KR100922900B1 - Method for transmitting Data in Distributed Network - Google Patents

Abstract

The present invention relates to a data transmission method in a mobility control structure in which handover control is distributed, and receives a data transmission request to determine a home address group to which the terminal belongs, and forwarding information on the home address group to which the terminal belongs. Adding a tunnel header to data to be transmitted using; And transmitting the data to which the tunnel header is added to at least one network access device including a network access device to which the receiving terminal belongs, thereby eliminating buffering and reducing delay time by the data transmission method. It is possible to make the data transfer more quickly.

Mobile IP, Mobility Control, Home Address

Description

Method for transmitting data in distributed network

The present invention relates to mobility control in a network, and more particularly, to a data transmission method in a mobility control structure in which handover control is distributed.

The present invention is derived from research conducted as part of the IT growth engine technology development project of the Ministry of Information and Communication and the Ministry of Information and Communication Research. [Task Management Number: 2006-S-058-02, Development of Integrated Network Service Control Technology based on ALL-IP]

In recent years, as well as the mobile communication network, IEEE 802.11, wireless LAN network, Bluetooth network and related technologies are rapidly developed, the use of the wireless Internet is expanding. Accordingly, Mobile Internet Protocol (Mobile IP) technology is in the spotlight as one of the next generation technologies.

Mobile IP is a technology necessary to always ensure a connection even when a terminal having an IP address moves. Mobile IP supports mobility through a dual address system. That is, mobile IP has two address systems, a home address and a care of address.

The home address is an address that does not change to satisfy that once a session is established, it must maintain the same IP address for that set time. The COA is an address that varies according to the movement of the terminal to route to the moved region when the terminal moves. Therefore, the COA guarantees continuous internet service as the terminal moves and changes as the routing area changes.

On the other hand, such mobile IP technology has problems such as triangular routing problem, long waiting time and bottleneck. In order to solve this problem, a mobility control structure has been proposed that distributes functions necessary for mobility control, that is, location management and handover management. However, due to the inherent characteristics of such a distributed structure, an additional control signal is required, resulting in a buffering phenomenon and a latency time.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problem, and an object thereof is to reduce the buffering phenomenon and the waiting time generated in the distributed mobility control structure.

In addition, it aims to improve the inefficiency of data transmission in a distributed network.

It is also an object to reduce the number of forwarding entries for data transfer to a mobile terminal maintained at a router.

The above technical problem may include receiving a received data transmission request, identifying a home address group to which the terminal belongs, and adding a tunnel header to data to be transmitted using forwarding information for the home address group to which the terminal belongs; And transmitting the data to which the tunnel header is added to at least one network access device including a network access device to which the receiving terminal belongs.

According to the present invention, the buffering phenomenon and the delay time generated in the network in which the handover control and the mobility control are distributed can be reduced, so that data transmission can be made faster.

In addition, it is possible to provide a distributed execution of the router function of the transmitting side can eliminate the bottleneck that can occur during data transmission, and can increase the efficiency of network resource management.

In addition, network resources can be saved by reducing the number of forwarding entries for data transfer.

The foregoing and further aspects of the present invention will become more apparent through the preferred embodiments described with reference to the accompanying drawings. Hereinafter, the present invention will be described in detail so that those skilled in the art can easily understand and reproduce the present invention through these embodiments.

1 is an exemplary diagram of a mobility control architecture network according to a preferred embodiment of the present invention.

As shown in FIG. 1, a plurality of heterogeneous access networks (access network a, access network b, ...) are connected around the core network. The core network includes a location management server 10, and the access network includes a wired / wireless modem, a base station, and terminals according to each type of access network. In addition, there are network connection devices, that is, routers 20a, 20b, ..., between the access network and the core network.

The terminal may be a fixed terminal or a mobile terminal. In the present embodiment, the mobile terminal uses a home address IP assigned to the mobile terminal instead of a local IP address used in the access network. .

Since the terminal does not use the IP address used in the moved access network even after the movement, the location management server 10 maintains information of the router to which the mobile terminal is currently connected for data transfer between terminals. The information on the router to which the mobile terminal is currently connected is used to create an IP tunnel between the router to which the transmitting terminal is connected and the router to which the receiving terminal is connected during data transfer between the terminals.

However, when a query does not occur from the router to the location management server 10, that is, when the data is not transmitted from one terminal to another mobile terminal, the information of the router to which the mobile terminal maintained in the location management server is connected. Is not forwarded to any router.

Referring to the data flow in the mobility control architecture network shown in FIG. 1, the transmitting terminal 30c first transmits data to be transmitted to an adjacent router 20c. At this time, when the transmitting terminal 30c is a mobile terminal, the destination address of the transmission data is the home address of the receiving terminal 30e. The router 20c receiving the data generates an IP tunnel t with the router 20e to which the receiving terminal 30e is connected when it holds the forwarding entry information for the receiving terminal 30e. Tunneled data is transmitted through the generated tunnel t. On the other hand, when the router 20c adjacent to the transmitting terminal 30c does not have a forwarding entry for the receiving terminal 30e, it queries the location management server 10 for information about the router to which the receiving terminal 30e is connected. do. The IP tunnel t is generated based on the information obtained in response to the query. In addition, the tunnel header for the generated IP tunnel through the generated tunnel may transmit (Tunnelled data).

In this case, the forwarding entry includes information necessary for data forwarding, such as a destination IPv6 address, a prefix length, information related to switching and quality of service (Qos) configuration, and the like.

Hereinafter, referring to FIG. 2, a data transmission process will be described in more detail when a forwarding entry does not exist in the router 20c of the transmitting terminal 30c.

2 is a structural diagram of a data transmission system according to an exemplary embodiment of the present invention.

The location management server 10 has not only router information to which a terminal is connected, but also router information to which terminals belonging to a home address group to which the terminal belongs are connected. In this case, the home address group may be configured by a policy of an operator, and may be, for example, an IP subnet. This information is passed to at least one other router. Hereinafter, routers for linkage between the access network and the core network are referred to as end routers 20c, 20e, and 20f, and routers existing in the core network for linkage between the end routers are referred to as core routers 25.

Specifically, when a mobile terminal is initially connected or a connected router is changed due to a handover, the mobile terminal is delivered to all the routers to which the mobile terminal is accessible and the core router supporting the home address group method. The conveyed information is then used for generating forwarding entries for terminals belonging to the home address group.

Here, the router to which the mobile terminal can be connected may be end routers 20c, 20e, and 20f of access networks that may exist in a periphery to which the terminal may be accessed by performing a handover or the like.

2, the transmitting terminal 30c transmits data to an adjacent router, that is, an end router 20c in which it is registered. At this time, when the receiving terminal 30e is a mobile terminal, the destination address of the transmission data is the home address of the receiving terminal 30e.

The edge router 20c, which has received data from the transmitting terminal 30c, holds the forwarding entry information for the receiving terminal 30e, as described above. 20e) and create an IP tunnel. Then, the tunnel header is added (Tunnelled data) through the generated IP tunnel.

On the other hand, the transmitting terminal side terminating router 20c which has received data from the transmitting terminal 30c queries the location management server 10 for information on the router to which the receiving terminal 30c is connected when there is no forwarding entry. . And, it is possible to obtain information of the terminating router 20e to which the receiving terminal 30c is connected. However, a delay time of data transmission occurs while the receiving terminal 30c queries the location management server 10 for the connected router information and receives a response.

Therefore, according to a characteristic aspect of the present invention, the transmitting terminal side end router 20c queries the location management server 10 for the receiving router information, and simultaneously grasps the router information belonging to the same home address group as the receiving terminal. . Then, the forwarding entry information for the home address group can be known. That is, even if the receiving terminal does not know the terminal router 20c to which it is connected, the forwarding entry information of the home address group to which the receiving terminal belongs may be known.

Then, while querying the location management server 10 for information on the receiving router, it generates a data transmission tunnel for the IP or the IP upper layer according to the information, and transmits the tunneled data with the tunnel header added thereto.

The transmitting terminal side terminating router 20c includes a first tunnel header including address information of a core network connection device in data at the time of tunneling, and a second tunnel header including a multicast transmission address including the at least one destination address. Add That is, double tunneling data is generated.

The data is transmitted to the end routers 20e and 20f to which the terminals 30e and 30f belonging to the home address group including the receiving terminal 30e belong.

When the core network 25 exists in the core network, the core router 25 receives the data to which the first tunnel header is added and removes the first tunnel header. And at least one destination address of the second tunnel header is identified. The multicast address of the second tunnel header is identified, and data is replicated as many as the number of destination addresses to which the data is to be transmitted. For each of the replicated data, a tunnel header including address information of the receiving end routers 20e and 20f and a tunnel header including address information of the receiving terminal are added. That is, the core router receiving the data including the two tunnel headers transmits the two tunnel headers including the duplicated data.

The replicated data is then forwarded to the end routers 20e and 20f belonging to the home address group. At this time, each data is transmitted to the receiving end routers 20e and 20f in a unicast manner.

That is, according to this aspect, in the transmitting router 20c, the terminal of the home address group to which the receiving terminal 30e belongs before obtaining information from the location management server 10 to the terminating router 20e to which the receiving terminal 30e belongs. Send data to routers 20e and 20f. Since the terminating router 20c to which the transmitting terminal belongs has its own home address group information to which the transmitting terminal belongs, information on the terminating routers 20e and 20f to which the terminals 30e and 30f belonging to the home address group belong. I can figure it out quickly.

The terminating router 20e of the receiving end receiving the data to which the two tunnel headers are added removes the tunnel header which has set itself as the destination address, identifies the tunnel header having the destination address specified in the data, and receives the receiving terminal 30e. ) Transmits data to the terminal when the connection is established. On the other hand, the terminating router 20f to which the receiving terminal 30e having the designated destination address is not connected does not transmit data.

Accordingly, while the transmitting router 20c grasps the information of the network connection device 20e to which the receiving terminal 30e belongs from the location management server 10, it is possible to transmit data to the receiving terminal 30e so that the correct position can be obtained. Eliminate delays incurred for identification.

After that, when the transmitting terminal 30c receives the query result from the connected router 20c to the location management server 10, the forwarding entry for the receiving terminal 30e is added based on the received information. Thereafter, the data received from the transmitting terminal 30c can use the forwarding entry for the additional receiving terminal 30e. Thereafter, the router 20c to which the transmitting terminal 30c is connected can transfer data in the same manner as when the router 20c holds the forwarding entry information for the receiving terminal 30e.

3 is a flowchart illustrating a data transmission method according to an embodiment of the present invention.

First, a registration process of a terminal will be described with reference to FIG. 3.

When the power is newly applied or when the terminal is moved and the handover is performed as the location is changed, the terminal 30-2 registers with the adjacent end router 20-2 (S300). Then, the end router 20-2 receiving the registration request from the terminal 30-2 transmits it to the location management server 10 to update the location information of the terminal 30-2 (S310).

The location management server 10 updates location information on the newly registered terminal 30-2 according to the received information (S312).

4 is a location information table for a home address of a terminal, and FIG. 5 is a location information table for a home address group of a terminal.

As shown in FIG. 4, the location management server 10 manages home addresses of terminals and IP addresses of end routers to which respective terminals are connected. In addition, as shown in FIG. 5, the location management server 10 manages an IP address of an end router or a core router for a home address group.

That is, when the location management server 10 receives the newly registered terminal information from the terminal router 20-2, the location management server 10 receives the information of the terminal router 20-2 to which the newly registered terminal 30-2 is connected, and The information on the router to which the home address group belonging to the terminal is connected is updated.

In addition, all terminal routers that can be connected to the terminal, and delivers to the core router 25 (S314, S316). The terminal routers 20-1 receiving the updated information update the forwarding entry for the home address group based on the transmitted information (S320).

Accordingly, when the terminal 30-2 is newly registered with the terminating router 20-2, the location change of the terminal 30-2 at the location management server 10, the core router 25, and other terminal routers is changed. It is possible to update the information according to.

Hereinafter, a data transmission method in the case where a core router exists in the core network will be described in detail with reference to FIG. 3.

First, the transmitting terminal 30-1 transmits data to an adjacent transmitting end router 20-1 (S330).

At this time, when the transmitting terminal 30-1 is a mobile terminal, the destination address of the transmission data is the home address of the receiving terminal 30-2. The transmitting end router 20-1 receiving the data grasps the forwarding entry information for the receiving terminal 30-2.

6 is a forwarding entry information table for a data destination address.

That is, the transmitting end routers 20-1 each hold a forwarding entry information table for the destination address, as shown in FIG. As described above, the forwarding entry information may include, for example, information necessary for data forwarding such as a destination IPv6 address, a prefix length, information related to switching and quality of service (Qos) configuration, and the like.

7 is a tunneling information table for a data destination address.

The transmission termination router 20-1 holds the tunneling information table necessary for generating tunneling, as shown in FIG. An IP tunnel may be formed with the destination address, that is, the receiving end router 20-2, according to the tunneling information table based on the forwarding entry information that is identified (S340). In this case, the double tunnel destination IP address is added as the first tunnel header as the core router of the core network and the tunnel destination IP for creating the tunnel, and is from the core router to the destination end router in which the home address group function is implemented. The second destination address for tunnel formation is included in the second tunnel header. As such, the double tunneling data may be generated based on the tunneling information table. Then, it can be delivered through the generated IP tunnel.

In this case, the data in which the double tunneling is formed is via the core router 25 existing in the core network. That is, the data to which the tunnel header is added is transmitted to the core router 25 (S345).

The core router 25 then removes the first tunnel header set as its destination and grasps the multicast address information added to the second tunnel header. In step S350, data is replicated as much as the number of destinations to be transmitted based on the multicast address information.

8 is a forward information table for the core router to refer to data replication.

That is, the core router 25 may copy the data according to the destination address of the data to be transmitted based on the stored forward information table. Also, based on the forward information table, the data is transmitted to an end router address to be transmitted next (S360).

The receiving end router 20-2 receiving the transmission data removes the tunnel header of the data to which the received tunnel header is added (S370). When the destination address of the data is identified, and the terminal corresponding to the destination address is connected, the data in which the tunnel header is removed is transmitted to the receiving terminal 30-2 (S380).

9 is a flowchart illustrating a data transmission method according to another embodiment of the present invention.

First, with reference to FIG. 9, a data transmission method will be described when the transmission termination router 20-1 does not hold information on the transmission terminal 30-1.

The transmitting terminal 30-1 transmits the transmission data to the adjacent transmitting end router 20-1 (S900). At this time, when there is no information on the terminating router connected to the receiving terminal 30-2, the transmitting terminating router 20-1 requests the location management server 10 for the position information on the receiving terminal 30-2. (S910). Then, the location management server 10 may provide the reception terminal router 20-2 to which the reception terminal 30-2 is connected (S915). The transmission end router 20-1 updates the forwarding entry information of the pre-stored home address group according to the location information of the reception terminal 30-2 received from the location management server 10 (S920). Then, a tunnel is established based on a forwarding entry for transmission data, and a tunnel header is added to the data (S930). Accordingly, data transmitted later to the corresponding reception terminal 30-2 may perform a fast data transmission process in the same manner as described above, that is, when the transmission termination router 20-1 holds the forwarding entry.

In this case, it is preferable that the transmitting end router 20-1 transmit the received receiving terminal information to other routers in the same way as it transmits to the other end router or the core router at the time of registration.

According to a characteristic aspect of the present invention, the transmitting end router 20-1 transmits the location information request to the location management server 10 (S910) and simultaneously identifies forwarding entry information of the home address group to which the target terminal belongs. Then, the forwarding entry information about the home address group is found, and an IP tunnel for an IP or an IP upper layer is generated (S940). Then, data is transmitted to the home address groups, that is, at least one end routers.

End routers receiving the data to which the tunnel header has been added remove the tunnel header (S950). Then, it may be determined whether the corresponding receiving terminal is a terminal connected to the self according to the destination address included in the received data. If it is determined that the receiving terminal is connected, data is transmitted to the terminal (S960).

On the other hand, the above-described data transmission method and the location management method of the terminal can be created by a computer program. The program may also be embodied by being stored in a computer readable media and being read and executed by a computer. The storage medium includes a magnetic recording medium, an optical recording medium and the like.

So far I looked at the preferred embodiments of the present invention. Those skilled in the art will appreciate that the present invention can be implemented in a modified form without departing from the essential features of the present invention. Therefore, the disclosed embodiments should be considered in descriptive sense only and not for purposes of limitation. The scope of the present invention is shown in the claims, and all differences within the scope equivalent thereto should be construed as being included in the present invention.

1 is an exemplary diagram of a mobility control architecture network according to a preferred embodiment of the present invention;

2 is a block diagram of a data transmission system according to an embodiment of the present invention;

3 is a flowchart illustrating a data transmission method according to an embodiment of the present invention;

4 is a location information table for a home address of a terminal;

5 is a location information table for a home address group of a terminal;

6 is a forwarding entry information table for a data destination address;

7 is a tunneling information table for a data destination address,

8 is a forward information table for the core router to refer to data replication;

9 is a flowchart illustrating a data transmission method according to another embodiment of the present invention.

Claims (9)

A data transmission method in a network in which mobility control and handover control of a terminal are distributed, Receiving a data transmission request, identifying a home address group to which the terminal belongs, and adding a tunnel header to data to be transmitted using forwarding information for the home address group to which the terminal belongs; And And transmitting the data to which the tunnel header is added, to at least one network access device including a network access device to which the receiving terminal belongs. The method of claim 1, Recognizing registration of the terminal; And Transmitting home address information of the registered terminal to a location management server, and receiving home address group information to which the terminal belongs in response. The method of claim 1, Receiving updated home address group information from a location management server; And And updating the forwarding information for the home address group information in accordance with the received information. The method of claim 1, Requesting network access device information to which the terminal is connected to a location management server to determine forwarding information of the terminal; Receiving network access device information to which the terminal is connected in response to the request for information; And And updating the forwarding information of the home address group to which the receiving terminal belongs, based on the received information. The method of claim 1, wherein after the transmitting step, Receiving, by the core network access device, the data added with the tunnel header; Identifying at least one destination address to which data to which the received tunnel header is added is to be transmitted; And And duplicating the data to which the tunnel header is added according to the determination result and transmitting the copied data to at least one network device according to the destination address. The method of claim 5, The data added with the tunnel header includes a first tunnel header including address information of the core network access device, and a second tunnel header including a multicast transmission address including the at least one destination address. Data transmission method. The method of claim 1, Removing the tunnel header of the data to which the received tunnel header has been added; And And transmitting the data from which the tunnel header has been removed, to a terminal having a destination address specified in the data. In the terminal location management method in a network in which mobility control and handover control of a terminal are distributed, Updating home address group information to which the terminal belongs by acquiring home address information of a registered terminal and information of a network connection apparatus in which the terminal is registered; And And transmitting the updated home address group information to at least one network access device. The method of claim 8, Receiving a network connection device information request to which a receiving terminal is connected from a network connection device to which a transmitting terminal is connected; And And transmitting the network connection device information to which the data receiving terminal is connected to the network connection device to which the transmitting terminal is connected to the access device information request.

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