JP2005267061A - Communication system and address list acquisition method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain addresses of all terminals of other groups while all terminals have a small data amount.
A peer Y1 that has acquired an address of a peer X1 transmits address range information [null, null] and an address list L2 of a group G2 to the peer X1, and the peer X1 newly performs an address list transfer process. The generated address range information and the address list L2 are transmitted to the peers X2 and X3. On the other hand, the peer X1 transmits the address list L1 of the group G1 to the peer Y1 and the address range information [null, null] to the peer Y1, and the peer Y1 newly generates the address range generated by the address list transfer process. Information and address list L1 are transmitted to peer Y2.
[Selection] Figure 4

Description

  The present invention relates to a communication system composed of a first group and a second group, and more particularly to a technique in which all terminals acquire the addresses of all terminals belonging to the other group.

  2. Description of the Related Art In recent years, a pure peer-to-peer network system that can share various data within a network without installing a server dedicated machine has attracted attention. This pure peer-to-peer network system can share data such as files owned by each terminal within a group configured between a plurality of terminals communicably connected via an Internet line or a LAN line. System.

  In a pure peer-to-peer network system, each terminal constituting a group needs to know the communication addresses of all terminals belonging to the group. Therefore, when a certain terminal is added to the group, the address of the terminal must be notified to each personal computer constituting the group, and the address of each terminal constituting the group must be notified to the added terminal.

  Nutella (gnutella) is widely known as software for realizing a pure peer-to-peer network system. When a new terminal is added, the added terminal broadcasts a PING message to each terminal in the group. On the other hand, each terminal receiving this message responds with a PONG message. As a result, the above-described address notification is performed. The broadcast PING message is set with a TTL (time to live) value that is decremented by 1 every time it passes through the terminal, and is transferred by each terminal within the group until TTL = 1.

  Specifically, the IP address and port number of the transmission source are included in the PING message, and the IP address and port number of each terminal that has responded to the PONG message are included in the PONG message. Therefore, the terminal added to the group can know the address of each terminal in the system, and each terminal in the group can also know the address of the added terminal.

  FIG. 8 is a diagram illustrating the flow of a PING message and a PONG message that are transmitted when a terminal P1 is newly added to a group of terminals P2 to P8. FIG. 8A illustrates the flow of a PING message. (B) shows the flow of the PONG message.

  In the case of FIG. 8, the PING message M1 transmitted from the terminal P1 and set to TTL = 3 is transmitted to the adjacent terminal P2, is set to TTL = 2 by the terminal P2, and is transferred to the adjacent terminals P3 and P4. . The PING message M1 received by the terminal P3 is set to TTL = 1 and transferred to the terminals P5 and P6 adjacent to the terminal P3. The PING message 1 received by the terminal P4 is set to TTL = 1 and transferred to the terminals P6 and P7 adjacent to the terminal P4. From the above, the terminals P2 to P7 know the address of the terminal P1.

  On the other hand, the terminals P5 to P7 that have received the PING message M1 transmit PONG messages M5 to M7 to the adjacent terminals P3 and P4. The terminal P3 transmits its own PONG message M3 to the adjacent terminal P2, and transfers the PONG messages M5 and M6 transmitted from the terminals P5 and P6 to the terminal P2. Also, the terminal P4 transmits its own PONG message M4 to the terminal P2, and transfers the PONG messages M6 and M7 transmitted from the terminals P6 and P7 to the terminal P2. Furthermore, in addition to transmitting its own PONG message M2 to the terminal P1, the terminal P2 transfers the PONG messages M3, M5, M6 transmitted from the terminal P3 to the terminal P1 and also transmits the PONG transmitted from the terminal P4. The messages M4, M6 and M7 are transferred to the terminal P1. Thereby, the terminal P1 knows the addresses of the terminals P2 to P5.

  However, according to the above method, since the transfer of the PING message is terminated when TTL = 1, the PING message may not be transmitted to all terminals constituting the group. For example, the terminal P8 shown in FIG. 8A cannot receive the PING message because TTL = 1 in the terminal P5. Since the terminal that could not receive the PING message cannot know the address of the newly added terminal and does not respond by PONG, the newly added terminal receives the PING message. The problem arises that the address of the terminal that could not be obtained cannot be known.

  Also, since the PING message is broadcast, as shown in the terminal P6 in FIG. 8A, the same PING message is repeatedly transmitted to one terminal, and the data flowing in the group increases. There's a problem. Furthermore, each terminal transmits a PONG message every time it receives a PING message, and also transfers the received PONG message, so that there is a problem that the number of PONG messages flowing in the group becomes enormous. For example, the terminal P3 shown in FIG. 8B transmits three PONG messages M3, M5, and M6 to the terminal P2, and the terminal P4 also transmits three PONG messages M4, M6, and M7 to the terminal P2. ing.

  Furthermore, there is a problem that a huge number of PONG messages are transmitted to a terminal adjacent to the transmission source of the PING message. For example, the terminal P2 shown in FIG. 8 (b) receives the PONG messages M3, M5, and M6 from the terminal P3 and the PONGU messages M4, M6, and M7 from the terminal P4 and receives the PONG The number of messages is huge.

  The object of the present invention is to add another group of terminals consisting of one or more terminals to a group consisting of one or more terminals, while all the terminals are in other groups while having a small amount of data. It is to provide a communication system and an address list acquisition method capable of acquiring addresses of all terminals.

  The communication system according to the present invention includes a first group composed of one or more terminals, and a second group composed of one or more terminals communicably connected to the first group. Each terminal is provided with a storage means for storing an address list in which addresses of all the terminals in the same group are described, each of which is provided with an address consisting of a numerical number unique to each terminal, and each terminal has the other group A first terminal belonging to the first group generates address range information in which the first and second data are null, and the generated address range information; The address list of the first group is transmitted to the second terminal, and the second terminal generates address range information in which the first and second data are null and generates The address range information and the address list of the second group are transmitted to the first terminal, and each terminal including the first and second terminals receives the first data of the received address range information as null. In this case, address range information having null as the first data and self address as the second data is generated, and the generated address range information and the received address list are assigned addresses smaller than the self address within the same group. If the first data of the address range information transmitted to and received by one terminal is not null, the first data and the second data of the address range information from which the first data is received are self addresses. Range information is generated, and the generated address range information and the received address list are larger than the first data in the same group, and are self-addressed. If the second data of the received address range information is null when it is transmitted to one terminal having an address smaller than the address, address range information with the first data as its own address and the second data as null The generated address range information and the received address list are transmitted to one terminal having an address larger than the self address in the same group, and the second data of the received address range information is null. If not, generate address range information in which the first data is the self address and the second data is the second data of the received address range information, and the generated address range information and the received address list are in the same group And transmitting to one terminal having an address larger than the self address and smaller than the second data. Features.

  In addition, when each terminal generates address range information in which the first data is null and the second data is a self address, the address generated in the terminal having an intermediate address between the upper limit address and the self address of the same group When the range information and the received address list are transmitted and address range information is generated with the first data as the self address and the second data as the upper limit address, the intermediate between the self address and the upper limit address of the same group When the address range information generated to the terminal having the address and the received address list are transmitted and the address range information in which both the first and second data are not null is generated, the first data and the second data The generated address range information and the received address list can be transmitted to a terminal having an intermediate address Masui.

  The address is preferably composed of an IP address and a port number.

  The address list acquisition method according to the present invention includes a first group composed of one or more terminals, and a second group composed of one or more terminals communicably connected to the first group. Each terminal is provided with a storage means for storing an address list in which addresses of all terminals in the same group are described, each of which is provided with an address consisting of a number unique to each terminal consisting of a numerical value. An address list acquisition method for acquiring an address list of a group, wherein the first terminal belonging to the first group generates address range information in which the first and second data are null, and the generated address The range information and the address list of the first group are transmitted to the second terminal, and the second terminal has an address range in which the first and second data are null. Information is generated, the generated address range information and the second group address list are transmitted to the first terminal, and each terminal including the first and second terminals receives the received address range information. When the first data is null, address range information is generated with the first data as null and the second data as a self address, and the generated address range information and the received address list are self-addressed within the same group. When the first data of the address range information transmitted to one terminal having an address smaller than the address is not null, the first data and the second data of the address range information received from the first data Address range information having a self address as the first data, and the generated address range information and the received address list in the same group. If the second data of the received address range information is null, the first data is the self address and the second data is null. The address range information is generated, and the generated address range information and the received address list are transmitted to one terminal having an address larger than the self address in the same group, and the received address range information If the data of 2 is not null, address range information is generated with the first data as the self address and the second data as the second data of the address range information received, and the generated address range information and the received address A list having a larger address than the self address and smaller than the second data in the same group. It transmits to a terminal, It is characterized by the above-mentioned.

  According to the first and fourth aspects of the invention, the first terminal belonging to the first group generates address range information in which both the first and second data are null, and the first terminal stores the address range information. Along with the address list of the first group, it is transmitted to the second terminal of the second group. On the other hand, the second terminal generates address range information in which both the first and second data are null, and transmits it to the second terminal together with the second group address list stored by itself. Thus, the first terminal acquires the second group address list, and the second terminal acquires the first group address list.

  Then, each terminal (including the first and second terminals) that has received the address range information transmitted from another terminal and the address list of another group includes (1) the first address range information received. If the data (received first data) is null, the first data is received, the first data is received, the second data is self-addressed, address range information is generated, and the generated address range information is received. The address list of the other group is transmitted to any one terminal that is less than the self address.

  In addition, each terminal (2), when the received first data is not null, generates address range information having the first data as the received first data and the second data as the self address, and the generated address range The information and the received address list are transmitted to one terminal in the same group having an address larger than the received first data and less than the self address.

  Each terminal (3), if the second data (received second data) of the received address range information is null, the address range information with the first data as its own address and the second data as null And the generated address range information and the received address list are transmitted to one terminal in the own group having an address equal to or higher than the own address.

  In addition, each terminal generates (4) address range information in which the second data is the second data when the second data of the received address range information is not null and the first data is the self address. The generated address range information and the received address list are transmitted to one terminal in the same group having an address larger than the self address and less than the received second data. The lower limit address indicates the address of the terminal having the minimum address in the group, and the upper limit address indicates the address of the terminal having the maximum address in the group.

  As described above, the address list is transferred to all the terminals. The first and second terminals combine the generated one address range information and the received address list together with the received address list as 1 Since the data is transmitted to only one terminal, the number of data flowing in the group can be greatly reduced as compared with the case of transmitting conventional PING and PONG messages. Moreover, since there is no restriction by TTL, the address list can be transmitted to all terminals.

  According to the invention described in claim 2, since each terminal transmits the address range information generated to the terminal having the intermediate address and the received address list, the address list is efficiently transferred, and the address list Can be transmitted to all terminals in a short time.

  According to the invention described in claim 3, the communication system can be applied to a group configured on the Internet.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a network configuration diagram of a communication system according to the present embodiment. This communication system includes two groups, a group G1 composed of N peers (terminals) X1 to XN and a group G2 composed of M peers Y1 to YM. The peers X1 to XN and the peers Y1 to YM are connected to each other via a communication network NT so that they can communicate with each other.

  The communication network NT is a WAN (Wide Area Network) or LAN (Local Area Network) communication network. The WAN corresponds to a dedicated line or an Internet line. The peers X1 to XN and the peers Y1 to YM are composed of commercially available personal computers equipped with a CPU (central processing unit), RAM (random access memory), ROM (read only memory), hard disk, communication interface (I / F), etc. Has been. The peers X1 to XN and the peers Y1 to YM are installed with predetermined software for causing the computer to function as a peer of the peer-to-peer system, such as Nutera, and a program for causing each peer belonging to a different group to acquire an address list. ing.

  FIG. 2 shows a block diagram of a certain peer P among the peers X1 to XN and peers Y1 to YM. The peer P includes an address list storage unit 11, a self address storage unit 12, a reception unit 13, an address range information generation unit 14, and a transmission unit 15. The address list storage unit 11 is composed of, for example, a hard disk, and stores an address list in which communication addresses of each peer of the group to which the peer P belongs are described. In the present embodiment, since the group G1 and the group G2 exist, the address lists L1 and L2 of the group G1 and the group G2 exist, and each address of the peers X1 to XN is described in the address list L1, and the address list Each address of peers Y1 to YM is written in L2. Accordingly, the peers X1 to XN store the address list L1, and the peers Y1 to YM store the address list L2.

  The self address storage unit 12 is composed of a hard disk, and stores a self address used for communication. In the present embodiment, within the same group, for example, 1 is assigned to peer X1, 2 is assigned to peer X2, and N is assigned to peer XN. To do. Actually, each peer is identified by a numerical value consisting of, for example, an IP address and a port number. In this embodiment, for convenience of explanation, each peer is assigned an address in order from 1 within the same group. It is assumed that

  The receiving unit 13 includes a communication interface such as a communication board and a CPU, and receives various data such as address range information and other group address lists transmitted from other peers.

  The address range information generation unit 14 includes a CPU and stores address range information from other peers received by the reception unit 13, a self address stored in the self address storage unit 12, and an address list storage unit 11. Address range information is generated using the address list of the self group (the group to which the self belongs), and is output to the transmission unit 15. Here, the address range information is composed of data D1 and data D2, and an address or null of a certain peer is set respectively. “null” indicates data that does not specify an address. When the address of a certain peer is set for both data D1 and data D2, the address set for data D2 is larger than the address set for data D1.

  The transmission unit 15 includes a communication interface such as a CPU and a communication board, and receives the address range information of other peers received by the reception unit 13 and the self address stored in the self address storage unit 12. The peer that transmits the address list received by the unit 13 and the address range information generated by the address range information generation unit 14 is determined, and the address range information and the address list are transmitted to the determined peer.

  FIG. 3 is a flowchart showing the operation of the communication system according to the present embodiment. FIGS. 4A to 4C are diagrams showing the flow of data between peers. Hereinafter, the operation of the communication system according to the present embodiment will be described with reference to FIGS. 3 and 4. First, in step S1, a certain peer Y1 belonging to the group G2 acquires the address of a certain peer X1 belonging to the group G1. Here, the peer Y1 acquires the address of the peer X1, for example, by receiving an input from the user. The peer Y1 is one peer arbitrarily selected from the peers Y1 to YN belonging to the group G2, and the peer X1 is one arbitrarily selected from the peers X1 to XN belonging to the group G1. It is a peer and there is no standard for selection.

  Next, as shown in FIG. 4A, the peer Y1 stores the address list L2 of the group G2 stored by itself, the address range information [null, null] of data D1 = null, data D2 = null, The address is transmitted to the peer X1 (step S2).

  The peer X1, which has received the address list L2, the address range information [null, null], and the address of the peer Y1, as shown in FIG. 4C, the address list L1 of the group G1 stored by itself and the address Range information [null, null] is generated and transmitted to the peer Y1 (step S3).

  The peer X1 that has transmitted the address list L2 and the address range information [null, ull] performs address list transfer processing (step S4), generates address range information, and combines the received address list L2 with the peer X2 ˜XN to any one or two peers. In the case of FIG. 4B, the peer X1 transmits the received address list L2 and the generated address range information to the peers X2 and X3. The address list transfer process shown in step S4 is executed by each of the peers X1 to XN that have received the address list L2, and the address list L2 is transferred to all peers belonging to the group G1. This process will be described later.

  The peer Y1 that has received the address list L1 transmitted from the peer X1 executes address list transfer processing (step S5), generates address range information, and combines the received address list L1 with the peers Y2 to YM. To either one or two peers. In the case of FIG. 4C, the peer Y1 transmits the address range information and the address list L1 to the peers Y2 and Y3. The address list transfer process shown in step S5 is executed by each of the peers Y1 to YM that has received the address list L1, and the address list L1 is transferred to all peers belonging to the group G2. This process will be described later.

  5 and 6 are flowcharts showing the address list transfer process shown in steps S4 and S5. The address list transfer process will be described below using this flowchart. Since the address list transfer process is a process common to all peers, a case where a certain peer P belonging to the group G1 or the group G2 receives the address list L1 or L2 will be described as an example.

  In step S101, when the receiving unit 13 receives address range information with null data D1 and another group address list from another peer (YES in step S101, YES in step S102), an address range information generating unit 14 determines whether a peer having an address smaller than the self address exists in the self group (step S103). If it is determined that the peer exists (YES in step S103), the process proceeds to step S104. On the other hand, in step S101, when the receiving unit 13 has not received the address range information and the address list of another group (NO in step S101), the process returns to step S101.

  In step S104, the address range information generation unit 14 generates address range information [null, self address] in which data D1 = null and data D2 = self address (step S104).

  In step S105, the transmission unit 15 sends the address range information [null, self address generated in step S104 to one peer of the self group having an intermediate address within the address range that is equal to or greater than the lower limit address and less than the self address. ] And the received address list. In this case, when there is only one peer having an address lower than the self address, that is, when the self address is the second smallest address, the transmission unit 15 sends the received address list to the lower limit address peer, The generated address range information is transmitted. Here, the lower limit address means an address having the lowest number among peers constituting the group.

  Specifically, the transmission unit 15 determines an intermediate address by calculating (lower limit address + self address) / 2. For example, when the self address = 5, the transmission unit 15 determines (1 + 5) / 2 = 3 as an intermediate address. When (lower limit address + self address) / 2 becomes a decimal, the transmission unit 15 determines an intermediate address by rounding up or down after the decimal point. For example, when self address = 6, since (1 + 6) /2=3.5, the transmission unit 15 determines 3 or 4 as an intermediate address.

  On the other hand, in step S103, when there is no peer less than the self address in the self group (NO in step S103), the address range information generation unit 14 goes through the processes in steps S104 and S105, and performs the process in step S109. Proceed.

  On the other hand, when the receiving unit 13 receives address range information in which the data D1 is not null (hereinafter, this data D1 is referred to as received data D1) in step S102 (YES in step S101, NO in step S102). The address range information generation unit 14 determines whether or not there is a peer having an address larger than the received data D1 and less than the self address. If there is a peer (YES in step S106), the process proceeds to step S107.

  In step S107, the address range information generating unit 14 generates address range information [received data D1, self address] where data D1 = received data D1 and data D2 = self address.

  In step S108, the transmission unit 15 sends the address range information [received data D1, self address] generated in step S107 to one peer having an intermediate address among the addresses larger than the received data D1 and less than the self address. And the address list received in step S101. The intermediate address is determined by the same method as in step S105.

  On the other hand, when there is no peer in the own group that is larger than the received second data and less than the self address in step S106 (NO in step S106), the address range information generation unit 14 passes through the processes in steps S107 and S108. Then, the process proceeds to step S109.

  In step S109, if the second data of the received address range information (hereinafter referred to as “received data D2”) is null (YES in step S109), the address range information generation unit 14 is larger than the self address. It is determined whether a peer having an address exists in its own group (step S110). If it is determined that it exists (YES in step S110), data D1 = self address, data D2 = null address range information [self Address, null] is generated (step S111).

  In step S112, the transmission unit 15 uses the same method as in step S105 to send the address range information generated in step S111 [self address, null] and the address list received in step S101. Further, when there is only one peer larger than the self address, that is, when the self address is the second largest address, the transmission unit 15 sets the received address list and the generated address range information as the upper limit address. (S112).

  On the other hand, in step S110, when a peer having an address larger than the self address does not exist in the self group (NO in step S110), the address range information generation unit 14 passes through the processes of steps S111 and S112.

  On the other hand, when the receiving unit 13 receives address range information in which the second data is not null in step S109 (NO in step S109), the address range information generating unit 14 is greater than the self address and less than the received data D2. It is determined whether or not a terminal having an address exists in the own group. If it is determined that the terminal exists (YES in step S113), address range information [self address] in which data D1 = self address and data D2 = received data D2 , Received data D2] is generated (step S114).

  In step S115, the transmission unit 15 sends the address range information [self address, reception data D2] generated in step S114 to one peer having an intermediate address larger than the self address and less than the reception data D2, and step S101. Send the address list received at.

  On the other hand, in step S113, when a peer having an address larger than the self address and less than the received data D2 does not exist in the self group (NO in step S113), the address range information generation unit 14 performs the processing in steps S114 and S115. Through.

  Next, a specific example of the data flow in the communication system will be described with reference to the flowcharts of FIGS. 5 and 6 and the drawing of FIG. FIG. 7 is a diagram for explaining the flow of data. In this specific example, the peer X1 indicates a certain peer belonging to the group G1, and the group G2 is configured by peers Y1 to Y10 including a total of ten units. The peers Y1 to Y10 have addresses A1 (= 1) to A10 (= 10), respectively. Further, it is assumed that peer X1 knows address A5 of peer Y5.

  First, the peer X1 generates address range information [null, null] of data D1 = null and data D2 = null, and sends it to the peer Y5 together with the address list L1. The peer Y5 that has received the address range information [null, null] and the address list L1 has received data D1 null (YES in step S102), and a peer having an address less than the self address A5 exists in the group G2. (YES in step S103), address range information [null, A5] of data D1 = null and data D2 = A5 (= 5) is generated (step S104). Then, the generated address range information [null, A5] and the received address list L1 are transmitted to the peer Y3 having an intermediate address equal to or higher than the lower limit address A1 of the group G2 and less than the self address A5 (step S105).

  Further, since the peer Y5 has received the address range information [null, null] in which the received data D2 is null (YES in step S109), the data D1 = self address and the data D2 = null address range information [A5, null ] Is generated (step S110). Then, the generated address range information [A5, null] and the received address list L1 are transmitted to the peer Y8 having an intermediate address larger than the self address A5 and less than the upper limit address A10 of the group G2 (step S112).

  The peer Y3 that has received the address range information [null, A5] and the address list L1 has the received data D1 null (YES in step S102), and a peer having an address less than the self address A3 exists in the group G2. Therefore (YES in step S103), address range information [null, A3] in which data D1 = null and data D2 = self address is generated (step S104). Then, the generated address range information [null, A3] and the received address list L1 are transmitted to the peer Y2 having an intermediate address that is not less than the lower limit address A1 of the group G2 and less than the self address (step S105).

  Further, since the received data D2 is not null (NO in step S109) and there is a peer having an address larger than the self address (YES in step S113), peer Y3 has data D1 = self address A3 and data D2 = received. Address range information [A3, A5] as data D2 is generated (step S114). Then, the generated address range information [A3, A5] and the received address list L1 are transmitted to the peer Y4 having an intermediate address larger than the self address A3 and less than the received data D2 (= A5) (step S115). ).

  On the other hand, in the peer Y8 that has received the address range information [A5, null], the received data D1 is not null (NO in step S102), and there is another peer in the address range that is larger than the received data D1 and less than the self address A8. In order to do this (YES in step S106), address range information [A5, A8] with data D1 = received data D1 and data D2 = self address A8 is generated (step S107). Then, the generated address range information [A5, A8] and the received address list L1 are transmitted to the peer Y6 having an intermediate address larger than the self address A8 and less than the self address (step S108).

  Peer Y8 receives address range information [A5, null] in which reception data D2 is null (YES in step S109), and there is a peer having an address larger than self address A8 (YES in step S110). Address range information [A8, null] of data D1 = self address A8 and data D2 = null is generated (step S111). Then, the address range information [A8, null] generated for the peer Y9 having an address larger than the self address A8 and not more than the upper limit address A10 and the received address list L1 are transmitted (step S112).

  The peer Y2 that has received the address range information [null, A3] and the address list L1 has the received data D1 null (YES in step S102), and there is a peer less than the self address A2 (YES in step S103). ), Data D1 = null, and data D2 = self address A2 address range information [null, A2] is generated (step S104). Then, the address range information [null, A2] and the address list L1 are transmitted to the peer Y1 having an address less than the self address A2 (step S105).

  Further, since the peer Y2 is larger than the received data D2 (= A3) and does not have a peer less than the self address A2 (NO in step S113), the process is terminated through steps S114 and S115.

  The peer Y4 that has received the address range information [A3, A5] has received data D1 that is not null (NO in step S102), and there is no peer that is larger than the received data D1 and less than its own address A4 (NO in step S106). ), Steps S107 and S108 are passed through, and the process proceeds to Step S109.

  Further, since the received data D2 (= A5) is not null (NO in step S109) and there is no peer larger than the self address A4 and less than the received data D2 (NO in step S113), the peer Y4 has no data in step S114 and Through S115, the process is terminated.

  The peer Y6 that has received the address range information [A5, A8] has received data D1 that is not null (NO in step S102), and is larger than the received data D1 (= A5), and there is no peer that is less than the self address A6 ( NO in step S106), the process of steps S107 and S108 is passed, and the process proceeds to step S109.

  Further, since the received data D2 (= A8) is not null (NO in step S109), the peer Y6 is a peer that is larger than the self address A6 and less than the received data D2 (YES in step S113), so the data D1 = self Address range information [A6, A8] with address A6, data D2 = received data D2 (= A8) is generated (step S114). Then, the generated address range information [A6, A8] and the received address list L1 are transmitted to the peer Y7 having an intermediate address larger than the self address A6 and less than the received data D2 (= A8) (step S115). ).

  The peer Y9 that has received the address range information [A8, null] and the address list L1 has received data D1 not null (NO in step S102) and is larger than the received data D1 (= A8) and less than the self address A9. Since there is no peer (NO in step S106), the process proceeds to step S109 through steps S107 and S108.

  Further, since the reception data D2 is null (YES in step S109) and there is a peer having an address larger than the self address A9 (YES in step S110), the peer Y9 has data D1 = self address A9, data D2 = Address range information [A9, null] to be null is generated (step S111). The address range information [A9, null] and the address list L1 are transmitted to the upper limit address peer Y10 (step S112).

  The peer Y1 that has received the address range information [null, A2] and the address list L1 has the received data D1 null (YES in step S102), and there is no peer larger than the received data D1 and less than the self address A1. Therefore (NO in step S103), the process proceeds to step S109 through steps S104 and S105.

  Further, since the reception data D2 is not null (NO in step S109) and the peer Y1 has no peer larger than the self address A1 and less than the reception data D2 (= A2) (NO in step S113), the peer Y1 The process is terminated through S115.

  The peer Y7 that has received the address range information [A6, A8] and the address list L1 has received data D1 not null (NO in step S102), is larger than the received data D1 (= A6), and is less than the self address A7. Since there is no peer (NO in step S106), the process is terminated through steps S107 and S108.

  Peer Y7 passes through steps S114 and S115 because received data D2 is not null (NO in step S109) and there is no peer larger than self address A7 and less than received data D2 (NO in step S113). To finish the process.

  The peer Y10 that has received the address range information [A9, null] has received data D1 not null (NO in step S102), and there is no peer larger than the received data D1 and less than its own address (NO in step S106). Through steps S107 and S108, the process is terminated.

  Further, since the reception data D2 is null (YES in step S109) and there is no peer larger than the self address A10 (NO in step S110), the peer Y10 passes through steps S111 and S112 and ends the process.

  As described above, according to this communication system, the difference between the data D1 and the data D2 is reduced as the address range information generated by each peer is newly generated. In addition, each peer transfers the address list only to one peer between the received data D1 and the self address and one peer between the self address and the received data D1. On the other hand, when there is no other peer between the received data D1 and the self address, each peer does not transfer the address list to one peer in the meantime and between the self address and the received data D2. If there is no other peer, the address list is not transferred to one peer during this period.

  Therefore, the address list of another group can be transmitted to all peers belonging to the same group without broadcasting the address list, and the number of data flowing in the group can be greatly reduced. In addition, since there is no limit on the number of transfers by TTL as in the case of broadcasting, the address list can be reliably transferred to all peers.

  Further, since the address list is transferred to an intermediate peer between the received data D1 and the self address, or an intermediate peer between the self address and the received data D2, as shown in FIG. The number increases and the time for the address list to be transferred to all peers can be reduced.

1 shows a network configuration diagram of a communication system according to the present embodiment. FIG. 2 shows a block diagram of a certain peer constituting the communication system. It is a flowchart which shows operation | movement of the communication system concerning this Embodiment. (A)-(c) is drawing which shows the flow of the data between peers. It is the flowchart which showed the address list transfer process. FIG. 6 is a flowchart continued from FIG. 5 showing an address list transfer process. FIG. It is drawing for demonstrating the data flow of this communication system. In the conventional communication system, it is a figure which shows the flow of the PING message and PONG message transmitted when the terminal P1 is newly added with respect to the group which consists of the terminals P2-P8, (a) is a PING message. The flow is shown, and (b) shows the flow of the PONG message.

Explanation of symbols

G1 G2 Group L1 L2 Address list X1 to YN Peer Y1 to YM Peer 11 Address list storage unit 12 Self address storage unit 13 Reception unit 14 Address range information generation unit 15 Transmission unit

Claims (4)

A first group composed of one or more terminals, and a second group composed of one or more terminals communicably connected to the first group, each terminal comprising: A communication system that includes a storage unit that stores an address list in which addresses of all terminals in the same group are given, and which is provided with an address consisting of a numerical value unique to each terminal, and allows each terminal to acquire an address list of the other group Because
The first terminal belonging to the first group generates address range information in which the first and second data are null, and generates the generated address range information and the first group address list in the second Send it to your device,
The second terminal generates address range information in which the first and second data are null, transmits the generated address range information and a second group address list to the first terminal,
Each terminal, including the first and second terminals,
When the first data of the received address range information is null,
One unit that generates address range information in which the first data is null and the second data is a self address, and the generated address range information and the received address list have a smaller address than the self address in the same group. To your device,
If the first data of the received address range information is not null,
The first data of the address range information having received the first data, the address range information having the second data as its own address is generated, and the generated address range information and the received address list are within the same group, Transmitting to one terminal having an address larger than the first data and smaller than the self address;
When the second data of the received address range information is null,
Address range information in which the first data is a self address and the second data is null is generated, and the generated address range information and the received address list have a larger address than the self address in the same group. To one device,
If the second data of the received address range information is not null,
Generate address range information in which the first data is the self address and the second data is the second data of the address range information received, and the generated address range information and the received address list are in the same group, A communication system characterized by transmitting to one terminal having an address larger than a self address and smaller than the second data. Each terminal
When address range information with null as the first data and self address as the second data is generated, the address range information generated in the terminal having an intermediate address between the upper limit address and the self address of the same group is received. Send address list and
When the address range information having the first data as the self address and the second data as the upper limit address is generated, the address range information generated in the terminal having an intermediate address between the self address and the upper limit address of the same group, Send the received address list and
When the address range information in which both the first and second data are not null is generated, the generated address range information, the received address list, and the terminal having an intermediate address between the first data and the second data The communication system according to claim 1, wherein:   The communication system according to claim 1 or 2, wherein the address includes an IP address and a port number. A first group composed of one or more terminals, and a second group composed of one or more terminals communicably connected to the first group, each terminal comprising: An address list that is provided with a memory means for storing an address list in which addresses of all terminals in the same group are described, and which is provided with an address consisting of a numerical value unique to each terminal, and that causes each terminal to acquire an address list of the other group An acquisition method,
The first terminal belonging to the first group generates address range information in which the first and second data are null, and generates the generated address range information and the first group address list in the second Send it to your device,
The second terminal generates address range information in which the first and second data are null, transmits the generated address range information and a second group address list to the first terminal,
Each terminal, including the first and second terminals,
When the first data of the received address range information is null,
One unit that generates address range information in which the first data is null and the second data is a self address, and the generated address range information and the received address list have a smaller address than the self address in the same group. To your device,
If the first data of the received address range information is not null,
The first data of the address range information having received the first data, the address range information having the second data as a self address is generated, and the generated address range information and the received address list are within the same group, Transmitting to one terminal having an address larger than the first data and smaller than the self-address,
When the second data of the received address range information is null,
Address range information in which the first data is a self address and the second data is null is generated, and the generated address range information and the received address list have a larger address than the self address in the same group. To one device,
If the second data of the received address range information is not null,
Generate address range information in which the first data is the self address and the second data is the second data of the received address range information, and the generated address range information and the received address list are within the same group, An address list acquisition method comprising: transmitting to one terminal having an address larger than a self address and smaller than the second data.

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