KR100316248B1 - A method for reducing the number of connections between ELAN or LIS in MPOA network - Google Patents

Abstract

The present invention is the biggest disadvantage of the multiprotocol over ATM (hereinafter referred to as MPOA) in providing MPOA service in the asynchronous transmission equipment (hereinafter referred to as ATM-LAN) that provides a local area network service over ATM. To address the lack of phosphorus scalability. Specifically, the present invention relates to a method of minimizing the number of redundant VCC connections between ELANs or LISs to provide scalability in an MPOA network by preventing a full mesh structure that may occur in the MPOA network.

In the present invention, when the source MPC wants to communicate with an objective MPC belonging to another emulated local area network (hereinafter referred to as ELAN) or a logical Internet protocol segment (hereinafter referred to as LIS). If there is another MPC or another virtual channel connection (hereinafter referred to as VCC) that communicates with the LIS, information is sent to the currently communicating MPC or VCC. In addition, it analyzes the information received from the MPC and delivers the information to the destination MPC if the information is not received. All of this processing is controlled by an MPOA server (hereinafter referred to as MPS) that manages the MPC. When the method of the present invention is applied, a worst case fully connected structure may be achieved between all ELANs and between ELANs, but a completely connected structure of the entire MPOA network may be avoided. Therefore, it is possible to provide scalability of the MPOA network.

Description

A method for reducing the number of connections between LANs or LISs to provide scalability in MPIO network {A method for reducing the number of connections between ELAN or LIS in MPOA network}

The present invention is the biggest disadvantage of the multiprotocol over ATM (hereinafter referred to as MPOA) in providing MPOA service in the asynchronous transmission equipment (hereinafter referred to as ATM-LAN) that provides a local area network service over ATM. To address the lack of phosphorus scalability.

Specifically, the present invention relates to a method of minimizing the number of redundant VCC connections between ELANs or LISs to provide scalability in an MPOA network by preventing a full mesh structure that may occur in the MPOA network.

1 illustrates a representative example of an MPOA network providing a local area network service in an ATM network.

As shown in the figure, the MPOA network 10 comprises at least one MPOA client (MPOA Client, hereinafter referred to as MPC: 15, 18, 22, 24) and an MPOA Server (MPOA Server, hereinafter referred to as MPS: 17, 21). It is.

The MPCs 15, 18, 22, and 24 may be connected to the existing local area network Token Ring 13 or Ethernet 25. In addition, several terminals 11 and 12 may be connected to the token ring 13, and several terminals 26 and 27 may be connected to the Ethernet. In addition, a certain MPC (18, 22) may be connected to only one terminal (19, 23).

The terminal connected to the local area network should be able to communicate with the terminal connected to the ATM network. This role is played by the MPC. Therefore, the terminal connected to the MPC or the existing local area network is provided with the MPOA service as a function of the MPC. The MPCs are connected to the MPS / routers 17 and 21 by a virtual channel connection (hereinafter referred to as VCC).

The MPS coexists with a router. The router's function provides a path for communication between terminals when the terminals exist in different LIS in the existing local area network. MPS works with the help of routers to help the MPC find the destination MPC. MPS does not have to be physically in the same location as the router, but logically exists because it requires the functionality of the router.

The MPS and the MPS are connected to the VCC 20. All MPSs are not connected by direct VCC, but the connection state is defined by router configuration. If two routers are directly connected to each other, a direct VCC is set between the two MPSs. If there is no direct connection between the two routers, the VCC connection is not established between the MPSs. Therefore, in order to efficiently configure the structure of the MPOA network structure, the structure of the routers must be efficiently configured.

2 illustrates an example of a connection state configured by the existing MPOA method.

The MPOA network is divided into an entry side 31 and an exit side 32. The entry side 31 means entering the MPOA network according to the incoming and outgoing criteria, and the exit side 32 has the meaning of exiting the MPOA and entering the local area network service. There is a line 55 for logically separating the entry side 31 and the exit side 32 from each other. The meaning of this line 55 does not mean that the entry side 31 and the exit side 32 are physically connected to each other, but only the entry and exit in the MPOA network.

There are several routers / MPSs 34 and 35 between the entry side 31 and the exit side 32. These routers / MPSs 34 and 35 provide a route to carry information to the destination. There is a connection 33 between the entry router / MPS 34 and the exit router / MPS 35, as described above, rather than a direct ATM connection between each other, there are several routers / MPS in the middle, It is a connected connection. It is assumed that the entry side MPC 36 and the MPC 37 exist in the same ELAN or LIS and the exit side MPC 38 and MPC 39 also exist in the same ELAN or LIS. The components of the MPOA, that is, the routers / MPSs 34 and 35 and the MPCs 36, 37, 38 and 39, all hold MPOA cache information 40 to 45, respectively.

The existing MPOA process is described as follows.

The MPS and MPCs are connected (47, 48, 49, 50) by ATM VCC. If the entry MPCs 36, 37 need to communicate information directly to the exit MPCs 38, 39, the entry MPCs 36, 37 use the connecting lines 47, 48 to the entry MPS 34. To request the address of the exit MPCs 38 and 39.

The entry MPS 34 receives an address interpretation request from the entry MPCs 36 and 37 and makes an address interpretation request in the direction of the exit MPS 35 with the help of a router.

Upon receipt of an address interpretation request from the entry MPS 34 at the exit MPS 35, the cache is validated in order to find the appropriate exit MPCs 38 and 39 and prepare it for connection with the entry MPCs 36 and 37. Create and send a request message. The exit MPCs 38 and 39 include the information required for address resolution and generate a cache validation response and send it to the exit MPS 35. The exit side MPS 35 makes an address resolution response message as a cache validation message and delivers it to the entry side MPS 34, which is the source of the address resolution request, along the path through which the address resolution request has been delivered.

The entry MPS 34 sends response information to the entry MPCs 36 and 37 with reference to the address interpretation response message of the exit MPS 35. Referring to the response information of the entry side MPS 34, the entry side MPCs 36 and 37 communicate directly with the outlet side MPCs 38 and 39 by establishing direct connections 51, 52, 53 and 54.

In the course of all this processing, MPS and MPC each create a cache (40 to 45) to store and maintain the information they need. The contents stored in the caches 40 to 45 may include other information in addition to the information mentioned in the drawings. However, in the present invention, only the information necessary to describe the information on the connections 51, 52, 53, and 54 between the four MPCs is described. It was.

The entry MPC 36 owns two terminals, and the two terminals communicate with the exit MPCs 38 and 39 and the connections 51 and 53, respectively. The entry MPC 36 is stored in the cache 42 and the exit MPCs 38 and 39 are stored in a part of the caches 44 and 45 for information on the communication contents between the MPCs. The caches 40 and 41 of the routers / MPSs 34 and 35 also contain information in this communication. The source router / MPS 35 is labeled with the source router / MPS 34. This is a phenomenon occurring in the local area network, the source is not represented by the address of the terminal of the entry side MPC (36, 37), but is represented by the address of the entry side router / MPS (34).

The other MPC 37 of the entry side maintains only one terminal, so that one terminal is connected to the two exit side MPCs 38 and 39 (52, 54). Information about it is stored in the cache 43 of the entry MPC and in the caches 44 and 45 of the exit MPC. The caches 40 and 41 of the MPS 34 and 35 also contain this information.

However, as shown in FIG. 2, four connection settings are made between four MPCs.

3 represents the worst case when the connection is established by the conventional method.

If there are eight MPCs in the entire MPOA network as shown in FIG. 3 and all eight MPCs communicate at the same time, it may vary depending on the ELAN or LIS configuration of each MPC, but in the worst case, there may be 56 connection settings (full connection). However, the MPOA network is a communication protocol for large networks, and the number of MPCs is large. In the worst case, the number of connections is quite large.

Until now, the size of the MPOA network has been limited because of the concern about the complete structure of the short-range MPOA. Therefore, when constructing a large network with MPOA, there was no choice but to separate the MPOA into several networks.

A paper on providing MPOA scalability includes the Analysis of Logical Router Control Protocol Alternatives, published by J. Logan and S. Brimm in the ATM Forum (No. 99-0352).

In this paper, the network is composed of blocks of 'logical routers' that are capable of high-speed scalability and are composed of different kinds of networks, and together, these logical routers are collected to form one huge MPOA network.

In other words, the MPOA network is divided into several logical routers, and one logical router operates as a virtual private network (VPN). The logical router consists of one or more forwarders that carry information between the router server and the logical router. The newly defined router server and the forwarder communicate using the Logical Router Control Protocol (LRCP).

However, this paper is a contribution of an international standards body, and the details are not yet defined. However, it only defines abstract contents such as to use cache similar to the protocol used by MPOA and to maintain cache information generated by communication between different logical routers.

Accordingly, an object of the present invention is to provide a network in an MPOA network composed of several simulated local area networks (ELANs) and logical Internet Protocol Segments (LISs). To minimize the number of redundant VCC connections between ELANs or LISs to provide scalability

1 is a block diagram of an MPOA network to which the present invention is applied

2 is an exemplary view showing a connection state of a network using a conventional MPOA method

3 is a worst case diagram when establishing a connection in an MPOA network using a conventional method.

Figure 4 is a connection state diagram in the MPOA network using the method according to the present invention

5 is a flow chart of the entry side MPS of FIG.

6 is a flow chart of the exit MPS of FIG.

7 is a flow chart of the entry side MPC of FIG.

8 is a flow chart of the exit MPC of FIG.

Explanation of symbols on the main parts of the drawings

63: entry router / MPS

64: exit router / MPS

65: Router / MPS Connection

66, 67: entry MPC

68, 69: exit MPC

70 to 75: Cache

In order to achieve the above object, the present invention reduces the number of connection lines between the ELAN or LIS by utilizing the communication in the ELAN or LIS that already exists in the MPOA network, thereby reducing the number of connection settings in the MPOA network as a whole. It characterized in that to provide.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

4 illustrates a connection state in an MPOA network using a method of minimizing the number of redundant VCC connections between ELANs or LISs according to an embodiment of the present invention. As shown in the figure, the configuration of the MPOA network is basically the same as in FIG. However, the configuration of connection settings between MPCs is different.

First, it is assumed that the connection 76 between the entry MPC 66 and the exit MPC 68 already exists between MPCs existing in different ELANs or LISs. 4 will be described on the assumption that the remaining connections 77 and 78 do not exist.

When the entry MPC 67 wishes to communicate with the exit MPC 68, the entry MPC 67 requests the entry MPS 63 for address resolution of the exit MPC 68.

The entry MPS 63 checks its cache 70 before sending an address resolution request message to the exit MPS 64. At this time, the entry side MPS 63 checks whether there is a connection established with the outlet side MPC 68 among the MPCs connected with it. As a result, the MPS cache 70 confirms that the entry MPC 66 and the exit MPC 68 are in communication with each other. The entry MPS 63 then sends a response message to the entry MPC 67 based on the information of the cache 70 and the information on the exit MPC 68. At this time, the address of the destination is not indicated as the exit MPC 68, but the ATM address of the entry MPC 66 which is already communicating with the exit MPC 68 is transmitted.

The entry MPC 67 receives the response of the entry MPS 63 and sets the connection 77 with the entry MPC 66 according to the address of the destination to send the information through the connection. Then, when the entry MPC 66 receives the information from the entry MPC 67, it checks the destination and knows that it is not its own information, and sends the information to the exit MPC 68.

In addition, when the entry side MPC 67 also wants to communicate with the exit side MPC 69, it sends an address interpretation request to the entry side MPS 63 asking for the address of the exit side MPC 69, as in the conventional method. The entry side MPS 63 receives the message and inspects its cache 70, and sends an address interpretation request message to the exit side MPS 64 knowing that it is a destination that cannot be resolved.

The exit MPS 64 receives the address resolution request message and sends a cache validation request message to the exit MPC 69 in the same manner as the general MPOA process. Upon receiving the cache validation response message from the exit MPC 69, it checks its own cache 71 to see if a connection establishment with the same source already exists. At this time, the source in the address interpretation request message is the entry side MPS (63), so the cache 71 to check the entry side MPS (63). However, since the entry MPC 66 and the exit MPC 68 are already communicating through the connection 76, the exit MPC 68 is informed of the exit MPC 69 to the exit MPC 68 based on this information. It is required to establish 69 and internal connection 78. The outlet MPC 68 establishes a connection 78 with the outlet MPC 69 and receives the information received by the outlet MPC 69. The outlet MPC 68 uses the new connection 78 to transmit information to the outlet MPC 69. To pass. The exit MPS 64 carries the ATM address of the exit MPC 68 in the address interpretation response message to the entry MPS 63.

The entry MPS 63 receives the response message and knows that the destination is the exit MPC 68 rather than the exit MPC 69, and among the entry MPCs connected to it in its cache 70, the exit MPC ( 68) Check if there is a connection setting. As a result of the inspection, it is confirmed that the entry MPC 66 and the exit MPC 68 are already in communication. Accordingly, the entry side MPS 63 sends the entry side MPC 67 the ATM address of the entry side MPC 66 as the destination address. Then, the entry side MPS 63 sends a new incoming / outgoing information to the entry side MPC 66 and sends a message to the exit side MPC 68 when it receives the information transmitted to the exit side MPC 69.

The entry MPC 67 confirms that the destination ATM address is the entry MPC 66, and since the connection 77 already exists, it connects the information to be sent to the exit MPC 69 without establishing a new connection. Pass through. The entry MPC 66 knows that the destination is not itself, and transmits the information of the exit MPC 69 to the exit MPC 68. The outlet MPC 68 receives this information and delivers the information to the outlet MPC 69.

If the entry MPC 66 has to deliver information to the exit MPC 69, there is information necessary for address interpretation in its own cache 72, so the entry side MPS 66 does not have to request entry interpretation from the entry MPS 63. Information to be sent to MPC 69 is sent to exit MPC 68 using connection 76. The exit MPC 68 receives this information and verifies that it is not its own information and passes the information through the connection 78 to the exit MPC 69, which is the correct destination.

Thus, in order for the entry side MPC 67 to communicate with the exit side MPC 68 or 69, the internal connection 1 (77) information is transmitted, and the entry side MPC 66 receives this information to the exit side MPC 68. Pass through connection 76. The exit MPC 68 analyzes the received information and processes the received information in the same manner as the existing method. If the exit MPC 68 sends information to the other exit MPC 69 existing in the same ELAN and LIS, the internal connection 2 ( Information is transmitted to the MPC 69 at the exit side.

The connection method in the MPOA network described above will be described in more detail with reference to the flowcharts of FIGS. 5 to 8. It is described here based on the structure of FIG. 4, and assumes that connection number 1 76 already exists between the entry side MPC 66 and the outlet side MPC 68 as described in FIG. 4. In addition, the contents of the present invention will be described on the assumption that the remaining internal connections, the internal connection 1 (77) and the internal connection 2 (78) are not set yet.

5 is an operation flowchart of the entry side MPS.

When the entry side MPS receives an address interpretation request for the destination from the entry side MPC 67 (S101), it checks whether the address interpretation information of the destination exists in its cache 70 (S102). If there is no address analysis information of the destination in the cache 70, the process branches to step S106 to perform a general MPOA function.

However, if it is confirmed in step S102 that the address analysis information of the destination exists in its cache 70, step S103 is performed. For example, if the destination in the address interpretation request message is me 60, information exists in the cache 70 of the entry side MPS 63, and the flow advances to step S103.

The information in the cache 70 of the entry MPS 63 does not exist indefinitely, but only for a specified time, that is, for a valid period. The validity period is the time specified by the system operator. Typically, the time specified is from 20 minutes to infinity.

Therefore, if the destination address exists in the cache 70, it is checked whether the validity period is sufficient (S103). If it is confirmed that the valid period is not sufficient, the flow branches to step S106 to perform the general MPOA function.

However, in step S102, if the validity period of the destination address in the cache 70 is sufficient, the entry MPS 63 requests the destination address interpretation without having to ask the destination MPS 64 for the destination information. The response to the address resolution is transmitted to the entry MPC 67. In this case, the address of the destination MPC 66 does not exist, but includes the address of the entry MPC 66 to transfer the information of the entry MPC 67 to the destination (S104).

The entry side MPC 67 sets up the entry side MPC 66 and the internal connection 1 77 present in the same ELAN / LIS, and then transmits the information to be sent to the destination through the internal connection 1 77.

The MPOA function uses the Next Hop Resolution Protocol (hereinafter referred to as NHRP), which also includes the NHRP network. Thus, the address interpretation may not only consist of MPSs but also deliver information such as address interpretation request / response to an NHRP server (NHRP Server; hereinafter referred to as NHS).

When the entry MPS 63 performs the general MPOA function and requests the destination MPS or NHS to resolve the destination address, the destination MPS 63 receives an address interpretation response from the destination MPS or NHS (S107). Then, the entry MPS 63 checks whether the address of the destination included in the response, that is, the information of the exit MPC, exists in its cache 70 (S108).

As a result of the check, if the information of the exit MPC does not exist in the cache 70, the flow branches to step S106 to perform a general MPOA function. In other words, when there is no connection establishment between the current entry MPCs and the exit MPCs, the exit MPC information received from the exit MPS or the NHS is information about the destination exit MPC. Therefore, connection should be established by performing general MPOA function.

However, if there is an address of the exit MPC received in response to the cache 70 in step S108, it is checked whether the entry MPC requesting the address interpretation and the entry MPC present in the cache 70 are the same (S109). This is because the entry MPC may request to resolve the address to the same destination multiple times.

As a result of checking in step S109, if it is the same, the flow branches to step S106 to perform a general MPOA function.

In other words, if a connection setup already exists between the entry side MPC and the exit side MPC that require address resolution, communication is performed through the connection. For example, if a connection is established between the entry MPC 66 and the exit MPC 68 and the entry MPC 66 wants to communicate with another exit MPC 69, the connection number is already connected. Information is transmitted through 1 (76). Then, the outlet MPC 68 checks the destination and delivers it to the other outlet MPC 69 through the internal connection 2 78 if it is not delivered to itself. Setting of the internal connection 2 78 is made by the control of the outlet side MPS 64, which will be described in detail with reference to FIG.

However, if the entry side MPC requesting the address analysis in step S109 and the entry side MPC present in the cache 70 are not the same, the valid period of the cache 70 is newly reset (S110).

Then, the ATM address of the entry MPC in which the connection establishment with the exit MPC in the cache exists is inserted into the address resolution response message and sent to the entry MPC requesting the address resolution (S111). Then, the entry side MPC requesting the destination address interpretation will establish an internal connection to the address in the response message and send data to the entry side MPC present in the cache 70 through this.

In addition, the entry MPS 63 transmits a new expiration date to the entry MPC in which the connection establishment with the exit MPC in the cache exists and requests resetting of the expiration date, and information on the destination and source to which data is transferred instead. Send (S112).

The processing for other MPOA functions required from the remaining MPOA elements is the same as the general MPOA processing (S105, S106).

6 is an operation flowchart of the exit MPS.

When the exit MPS 64 receives the destination address resolution request from the entry MPS 63, the exit MPS 64 sends a cache valid request message to the exit MPCs 68 and 69. Accordingly, the exit MPCs 68 and 69 send a cache valid response to the exit MPS 64 (S121).

Then, the exit MPS 64 checks whether the address of the entry MPS 63 exists in its cache 71 (S122).

As a result of the check, if the address of the entry MPS 63 does not exist, the process branches to step S128 to perform a general MPOA function, and if it exists, check whether the valid period for the address is sufficient (S123).

If it is determined that the validity period is not sufficient, the process branches to step S128 to perform the general MPOA function. If the validity period is sufficient, the entry side of the exit MPC and the cache 71 to which the entry MPS 63 responds to the cache is valid, It is checked whether the exit side MPC in which connection settings exist is the same (S124).

If the check result is the same, branch to step S128 to perform the general MPOA function, and if not the same, the neighbor MPS / NHS and / or address resolution request not shown in the address interpretation response including the exit MPC address indicated in the cache is requested. It transmits to the side MPS (63) (S125).

Then, the exit MPC indicated in the cache sends information on the exit MPC, which is the final destination of the information, so as to transfer information of the exit MPC, which is the final destination of the information, and instructs to establish a new connection if necessary (S126).

In addition, the exit MPS performs a function of a general MPOA when receiving a request of a function of another MPOA from an MPOA element (S127).

7 is an operation flowchart of the entry side MPC.

When the entry MPCs 66 and 67 receive new validity period and incoming / outgoing call information from the entry side MPS 63 in step S112 of FIG. 5 (S131), the entry side MPCs 66 and 67 transfer the information of the outgoing MPC instead. In order to store the incoming and outgoing information in the cache (S133).

When receiving data from another entry MPC in the ELAN (S134), the data is transmitted to the corresponding destination (exit MPC) with reference to the incoming / outgoing information of the cache (S135).

In addition, when the entry side MPC receives a function request of another MPOA from the MPOA element (S136), it performs the function of a general MPOA (S137).

8 is an operation flowchart of the exit MPC.

The outlet MPCs 68 and 69 store the information of the other outlet MPC and the information of the other outlet MPC in the own cache when receiving the information of the other outlet MPC and the VCC setting request from the outlet MPS 64 in step S126 of FIG. 6 (S141). (S142).

When receiving data from the entry side MPC (S143), it is checked whether the data is for itself (S144). If the check result is its own data, it branches to step S149 to perform a general MPOA processing function, and if it is not its own data, checks whether there is an internal connection with the destination MPC of the destination of the received data (S145).

As a result, if there is an internal connection, the data is immediately sent to the destination exit MPC (S147). However, if there is no internal connection, after establishing a new internal connection with the destination destination MPC (S146), and transmits the data to the destination exit MPC through the internal connection.

In addition, when the outlet side MPC receives a function request of another MPOA from the MPOA element (S148), it performs the function of a general MPOA (S149).

As described above, in the present invention, when a connection already exists between MPCs belonging to different ELANs or LISs in an MPOA network, communication between other MPCs belonging to the corresponding ELANs or LISs is performed through the existing connection. This minimizes the number of redundant VCC connections between ELANs or LISs.

Therefore, applying the present invention can provide scalability to the MPOA network, which has been limited in network size due to concern about occurrence of a fully connected state between MPCs.

The technical spirit of the present invention has been described above with reference to the accompanying drawings, but this is by way of example only and not intended to limit the present invention. In addition, it is obvious that any person skilled in the art can make various modifications and imitations without departing from the scope of the technical idea of the present invention.

Claims (10)

In the MPOA network, which is composed of multiple MPCs connected by ELAN or LIS, and multiple MPSs that coexist with routers and enable the source MPCs to find the destination MPCs with the help of routers, If there is already a connection between MPCs belonging to different ELANs or LISs, then communication between other MPCs belonging to the ELANs or LISs is performed through the existing connection to minimize the number of redundant VCCs between ELANs or LISs. A method of minimizing the number of redundant VCCs between ELANs or LISs providing scalability of an MPOA network. In the MPOA network, which is composed of multiple MPCs connected by ELAN or LIS, and multiple MPSs that coexist with routers and enable the source MPCs to find the destination MPCs with the help of routers, When two or more MPCs in the entry ELAN or the LIS of the MPOA network want to communicate with other MPCs in the same ELAN, The initial connection is established according to the normal MPOA processing procedure. Subsequent connection establishment establishes an internal connection to the entry MPC communicating with the corresponding ELAN or LIS under the control of the entry MPS, and newly transmits the information. The entry MPC communicating with the ELAN or LIS analyzes the destination of the information received through the internal connection and transfers the information to the exit MPC which is not connected, minimizing the number of duplicate VCCs between the ELAN or LIS. A method of minimizing the number of redundant VCCs between ELANs or LISs providing scalability of an MPOA network. The method of claim 2, Upon receiving the destination address resolution request from the entry MPC, the entry MPS checks whether the address interpretation information for the destination already exists in the cache managed by the entry MPC, and if so, communicates with the exit MPC to communicate with the entry MPC. A method for minimizing the number of redundant VCCs between ELANs or LISs that provides scalability of an MPOA network, characterized in that it delivers an address resolution response that inserts an ATM address of another entry side MPC. The method of claim 2, When the destination MPS receives the destination address resolution request from the MPC, it checks whether the address interpretation information for the destination already exists in the cache managed by the entry MPC, and if not, requests the destination MPS to resolve the destination address. Upon receiving the address interpretation response from the exit MPS, check if the address of the response exit MPC exists in the cache managed by the exit MPS. If the address of the response MPC exists in the cache, return the response to the entry MPC requesting the address interpretation. It delivers address resolution response that inserts ATM address of entry MPC which is already communicating with MPC. Number of redundant VCCs between ELANs or LISs that provide scalability of MPOA networks characterized by forwarding incoming and outgoing information consisting of the entry MPC and the exit MPC to transfer information to the entry MPC already communicating with the response exit MPC. Minimization method of. The method of claim 4, wherein The incoming MPC, which is already communicating with the responding exit MPC, receives the incoming / outgoing information consisting of the entry MPC and the exit MPC to transfer information from the entry MPS, and stores the incoming / outgoing information in the cache managed by the entry MPC. A method of minimizing the number of redundant VCCs between ELANs or LISs that provides scalability. The method of claim 4, wherein Answer The incoming MPC that already communicates with the exit MPC checks the destination of the data when receiving data from the MPC existing in the same ELAN or LIS through the internal connection, and refers to the incoming / outgoing information received from the incoming MPS stored in the cache. Minimizing the number of redundant VCC between ELAN or LIS providing scalability of the MPOA network, characterized in that the transmission to the response exit MPC. In the MPOA network, which is composed of multiple MPCs connected by ELAN or LIS, and multiple MPSs that coexist with routers and enable the source MPCs to find the destination MPCs with the help of routers, When two or more MPCs in the exit ELAN or LIS of the MPOA network need to receive information from other MPCs in the same ELAN, The initial connection is established according to the normal MPOA processing procedure. Subsequent connection establishment is controlled by the exit MPS, so that the exit MPC communicating with the corresponding ELAN or LIS establishes an internal connection to the new destination exit MPC and transfers the information to the new destination exit MPC instead. A method of minimizing the number of redundant VCCs between ELANs or LISs providing scalability of an MPOA network, characterized by minimizing the number of redundant VCCs between ELANs or LISs. The method of claim 7, wherein The exit MPS sends a cache valid request message to the exit MPCs upon receiving the destination address resolution request from the entry MPS. Therefore, when the exit MPS receives a cache validation response from the exit MPCs, it checks whether the address of the entry MPS requesting the destination address resolution exists in the cache managed by the exit MPS. If there is an address of the entry MPS requesting the destination address resolution, it already communicates with the entry MPC indicated in the cache instead of inserting the address of the exit MPC requesting the actual destination address interpretation in the address interpretation response to be sent to the entry. Inserts the address of the other exiting MPC and sends it to the entering MPS, ELAN or LIS that provides scalability of the MPOA network, which transmits the new destination exit MPC information to the exit MPC already communicating with the entry MPC in the cache that it manages and requests internal connection. How to minimize the number of redundant VCCs. The method of claim 8, The exit MPC, which already communicates with the entry MPC, receives information about the new destination exit MPC to transfer information from the exit MPS, and stores the information in the cache managed by the exit MPS. How to minimize the number of redundant VCCs between ELANs or LISs that provide The method of claim 9, The exit MPC, which is already communicating with the entry MPC, receives the data from the entry MPC and refers to the exit MPC received from the exit MPS, which is stored in the cache, to the same ELAN or LIS. If the information is received by the other outlet MPC, the ELAN or LIS that provides scalability of the MPOA network, characterized in that if there is no connection with the corresponding outlet MPC, the internal connection is established and data is transmitted using the connection. How to minimize the number of redundant VCCs.