JP2004356679A - Ad hoc network address providing system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enable communication including the IPv4 by automatically constituting an ad hoc network. <P>SOLUTION: An IP address providing system is disclosed which is constituted in such a manner that terminals taking part in the ad hoc network generate IPv6 addresses on the basis of IPv6 link local addresses to constitute a network, IPv4 addresses are made to correspond to the IPv6 addresses of the network to thereby automatically constitute the network for the IPv4 addresses. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to addresses in ad hoc networks.
[0002]
[Prior art]
In the IPv4 protocol, when a DHCP server exists in a wired LAN and a wireless LAN, an IP address can be assigned to a terminal on a network from the DHCP server (for example, see Non-Patent Document 1). However, in the ad hoc network, it was necessary to set individually. In the IPv6 protocol, a wired LAN and a wireless LAN can be assigned from a router and a DHCP server, and an ad hoc network can have a unique link-local address (when a terminal has a MAC address) (for example, see Non-Patent Document). 2).
[0003]
[Non-patent document 1]
R. Droms, RFC1541 Dynamic Host Configuration Protocol [online], October 1993, The Internet Engineering Task Force, [Retrieved February 7, 2003], Internet <URL: http: // www. ief. org / rfc / rfc1541. txt? number = 1541>
[Non-patent document 2]
T. Narten, E .; Nordmark, W.C. Simpson, RFC2641 Neighbor Discovery for IP Version 6 (IPv6), [online], December 1998, The Internet Engineering Task Force, [Search on February 7, 2003: w. ief. org / rfc / rfc2461. txt? number = 2461>
[0004]
[Problems to be solved by the invention]
The problem is to automatically assign an IPv4 address to a terminal on an ad hoc network that proactively exchanges route information, and to configure an IPv4 or a mixed IPv4 / IPv6 network.
[0005]
An object of the present invention is to automatically configure an ad hoc network and enable communication including IPv4.
[0006]
[Means for Solving the Problems]
In the IP address assignment method according to the present invention, a terminal participating in an ad hoc network creates an IPv6 address based on an IPv6 link local address to form a network, associates an IPv4 address with the IPv6 address of the network, and automatically creates an IPv4 address. Configure a network with an IPv4 address.
[0007]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0008]
FIG. 1 is a configuration diagram of a system showing the equipment and functions of the present invention. It is composed of a terminal A (1), a terminal B (2), a terminal C (3), and a terminal D (4) which newly join the ad hoc network, and communicates with a wireless LAN. The newly added terminal D (4) establishes IPv6 communication with the terminals A (1), B (2) and C (3) according to the IPv6 routing protocol (401). The terminals A (1), B (2) and C (3) which have already formed the ad hoc network have the IPv6-IPv4 address correspondence table (11, 21, 31), and the terminal D (4) receives this ( 201), an IPv4 address is automatically assigned by acquiring a free number in a predetermined IPv4 address range and declaring it to another terminal (402). The correspondence table acquisition and the IPv4 address declaration include all methods.
[0009]
FIG. 2 is a diagram showing an operation of connecting one terminal B (2) to a terminal A (1) having one address correspondence table, and FIG. 7 shows a communication procedure thereof. After the connection procedure based on IPv6, the terminal B (2) requests the address correspondence table (12) from the terminal A (1) using the IPv6 protocol (211). The terminal A (1) notifies the terminal B (2) of the address correspondence table (12) in response to the request (121). The terminal B (2) selects an unused IPv4 address from the address correspondence table (12), creates a registered address correspondence table (23), and notifies the terminal A (1) of the address (231).
[0010]
FIG. 3 is a diagram illustrating an operation in which the terminal C (3) joins the ad hoc network by connecting to the terminal A (1) with respect to the networks of the terminals A (1) and B (2). The communication procedure. After the connection procedure based on IPv6, the terminal C (3) requests the address correspondence table (23) from the terminal B (2) using the IPv6 protocol (311). The terminal A (1) notifies the address correspondence table (13) to the terminal C (3) in response to the request (131). The terminal C (3) selects an unused IPv4 address from the address correspondence table (13), creates a registered address correspondence table (34), and notifies the terminal A (1) of the address (341). The terminal A (1) updates its own address correspondence table (14) with the received address correspondence table (34). The terminal A (1) notifies this to the terminal B (2) (141), and the terminals A (1), B (2) and C (3) can share the address correspondence table.
[0011]
FIG. 4 is a diagram showing an operation in which the terminal D (4) joins the ad hoc network by connecting to the terminal B (2) with respect to the networks of the terminals A (1), B (2) and C (3). FIG. 9 shows the communication procedure. After the connection procedure based on IPv6, the terminal D (4) requests the address correspondence table (24) from the terminal B (2) according to the IPv6 protocol (411). The terminal B (2) notifies the address correspondence table (24) to the terminal D (4) in response to the request (241). The terminal D (4) selects an unused IPv4 address from the address correspondence table (24), creates a registered address correspondence table 45, and notifies the terminal B (2) (451). The terminal B (2) updates its own address correspondence table (25) with the received address correspondence table 45. The terminal B (2) notifies this to the terminal A (1) (251). The terminal A (1) updates its own address correspondence table (15) and notifies the terminal C (3) (151), and A (1), B (2), C (3), D (4). Of terminals can share the address correspondence table.
[0012]
FIG. 5 is a diagram showing a case where address duplication occurs in the case of FIG. 4, and FIGS. 10 and 11 show the communication procedure. At the time point when the terminal B (2) notifies the terminal D (4) of the address correspondence table (231), the address correspondence table (14) for the terminal C (3) participation from the terminal A (1) has not been received, At the time when the terminal D (4) creates the address correspondence table and notifies the terminal B (2) (442), the address correspondence table (14) has been received. Terminal B (2) is newly based on the address correspondence table of terminals A (1), B (2) and C (3) and the address correspondence table of terminals A (1), B (2) and D (4). The updated address correspondence table (28) is updated. Here, the consistency is determined (291), and if there is no overlap, an address correspondence table of terminals A (1), B (2), C (3) and D (4) is created. If there is an IPv4 address overlap between C (3) and D (4), the address is reselected to one (in this case, terminal D (4)) according to a predetermined rule (eg, the size of the IPv6 address). (292). The terminal D (4) selects the IPv4 address again, updates the address correspondence table (44), and notifies the terminal B (2) of the address correspondence table (442). If the terminal B (2) can determine that there is no duplication, it notifies another terminal of a new address correspondence table as in FIG. 4 (281, 282, 181).
[0013]
FIG. 6 is an example of an address correspondence table, which includes correspondence between IPv6 addresses and IPv4 addresses and a list of target IPv4 addresses.
[0014]
FIG. 12 is a diagram illustrating an example in which one terminal leaves the ad hoc network, and FIG. 13 illustrates a communication procedure thereof. If the terminal D (4) stops or moves out of the communication range of the ad hoc network and the terminal B (2) cannot receive the message from the terminal D (4) (202), immediately or in accordance with a prescribed rule After the time according to (2), the terminal is contacted to another terminal (242, 243). When it is determined that the message of the terminal D (4) cannot be confirmed from the other terminal (191, 291), the terminal D (4) is deleted from the address correspondence table and notified to the other terminal (232, 233). If any of the other terminals can confirm the message of D (4), the address correspondence table is not changed.
[0015]
FIG. 14 is a diagram illustrating a case where two ad hoc networks having the same target IPv4 address are connected, the address correspondence table is updated, and if necessary, addresses are reassigned. FIGS. It is. Network X (100) including terminal A (1) and terminal C (3) and network Y (200) including terminal B (2) and terminal D (4) share a communication range. The terminal B (2) starts communication (101). A terminal notifies the other terminal of an address correspondence table according to a predetermined rule (here, terminal A (1) notifies terminal B (2) of address correspondence table (17)) (171). The address correspondence table (27) held by the terminal B (2) is updated, the consistency is confirmed (293), and the priority of the duplicate address is determined (here, C (3) and D (4) Duplicate, C (3) has priority), and terminal B (2) issues a change instruction (294) to D (4). The terminal D (4) re-creates the address correspondence table (47), and the terminal D (4) notifies the terminal B (2) of the address correspondence table (47) (472) and creates the address correspondence table (47). The terminal A (1) and the other terminal of the network Y (200) are notified of the address correspondence table (28) (281, 282). Hereinafter, the same processing is performed until the duplication disappears.
[0016]
Here, in order to realize the above communication procedure, a process embodied by a CPU executing a program in each terminal will be described with reference to FIGS.
[0017]
FIG. 17 is a flowchart showing a process at the time of startup such as system startup. After a timer interrupt (51), the system enters a state of waiting for receiving IPv6 route information (52). When route information is received, the routing table is written from the route information (53). ) Is performed, and if the IPv4 process has not been started, the IPv4 address acquisition process is started (55), and the process returns to the waiting state for receiving IPv6 route information (52). In the timer interrupt routine (51), transmission of IPv6 route information (511) and timer setting (512) are performed.
[0018]
FIG. 18 is a flowchart showing the start of the IPv4 address acquisition process (55). After transmitting the address correspondence table acquisition request (551) and receiving the request in the address correspondence table reception wait (552), the IPv4 address is acquired based on the correspondence table. The writing (553) is performed, the updated address correspondence table is transmitted (554), and the IPv4 ad hoc network process activation (6) processing is performed. Thereafter, a packet reception wait state (555) is entered, and after reception, packet analysis (556) is performed to determine three types of requests: address correspondence table transmission, address update request, and address correspondence table transmission request. In the case of transmitting the address correspondence table, the address correspondence table is updated (557). If there is a problem with the consistency, the address update request is transmitted (558), and the process returns to the packet reception wait (555). In the case of an address update request, the address correspondence table is re-created (561), the updated address correspondence table is transmitted (562), and since the own IPv4 address has been changed, the IPv4 ad hoc network process activation (6) processing is performed. Then, the process returns to waiting for packet reception (555). In the case of the address correspondence table transmission request, the address correspondence table is transmitted (571), and the process returns to the packet reception waiting (555).
[0019]
FIG. 19 is a flowchart showing the start of the IPv4 ad hoc network process (6). After the timer interrupt (61), the process enters a waiting state for receiving IPv4 route information (62). When the IPv4 route information is received, the routing table is written from the route information (63). ), And returns to the waiting state for receiving IPv4 route information (62). In the timer interrupt routine (61), transmission of IPv4 route information (611) and timer setting (612) are performed.
[0020]
As described above, the present invention has been specifically described. However, the present invention is not limited to the above embodiments.
[0021]
【The invention's effect】
It enables automatic assignment, addition, deletion, and reassignment of IPv4 addresses in an ad hoc network that does not have address provision equipment such as a DHCP server. Also, it can support both IPv6 and IPv4 applications.
[Brief description of the drawings]
FIG. 1 Overview.
FIG. 2 shows an example of an address assignment operation when a terminal is added (one unit + 1).
FIG. 3 is an example of an address assignment operation when adding a terminal (2 + 1).
FIG. 4 shows an example of address assignment operation when adding a terminal (3 + 1).
FIG. 5 is an example of an address assignment operation when a terminal is added (address duplication).
FIG. 6 is an example of an address correspondence table.
FIG. 7 is a communication procedure of FIG. 2;
FIG. 8 is a communication procedure of FIG. 3;
FIG. 9 is a communication procedure of FIG. 4;
FIG. 10 is a communication procedure of FIG. 5;
FIG. 11 shows a second communication procedure of FIG.
FIG. 12 shows an example of terminal disconnection and correspondence table update.
FIG. 13 is a communication procedure of FIG.
FIG. 14 shows an example of connection of an ad hoc network and reallocation of addresses.
FIG. 15 is a communication procedure of FIG. 14;
FIG. 16 shows a second communication procedure of FIG.
FIG. 17 is a flowchart of a process at the time of activation.
FIG. 18 is a flowchart of starting an IPv4 address acquisition process.
FIG. 19 is a flowchart of starting an IPv4 ad hoc network process.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Terminal (A), 2 ... Terminal (B), 3 ... Terminal (C), 4 ... Terminal (D), 11 ... Address correspondence table, 21 ... Address correspondence table, 31 ... Address correspondence table, 41 ... Address correspondence Table, 201: Correspondence table acquisition, 401: IPv6 routing protocol, 402: IPv4 address declaration.

Claims (3)

A network address assignment method for assigning, adding, deleting, and reassigning IPv4 addresses in an ad hoc network. 2. The network address assignment method according to claim 1, wherein the network address is automatically assigned only to the client terminal. 2. The address assignment method according to claim 1, wherein an IPv4 address is assigned based on the IPv6 address, and the IPv6 address is compatible with both IPv6 and IPv4 networks.

Images