is a marked packet, the received packet identification unit 28 passes the packet 54 ′ to the marked packet restoration unit 29. The marked packet restoring unit 29 takes out the original destination address α from the additional information of the packet 54 ′, replaces the destination address β of the packet 54 ′ accordingly, and passes it to the upper communication control unit 2. As a result, the mobile node 11 can receive a packet addressed to a pre-movement address even if it moves between networks with a change in address, and the address of its own address to the application program operating on the higher-level communication control unit 2. It is possible to make continuous communication before and after moving without being aware of changes.

Next, the mobile node 11 sends a response to the packet 54 '(hereinafter simply referred to as a response packet) to the packet 5'.
A third operation example in the case of sending to the general node 12 that is the transmission source of 4'and a case in which the mobile node 11 sends a packet that is not a response (hereinafter simply referred to as a non-response packet) to the general node 12 that has been communicating before the movement is shown. In the case of a response packet, the response packet transmission unit 20 of the mobile node 11 creates a response packet as a response to the packet 54 ', and converts the response packet and the received packet 54' which is the source of the response as the transmission address before translation. The previous transmission destination address α is passed to the marked packet conversion unit 21. In the case of a non-response packet, the general node 12 of the transmission destination and the address α assigned before the movement, that is, the address α given before the movement, should be transmitted as the pre-translation transmission address The non-response packet is passed from the upper communication control unit 2 to the marked packet conversion unit 21. The marked packet converter 21 sets the address r of the general node 12 as the destination address, adds the source address α before conversion, sets the post-movement address β of itself as the source address, and sets the mark. Then, a packet 55 'is created. A format example of the packet 55 'is shown in FIG. Marked packet converter 2
1 transmits the packet 55 ′ to the general node 12 through the line controller 4. The general node 12 receives the packet 55 ′ by the line control unit 4 of FIG. 4 and passes it to the received packet identification unit 45. Since the packet 55 ′ is a marked packet, the received packet identification unit 45 passes the packet 55 ′ to the marked packet restoration unit 46. Packet restoration unit 46
Extracts the source address of the packet 55 ′, deletes the mark, replaces the pre-movement address of the mobile node of the additional information with the source address α, and restores the original packet 55 from the packet 55 ′. An example of the format of the packet 55 is shown in FIG. As a result, the application program that operates using the higher-level communication control unit 2 of the general node 12 can continue continuous communication without being aware of the movement of the communication partner.

FIG. 6 shows a case where the latest current address of the mobile node is propagated to the related node when the mobile node moves in multiple stages. In FIG. 6, the mobile node 11 uses the address m when connected to the network net1, the address m ′ when connected to the network net2, the address m ″ when connected to the network net3, and the network net4. When connected to, it has address m '''. gw1 to gw4 are mobile communication control devices for gateways according to one embodiment of the present invention.

When the mobile node 11 moves from net1 to net2, the mobile node 11 notifies the packet 61 to gw1 and gw2 directly connected to net1.
To send. The packet notifying the movement is the mobile node 11
Is transmitted from and is received by the gateways gw1 and gw2, and is set in the data unit 1 of the mobile communication control device of the gateway, which is the same as that described in the first operation example. In this operation example, the packet 61 that notifies the movement
In addition to the correspondence between the address of the mobile node before and after the move, the address before move in the previous move is included. Since this is the first move this time, 0 is set in the previous address before move. .. An example of the format of the packet 61 addressed to gw1 is shown in FIG. Note that the destination address can also be realized by the broadcast address of net1 to which gw1 is directly connected, and this is the same as when the destination address of the packet 51 for notifying the movement described in the first operation example is the broadcast address. Through the steps of, all the general nodes of net1 can hold the correspondence between the addresses before and after the movement. As a result, gw1 and gw2 hold in the data section 1 the correspondence m → m ′ between the addresses of the mobile node 11 before and after the move and the address 0 before the move in the previous move.

Next, when the mobile node 11 further moves from net2 to net3, the mobile node 11 uses net.
A packet 62 for notifying the movement is transmitted to the gateway directly connected to 2, that is, gw2 and gw3. gw
2 shows an example of the format of the packet 62 sent to
It is shown in 0 (b). Here, similarly, the destination address can also be realized by the broadcast address of net2 to which gw2 is directly connected.
It becomes possible for all general nodes at t2 to retain the correspondence between the addresses before and after the movement. gw3 is a correspondence m ′ → m ″ between addresses before and after the movement of the mobile node 11.
And the pre-movement address m in the previous movement is held. The step of transmitting a packet 62 for notifying the movement from the mobile node, and the packet 62 is received by gw3 to gw3
The steps held in the data section 1 of are the same as those already described. When the line controller 4 receives the packet 62, the gw2 passes the packet 62 to the movement notification information processor 36 via the received packet identifier 35 as in the case already described. At this point, the data unit 1 receives the packet 62, and as a result, the correspondence between the addresses of the mobile node 11 before and after the movement m
→ Holds m'and the pre-movement address 0 in the previous movement. The movement notification information processing unit 36 has a new address corresponding to the new address m ′, which has an address before movement equal to the address m ′ after movement of the mobile node 11 that is already held.
Since m ″ is received by the packet 62, the address m ′ after movement of the correspondence m → m ′ of the held addresses is changed to m ″. As a result, the correspondence of the addresses held in the data section 1 changes from m → m ′ to m →
changed to m ″. Furthermore, the movement notification information processing unit 36 of gw2 determines the correspondence m ′ → m ″ between the addresses of the mobile node 11 before and after the movement, and the address change notification transmission processing unit 38.
Pass to. Since the data unit 1 holds the pre-movement address 0 in the previous movement, the address change notification transmission processing unit 38 creates the packet 63 for the address change notification and is directly connected to the network to which gw2 itself belongs. Send to another gateway, gw1. An example of the format of the packet 63 is shown in FIG. Here, similarly, the destination address can also be realized by the broadcast address of the net1 to which the gw1 is directly connected, and similarly, all the general nodes of the net1 can hold the correspondence between the addresses before and after the movement. Will be possible. Gw1 notified of address change of mobile node
Similarly has a pre-movement address equal to the post-movement address m ′ of the mobile node 11 already held,
Since the new address correspondence m ′ → m ″ is received by the packet 63, the moved address m ′ of the address correspondence m → m ′ held in the data section 1 is changed to m ″. .. gw1 propagates when there is a gateway to propagate the address change notification to net5, but does not propagate further because there is no gateway to propagate in this operation example.

Next, when the mobile node 11 further moves from net3 to net4, the mobile node 11 uses net.
A packet 64 for notifying the movement is transmitted to the gateway directly connected to 3, ie, gw3 and gw4. gw
An example of the format of the packet 64 addressed to 3 is shown in FIG. Note that the destination address is gw here as well.
It is also possible to use the broadcast address of the network to which 3 is directly connected. As in the case already described, the gw3 notified of the address change of the mobile node is
The correspondence of the address of the mobile node held is m → m ''
To m → m ''',m' → m '' to m '→ m'''
Change to. gw3 is the address m and m ′ before the previous movement
Is held in the data section 1, but since the address change notification was propagated from the net3 to which the address m ′ belongs, ne
No address is propagated for t3. The address change notification transmission processing unit 38 of gw3 creates a packet 65 for an address change notification, and the address m belongs to n.
This packet 65 is transmitted via the line control unit 4 to the gateways directly connected to et1, that is, gw1 and gw2. In this way, the mobile node's address change notification is propagated to all associated gateways.

As a result, the correspondence of the mobile node addresses held by gw1 to gw4 when the current address of the mobile node 11 is m ″ ′ is summarized as shown in FIG. This ensures that all gateways gw1 to gw4 know the latest current address of the mobile node. In addition, a packet having any of the pre-movement addresses m, m ′, and m ″ of the mobile node as a destination address, if it reaches the network to which each address belongs, is a gateway directly connected to each network. Can notify the source node of the latest post-movement address using each address as the pre-movement address.

In FIG. 7, the gateway 13 is the mobile node 11
2 is an operation example showing a case of converting a packet addressed to a post-movement address and transferring the packet when receiving a packet addressed to the pre-movement address.

Packet 71 and packet 72 in FIG.
Are packet 51 and packet 5 in FIG. 5, respectively.
It is the same as 2. The gateway 13 uses packet 7
The flow until receiving 2 is the same as in the first operation example. The process after the gateway 13 receives the packet 72 will be described with reference to FIG. Gateway 13
Receives the packet 72 by the line control unit 4 of FIG. 3 and passes it to the received packet identification unit 35 of the mobile address processing unit 3. Since the packet 72 is a general packet, the received packet identification unit passes the packet 72 to the address comparison unit 37. The address comparison unit 37 takes out the destination address of the packet 72 and compares it with the address before movement stored in the data unit 1 to see if it matches. If there is no matching pre-movement address, it is passed to the upper communication control unit 2. If there is a matching pre-movement address, the post-movement address corresponding to the matching pre-movement address is extracted, and the post-movement address and the packet 72 are passed to the marked packet conversion unit 39 in this operation example. The marked packet conversion unit 39 rewrites the destination address of the packet 72 to the post-movement address passed from the address comparison unit 37, and the packet 72
The destination address before rewriting is added as additional information, a mark is further set, and the packet 72 ′ is passed to the line control unit 4. An example of the format of packet 72 'is shown in FIG.
Shown in 1. Since the destination address of the packet 72 'is the address in the network where the mobile node 11 is currently operating, it will be correctly delivered to the mobile node 11. As a result, the packet sent to the address before the movement of the mobile node 11 is correctly received by the mobile node 11 without being lost.

In each of the above operation examples, the data unit 1 of the mobile communication control device is realized by the non-volatile storage means so that the communication with the mobile node can be performed even after power-off of the node or gateway or system reset occurs. You can do it right. Further, in the case of a general node, even when the data unit 1 is realized by a volatile memory, the node that holds the latest address of the mobile node when communication with the mobile node is started after the power is cut off or the like. By obtaining the latest address from the general node, it becomes possible to correctly communicate with the mobile node after the power failure or system reset of the general node occurs and without the need to repeat the move notification from the gateway. An example of this operation will be described. As described in the example shown in FIG. 6, it is assumed that the mobile node sequentially moves from net1 to net4 in multiple stages. At this time, the mobile communication control device of the general node, which has communicated with the mobile node on net4 at least once, stores in the data portion 1 the correspondence between the address of the mobile node before and after the move of m → m ′ ″. .. If this is lost due to power failure, etc., send a packet to m again,
Instead of reaching m '''after receiving the movement notification from the gateways gw1, gw2, gw3 sequentially from there,
Make sure that one or more specific nodes on the network always obtain the latest address information when the mobile node moves, so that when the mobile node starts communication with the general node mobile node, the latest By inquiring about the address to the specific node holding the latest address information, it becomes possible to communicate with the mobile node without going through the process of notification of movement from a plurality of gateways.

In the third operation example described with reference to FIG. 5, when the mobile node transmits a non-response packet to the general node with which the mobile node was communicating before moving, the source address before conversion is controlled by the upper communication. Although obtained from the section 2, when a communication connection is set up between the application program of the mobile node and the general node, the mobile communication control device of the mobile node identifies the set communication connection and its own node at that time. Is stored in the data unit 1, and instead of the source address before conversion in the third operation example, the connection identifier is obtained from the upper communication control unit, and the address corresponding to the connection identifier is obtained. It can also be realized by obtaining the address from the data section 1 and using that address as the transmission address before conversion.

Further, as described in the first operation example of FIG. 5 and the operation example of FIG. 6, the packet for the mobile node movement notification does not have only the gateway as the destination address, but the gateway exists. This can also be realized by using a broadcast address for the entire network. In that case, when all the general nodes directly connected to the network correspond to the addresses before and after the movement of the mobile node, the time when the mobile node moves. It will be received and held by. As a result, the general node directly sends the packet to the address after the move without the procedure of sending the packet to the address before the move of the mobile node and receiving the packet of the move notification from the gateway. Good communication is possible.

If the number of correspondences between the addresses before and after the movement that the general node can hold is limited due to the limitation of the storage device, etc., the number of correspondences between the addresses before and after the movement to be held is More effective information is provided by providing means for deleting from the data section 1 the correspondence between the address before the movement and the address after the movement, which is held for a longest time and is not referred to by the address comparison section 43 when the number exceeds a certain number. Can be stored in the data section.

[0047]

As described above, according to the present invention, when a node as a communication partner moves between networks, a node that wants to transmit a packet to an address before the movement has a function before and after the movement of the mobile node. By keeping the correspondence of addresses, converting the packet to the address after moving and transmitting it, not only can the packet be correctly sent to the target mobile node, but the packet addressed to the mobile node can also pass through an extra route. Instead, it will reach the mobile node.

Further, the gateway directly connected to the network to which the pre-movement address of the mobile node belongs holds the correspondence between the pre-movement address and the post-movement address of the mobile node, and the packet addressed to the pre-movement address of the mobile node is said gateway. When it tries to pass the packet, it detects that the receiving node does not already exist, and notifies the node that sent the packet to the address before the movement of the mobile node, the movement of the mobile node and the addresses before and after the movement. be able to.

Furthermore, the mobile node itself notifies the gateway directly connected to the network to which the pre-movement address belongs or all the nodes of the correspondence between the pre-movement address and the post-movement address so that the information that the mobile node has moved can be promptly displayed. Can be propagated.

Further, according to the present invention, a node which intends to transmit a packet to the moved node moves the packet addressed to the address before the movement of the mobile node based on the correspondence between the addresses before and after the movement of the mobile node. The packet is converted to a marked packet addressed to a later address, the destination address before conversion is added to the marked packet and transmitted, and the mobile node that receives the marked packet changes the marked packet before conversion. When restoring and sending the packet, the packet from the address before movement is converted to the packet with the address from the mark after movement, and the source address before conversion is added to the marked packet before transmission. Then, the receiving node of the packet communicates with the mobile node by restoring the unconverted packet from the marked packet. Partner node to become identifiable that the address of the mobile node is a packet from the mobile node be changed by the movement, it is possible to perform continuous communication before and after the move node moving.

Further, according to the present invention, the mobile node sets the correspondence between the addresses of the mobile node itself before and after the move and the address before the move in the previous move if it is not the first move before the move of the mobile node. After propagating to the gateway directly connected to the network to which the address belongs, and if the gateway already holds the address set, the post-movement address of the address set held by the pre-movement address of the received address set When the match is found, the post-movement address of the set of addresses held is replaced with the post-movement address of the set of received addresses, and the previous pre-movement address of the set of addresses holding the correspondence of the replaced addresses. By sending to the gateway that is directly connected to the network to which the Mobile node is propagated quickly even if to repeat the movement in multiple stages, associated node can know the latest current address of the mobile node.

Furthermore, the mobile node that repeats the movement in multiple stages notifies all the nodes directly connected to the network to which the pre-movement address belongs of the addresses before and after the movement and the previous pre-movement address. , Information that the mobile node has moved can be quickly propagated.

Further, the gateway, which propagates the correspondence between the addresses of the mobile node before and after the movement, transfers the correspondence between the addresses of the mobile node before and after the movement to all the nodes directly connected to the network to which the address before the movement belongs. By notifying the mobile node, the node that has never communicated with the mobile node can know the post-movement address of the mobile node. As a result, the node that is directly connected to the network through which the mobile node moves repeatedly
Without trying to send a packet to the address before moving,
Packets can be sent to the post-movement address from the first communication with the mobile node.

[Brief description of drawings]

FIG. 1 is a block diagram showing a schematic configuration of a mobile communication control device of the present invention.

FIG. 2 is a block diagram showing a detailed configuration of a mobile communication control device for mobile node of the present invention.

FIG. 3 is a block diagram showing a detailed configuration of a mobile communication control device for gateway of the present invention.

FIG. 4 is a block diagram showing a detailed configuration of a mobile communication control device for a general node according to the present invention.

FIG. 5 is a diagram for explaining first to third operation examples of the present invention.

FIG. 6 is a diagram for explaining an operation example in which movement is performed in multiple stages according to the present invention.

FIG. 7 is a diagram for explaining an operation example when the gateway converts and transfers a packet according to the present invention.

FIG. 8 is a data configuration diagram of the data section 1.

FIG. 9 is a format diagram for explaining first to third operation examples of the present invention.

FIG. 10 is a format diagram for explaining an operation example in which movement is performed in multiple stages according to the present invention.

FIG. 11 is a format diagram for explaining an operation example when the gateway performs packet conversion and transfer according to the present invention.

FIG. 12 is a conceptual diagram of conventional communication when a node moves.

FIG. 13 is a diagram summarizing the result of the correspondence between addresses before and after the movement of a mobile node being propagated to related gateways.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 data section 2 upper communication control section 3 mobile address processing section 4 line control section 11 mobile communication control apparatus for mobile node 12 mobile communication control apparatus for general node 13 mobile communication control apparatus for gateway 20 response packet transmission section 21 marked packet Conversion unit 25 Post-movement address acquisition unit 26 Movement address setting unit 27 Movement notification transmission unit 28 Reception packet identification unit 29 Marked packet restoration unit 35 Reception packet identification unit 36 Movement notification information processing unit 37 Address comparison unit 38 Address change notification transmission unit 39 Marked packet conversion unit 45 Received packet identification unit 46 Marked packet restoration unit 47 Address change notification information processing unit 48 Address comparison unit 49 Marked packet conversion unit 51 Mobile node movement notification packet 52 Mobile node ad Packet 53 to the mobile node to notify the mobile node 54 'to the mobile node marked packet addressed to the mobile node 55' to the mobile node marked packet 61 to the mobile node to propagate the initial movement 62 mobile node Is a packet that propagates the second movement 63 A packet that the gateway propagates when moving the second time 64 A packet that the mobile node propagates a third movement 65 A packet that the gateway propagates when the third movement 71 Moves issued by the mobile node Node move notification packet 72 Packet addressed to pre-movement address 72 'Packet marked for mobile node issued by gateway 91 Destination address 92 Source address 93 Data 94 Mobile node pre-movement address 95 Mobile node post-movement address 96 Ma Click 97 additional information 98 message type 101 address before the move in the pre-movement address 102 the movement of the moving after the address 103 previous

Claims (8)

[Claims] 1. When the first node as a communication partner moves between networks, the second node attempts to transmit a packet to the address of the first node before the movement, the first node Receiving the address correspondence from the node holding the correspondence of the addresses before and after the movement, holding the correspondence of the addresses, and the first correspondence before the movement based on the correspondence of the addresses. The steps of converting a packet addressed to the address of the node into a packet addressed to the moved address and sending the converted packet are directly connected to the network to which the pre-movement address of the first node belongs. Receiving the address correspondence from the node holding the correspondence between the addresses before and after the movement of the first node by the gateway, Mobile node control method, when receiving a packet addressed to an address before the node moves, the step of transmitting the address correspondence to the source node of the packet, that is, the second node. .. 2. The second node, which attempts to send a packet to the first node that has moved, uses the correspondence between the addresses of the first node before and after the movement of the first node before the movement of the first node. Of the packet addressed to the address of FIG. 2 to a marked packet addressed to the moved address, adding a destination address before conversion to the marked packet, and sending the marked packet. When the first node receives the marked packet, the first node restores the packet before conversion from the marked packet, and the destination address of the restored packet is A step of returning to the destination address before conversion attached to the marked packet, wherein the first node causes the first node to When a packet is to be transmitted to the second node as a response to the marked packet, the untranslated destination address in the received packet is added as the untranslated source address and is also sent out as a marked packet. If the first node performs the process and tries to transmit a packet to the node with which the first node has communicated before the first node moves, the first node holds the packet before the move. Of the correspondence of the address after movement, the partner node is the first
While converting the packet whose source address is the address used as the address of the node of 1 to the packet originating from the address after movement, adding the source address before translation and sending it as a marked packet, When the second node, which is the destination of the marked packet, receives the marked packet, the second node restores the packet before conversion from the marked packet, and And a step of returning the source address of the packet to the source address before conversion added to the marked packet. 3. The step of retaining all the pre-movement addresses and the current addresses of the first node itself by the first node which is the mobile node, and the correspondence between the pre-movement address and the post-movement address of the first node. And if it is not the first move, a set of the before-movement address in the previous move and a step of transmitting to the gateway directly connected to the network to which the before-movement address of the first node belongs, by the gateway, Receiving a set of addresses, and holding the set of addresses when the set of addresses having a pre-movement address that matches the pre-movement address among the received correspondences of pre-movement and post-movement addresses is not held Step, and if the address set is already held, the address before movement of the received address set is after the movement of the held address set When the addresses match, the step of replacing the post-movement address of the retained address set with the post-movement address of the received address set, and the correspondence of the post-replacement address to the set to which the correspondence of the replaced address belongs And a step of transmitting to a gateway directly connected to the network to which the previous pre-movement address in the above belongs. 4. The mobile communication control system according to claim 3,
The first node performs a step of transmitting the correspondence between the addresses before and after the movement of the first node itself to all the nodes directly connected to the network to which the address before movement belongs, and the node which receives the correspondence. Therefore, if the corresponding post-movement address of the address already held by the node matches the corresponding pre-movement address of the received address, the corresponding post-movement address of the held address is received A mobile communication control method characterized by performing the step of replacing the corresponding post-movement address with. 5. The mobile communication control method according to claim 3,
By the gateway, the correspondence of the address after replacement,
The step of transmitting to all the nodes directly connected to the network to which the previous pre-movement address to which the correspondence of the replaced address belongs belongs is performed, and the node which receives the correspondence already holds the correspondence. If the post-movement address corresponding to the address matches the pre-movement address corresponding to the received address, the step of replacing the post-movement address corresponding to the held address with the post-movement address corresponding to the received address is performed. A mobile communication control method characterized by the above. 6. Receiving means for receiving address correspondence from a node holding correspondence between addresses of a mobile node before and after movement, holding means for holding correspondence of the addresses, and correspondence for the addresses A mobile communication control unit for a general node, which includes a conversion means for converting a packet addressed to the address before the movement of the mobile node into a packet addressed to the address after the movement, and a transmission means for transmitting the converted packet. And a receiving means for receiving the correspondence between the addresses of the mobile node before and after the movement, a holding means for holding the correspondence, and a source of the packet when the packet addressed to the address before the movement of the mobile node is received. A mobile communication control unit for a gateway including a transmission means for transmitting a correspondence between addresses before and after movement of a mobile node to a node A mobile communication control device characterized by the above. 7. A conversion means for converting a packet addressed to the address before the movement of the mobile node into a marked packet addressed to the address after the movement of the mobile node based on the correspondence between the addresses before and after the movement of the mobile node, and Addition means for adding the destination address before conversion to the marked packet, sending means for sending the marked packet, and the source address converted from the pre-movement address to the post-movement address by the mobile node of the communication partner When the marked packet with the source address of is received, the restoring means for restoring the unconverted packet from the marked packet, and the source address of the restored packet is added to the marked packet. A mobile communication control unit for a general node, which includes means for returning to a source address before translation, When receiving a marked packet with the destination address translated from the pre-movement address to the post-movement address by the correspondent node and the destination address before translation is added, the packet before translation is restored from the marked packet Restoring means for restoring the destination address of the restored packet to the destination address before conversion added to the marked packet, and a packet to be transmitted to the source as a response of the marked packet In this case, the destination address before conversion in the received packet is used as the source address, and when the packet is to be transmitted to the node with which the mobile node had been communicating before the movement, the mobile node itself holds the packet. Of the correspondence between the addresses before and after the move, the partner node uses it as the address of the mobile node. Translating means for translating a packet whose source address is the address of the mobile node into a marked packet originating from the post-movement address; adding means for adding the source address before translation to the marked packet; A mobile communication control device comprising: a mobile communication control unit for a mobile node, which comprises a sending means for sending an attached packet. 8. Receiving means for receiving a pair of correspondence between addresses of a mobile node before and after a move and a pre-movement address in the previous move if the move of the mobile node is not the first move, and before the received move. And holding means for holding the correspondence of the address when the pair of addresses having the pre-movement address that matches the pre-movement address among the correspondence of the post-movement address is not held, If the pre-movement address of the received address set matches the post-movement address of the held address set, the post-movement address of the held address set of the received address set The replacement unit that replaces the post-movement address and the direct connection to the network to which the previous pre-movement address of the set of addresses that retain the correspondence of the post-movement address belong. Before the move in the previous move, the mobile communication control unit for the gateway, which has a transmitting means for sending to the connected gateway, and the correspondence between the addresses before and after the move of the mobile node and the first move unless it is the first move For a mobile node comprising holding means for holding a pair with an address, and transmitting means for transmitting the pair of addresses to a gateway directly connected to a network to which the previous pre-movement address in the address pair belongs A mobile communication control device comprising a mobile communication control unit.