JP2011010284A - Radio relay apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the following problem: conventional IEEE 802.16j and DF type relay systems arranging a relay apparatus between a base station and a terminal is not capable of arranging a local server directly under the relay apparatus as all traffics are transmitted to a user data terminal apparatus.SOLUTION: In a radio relay apparatus 11 including a terminal function unit 12 and a base station function unit 13, a local server access LSA function unit 21 to perform a processing corresponding to an upstream data destination or a downstream data sending source is included in the base station function unit 13, and a routing function unit 19 is included between the base station function unit 13 and the terminal function unit 12.

Description

  The present invention relates to a radio relay apparatus in a radio communication system in which a radio relay apparatus is arranged between a base station and a terminal.

In the present invention, a wireless access system based on IEEE 802.16e mobile WiMAX (Worldwide interoperability for Microwave Access), which is one of the broadband wireless access systems, is treated as background technology (Non-patent Document 1). However, the present invention is not limited to the mobile WiMAX system, but can be applied to Advanced WiMAX (IEEE 802.16m) and similar network configurations.

FIG. 19 shows a WiMAX relay system configuration of IEEE802.16j which is a WiMAX relay standard specification. The IEEE 802.16j relay station (16j relay station) 8 is arranged between the base station 6 and the terminal 9, and relays user traffic between the base station 6 and the terminal 9. The WiMAX communication system is classified into an ASN (Access Service Network) that manages connection with the WiMAX terminal 9 and a CSN (Connectivity Service Network) that provides an IP connection function. ASN is composed of user management device 4, user data termination device 3, base station 6 and relay station 8, and realizes connection of terminal 7 by base station 6 and relay connection of terminal 9 via 16j relay station 8. .

In the WiMAX communication system, user data from (to) the terminal 7 is transmitted through a GRE (Generic Routing Encapsulation) tunnel 10 constructed between the base station 6 and the user data terminating device 3 shown in FIG. Similarly, user data from (to) the terminal 9 is also transmitted through the GRE tunnel 10. This GRE tunnel is for specifying a communication path between specific devices, for example, between the base station 6 and the user data terminating device 3, and encapsulates by inserting routing information and an identifier in the GRE header. This is what is achieved. Therefore, in the WiMAX relay system, the server 2 that communicates with the terminal 7 and the terminal 9 is always arranged in the CSN (for example, Non-Patent Document 2).

The same applies to a DF (Decode Forward) type relay station (FIG. 21) having a terminal function unit and a base station function unit. In the DF type relay station 11, a GRE tunnel 14 is constructed between the base station function unit 13 of the relay station 11 and the user data terminator 15 of the ASN, and all the traffic from the user terminal passes through the GRE tunnel 14 to terminate the user data. Transmit to device 15. Therefore, even in this configuration, a server for data communication cannot be arranged in the ASN, and a server is arranged in the CSN.

IEEE P802.16j / D9 WiMAX Forum Network Architecture-Stage2-

In a broadband wireless relay system, since a plurality of terminals are connected to a relay station (relay device), there is a problem that a line capacity between the relay station and the base station becomes insufficient when the number of terminals connected to the relay station increases. . As a means for solving this problem, as shown in FIG. 22, a local server 16 is installed in a train, car, home, etc. where the relay station 11 is installed, and the terminal 9 in the train, car, home is connected to these local stations. Although it is considered effective to confine user traffic in the relay system (relay station 11 and local server 16) by accessing the server 16 and reduce the amount of relay line traffic, the current WiMAX relay system IEEE In the 802.16j and DF type relay systems, since all traffic is transmitted to the user data terminating device 3 via the GRE tunnel, there is a problem that a local server cannot be installed in the ASN.

Therefore, in the present invention, by providing a local server access function for connecting a local server to the relay station, a relay station system that enables local server access 17 and external server access 18 in the CSN at the same time is realized. With the goal.

  The present invention provides a wireless relay device including a base station function unit and a terminal function unit, and includes a local server access (LSA) function unit and a routing function unit between the base station function unit and the terminal function unit.

According to the present invention, there is an effect that high-speed data communication can be realized without using a relay line where terminals are congested.

1 is a diagram illustrating a configuration of a wireless communication system in a first embodiment. 6 is a diagram illustrating a configuration example of a relay station in Embodiment 1. FIG. FIG. 3 is a diagram showing a base station functional unit configuration in the first embodiment. 4 is a flowchart illustrating an example of UL data processing among the LSA functions according to the first embodiment. 4 is a flowchart illustrating an example of DL data processing in the LSA function according to the first embodiment. 6 is a diagram illustrating an operation example of a routing function unit in Embodiment 1. FIG. FIG. 10 is a diagram illustrating a configuration example of a wireless relay system in a second embodiment. 10 is a flowchart illustrating an example of UL data processing in the LSA function unit according to the second embodiment. 10 is a flowchart illustrating an example of DL data processing in the LSA function unit according to the second embodiment. It is a figure which shows the packet structure received by the LSA function part. FIG. 10 is a diagram illustrating an operation example of a routing function unit in the second embodiment. FIG. 10 is a diagram illustrating a configuration example of a wireless relay system in a third embodiment. 10 is a flowchart illustrating an example of processing of an LSA function unit according to Embodiment 3. FIG. 10 is a diagram illustrating another configuration example of the relay station in the third embodiment. FIG. 10 is a diagram illustrating a configuration of a relay station in a fourth embodiment. FIG. 10 is a diagram illustrating an example in which communication between a terminal and a local network, communication between a terminal and an external network, and communication between a local network and an external network is realized by the LSA function in the fourth embodiment. FIG. 10 is a diagram showing a sequence up to local network access in the fourth embodiment. 10 is a flowchart illustrating an example of UL data processing in the LSA function according to the fourth embodiment. It is a figure which shows the conventional WiMAX relay system structure. It is a figure which shows the GRE tunnel between the base station and user data termination | terminus apparatus in the conventional WiMAX relay system. It is a figure which shows the conventional DF type | mold relay station. It is a figure which shows the connection to the local server access and external server access which show the objective of this invention.

Embodiment 1 FIG.
In this embodiment, in a relay device including a terminal function unit and a base station function unit, a routing function unit is provided between the terminal device and the base station function unit, and further, CS (Convergence Sublayer) of the base station function unit is provided. An example in which access to a local server is realized by providing an LSA (Local Server Access) function will be described.

FIG. 1 is a diagram of a communication system to which a relay device described in the present embodiment is applied. FIG. 2 shows a block configuration of the relay device (relay station) of the present embodiment. The relay station 13 includes a terminal function unit 12 connected to the network wirelessly, a routing function unit 19, and a base station function unit 20 connected wirelessly to the terminal 9, and the base station function unit 20 includes the LSA function unit 21. It has. IP packet transmission is performed via the routing function unit 19 between the terminal function unit 12 and the base station function unit 20.

FIG. 3 shows details of the base station function unit 20. The base station function unit 20 includes a PHY layer 22 and a MAC layer 23 for realizing wireless data transmission / reception with a terminal, a control plane 24 for managing a terminal, and a CS (Convergence Sublayer) 25 serving as a network interface for user data. The LSA function unit 21 is arranged in the CS 25 and includes a destination determination unit 26 and a GRE processing unit 27. The destination determination unit 26 uses the local server IP address held in the LSA function unit to determine whether or not the address is for the local server, thereby performing routing between the base station function unit and the user data termination device. Determine the need for header processing. When accessing the local server 16, IP packet communication is performed, and when accessing the server 2 in the CSN, the GRE processing unit 27 performs GRE header assignment processing according to the instruction of the Control Plane 29.

4 and 5, GRE header assignment determination and assignment by the destination determination unit 26 and the GRE processing unit 27 of the LSA function unit when receiving uplink (Up Link: UL) data and when receiving downlink (Down Link: DL) data. The flow of processing is shown respectively.

When the LSA function unit 21 receives UL data (data transmitted from the terminal 9) from the MAC layer 23 of the base station function unit 20, the LSA function unit 21 performs the determination 29 based on the destination IP address in FIG. If the destination IP address is 32 addressed to the local server, it is transferred to the routing function unit without performing GRE processing. On the other hand, if the destination IP address is an address 33 other than the address addressed to the local server, a GRE header addressed to the user data terminating device 15 is added 30 and transferred 31 to the routing function unit.

When the LSA function unit 21 receives DL data (data addressed to the terminal 9) from the routing function unit 19, the LSA function unit 21 performs the source IP address determination process 35 of FIG. If the source IP address is (38) from the local server, the IP packet is transferred to the MAC layer as it is. On the other hand, if the source IP address is the user data terminating device 15, the GRE tunnel is terminated, the GRE header is deleted, the encapsulated internal IP packet is extracted, and transferred to the MAC layer.

This makes it possible for the LSA function unit to determine whether local server access or access to other destinations. For local server destinations, IP communication is performed without using the GRE tunnel. For CSN servers, communication using GRE tunnel can be realized.

In this example, the source IP address is used to determine DL data, but the protocol number (IP / GRE), destination IP address (addressed to terminal / base station) included in the IP header, Similarly, it is possible to determine whether the communication is directed to the local server or the CSN server.

Next, the detailed operation of the routing function unit 19 is shown in FIG. The routing function unit 19 performs packet routing to the terminal function unit 12, the local server 16, and the base station function unit 20 according to the destination IP address. User data 40 addressed to the local server 16 from the base station function unit 12 is transferred to the local server 16, and user data 41 addressed to the user data terminal device 3 is transferred to the terminal function unit 12. Control data 42 addressed to the user management device 4 from the base station function unit 20 is transferred to the terminal function unit 12. Here, the solid line in FIG. 6 indicates user data, and the dotted line indicates control data. Further, user data 43 addressed to the terminal 9 under the relay device 13 from the local server 16 and user data 44 addressed to the base station function unit 20 from the terminal function unit 12 are transferred to the base station function unit 20, and the terminal function unit 12 The control data addressed to the base station function unit 20 is also transferred to the base station function unit 20.

Thus, in this Embodiment 1, it was set as the structure which implement | achieves local server access by giving LSA function for accessing local server to CS of a base station function part. By accessing the local server, high-speed data communication can be realized without using a congested relay line. Also, by adding the LSA function to the base station function unit, it is possible to reduce the amount of header processing compared to the case where the base station function unit and the LSA function unit are separated.

Embodiment 2. FIG.
In the first embodiment, the LSA function for accessing the local server is arranged in the base station function unit. However, considering the versatility with the existing base station configuration, the present embodiment shows a configuration in which the LSA function unit and the base station function unit are separated. In a configuration in which the LSA function unit and the base station function unit are separated, a local server access is realized by providing a control information analysis unit in addition to the destination determination unit and the GRE processing unit. In this configuration, since the IP packet addressed to the local server and the IP packet addressed to the intra-CPE server are both transmitted to the LSA function unit via the GRE tunnel, the operation of the routing function unit is different from that of the first embodiment.

FIG. 7 shows a block diagram of the relay apparatus of this embodiment. The configuration of the communication system in which this relay station is used is the same as that in FIG. 1 described in the first embodiment. The relay station 13 includes an LSA function unit 49 including a terminal function unit 46, a base station function unit 48, a routing function unit 47, a control information analysis unit 49, a GRE processing unit 52, and a destination determination unit 53.

The control information analysis unit 51 analyzes the control sequence (Path_Reg_Req / Paht_Reg_Rsp) between the base station function unit 48 and the user management apparatus 4 associated with the network connection of the terminal under the relay station, and also assigns the DHCP IP address of the terminal under the relay station By analyzing the message, the terminal obtains the IP address of the terminal and the Data Path ID set as the GRE key, and maintains the relationship. Thus, even if the destination determination unit 53 and the GRE processing unit 52 of the LSA function unit 49 do not provide these information from the base station function unit 48, the control information analysis unit 51 of the LSA function unit 49 uses the terminal IP address. GRE header assignment determination and GRE header assignment using Data Path ID can be realized.

Here, the method of acquiring the data path ID and IP address information from the sequence between the base station function unit and the user management apparatus associated with the network connection of the terminal is shown, but the information is acquired from the user management apparatus and the base station. It is also possible to set with static parameters.

8 and 9 show the operations of the GRE processing function 52 and the destination determination function 53 when receiving UL data and DL data.
The base station function unit 48 is set to transmit all UL data to the LSA function unit 49. The packets received by the LSA function unit 49 from the base station function unit 48 via the routing function unit 47 are subjected to encapsulation shown in FIG. 10, and the user data is encapsulated with an external IP address and a GRE header. . On the other hand, control data between the base station function unit 48 and the user management device 4 is transmitted without being encapsulated as IP data.

When the LSA function unit 49 receives UL user data or UL / DL control data from the routing function unit 47, the LSA function unit 49 uses the internal IP header of FIG. If the internal destination IP address of the UL user data is 58 for the local server held by the LSA function unit 49, terminate the GRE tunnel, remove the GRE header and external IP header, and send it to the routing function unit as an internal IP packet. Forward. On the other hand, if the internal destination IP address of UL user data is an address 59 other than the one addressed to the local server, the destination address in the external IP header is reassigned from the LSA function unit 49 to the user data terminator 56 and transferred to the routing function unit To do. The same applies to UL / DL control data. In addition, since DL user data from the CSN server is directly transferred to the base station function unit 48 by the routing function unit, the LSA function unit 49 receives the DL user data from the routing function unit 47 and receives the DL user data from the local server. The packet is determined to be an IP packet, and a GRE header and an external IP header are added according to the processing flow of FIG. At this time, the Data Path ID is specified and set in the GRE Key from the terminal IP address under the relay station serving as the destination acquired by the control information analysis unit 51.

This makes it possible for the LSA function unit to determine whether local server access or access to other destinations. For local server destinations, IP communication is performed without using the GRE tunnel. For CSN servers, communication using GRE tunnel can be realized.

The routing function unit 47 realizes packet routing to the terminal function unit 46, the base station function unit 48, the LSA function unit 49, and the local server 50 according to the destination IP address. FIG. 11 shows the detailed operation of the routing function unit in this embodiment. The routing function unit 47 transfers the user data 63 addressed to the LSA function unit from the base station function unit 48 to the LSA function unit. Also, the user data 66 addressed to the local server is transferred from the LSA function unit to the local server, and the user data 67 addressed to the user data termination device 15 is transferred to the terminal function unit. Further, the control data 64 addressed to the LSA function unit 49 is transferred from the base station function unit 48 to the LSA function unit, and the control data 68 addressed to the user management apparatus 4 is transferred from the LSA function unit to the terminal function unit. Also, user data 70 addressed to the base station function unit from the terminal function unit, user data 65 addressed to the base station function unit from the LSA function unit, and control data 71 addressed to the base station function unit from the terminal function unit are transferred to the base station function unit. Forward.

Thus, in this Embodiment, it was set as the structure which can use a general purpose base station for a relay station by isolate | separating a base station function part and a LSA function part. In order to separate the LSA functions, a network connection sequence analysis function and a GRE processing function are required. By adopting a configuration in which a general-purpose base station can be used in the base station function unit of the relay station, it becomes possible to easily develop a relay station that realizes local server access.

Embodiment 3 FIG.
In the second embodiment, the configuration in which the routing function unit and the LSA function unit are separated as shown in FIG. 7 is shown. However, in the third embodiment, the routing function unit 47 and the LSA function unit 49 in the second embodiment are used. Is a new LSA function unit 71 shown in FIG.

The LSA function unit performs packet processing and packet transfer according to the destination IP address of the received packet. FIG. 13 shows an operation example of the LSA function unit 71 in the present embodiment.

In the LSA function unit 71, after receiving the packet, the protocol determination 74 is performed. If the protocol is GRE75, it is determined as user data, and internal destination IP address determination 77 is performed. If the internal destination IP address is 79 addressed to the terminal, it is determined as DL user data and transferred to the base station function unit as a GRE packet. If it is 80 addressed to the local server, it is determined as UL user data to the local server, GRE header termination processing 82 is performed, and transfer 83 is performed to the local server. If it is other destination IP address 78, it is determined as UL user data and transferred 81 to the terminal function unit as a GRE packet.

On the other hand, when the protocol is IP76, it is determined as user data or control data from the local server, and destination IP address determination 85 is performed. If it is addressed to the terminal 87, it is determined as user data from the local server, GRE header construction processing 89 is performed, and transfer 90 is performed to the base station function unit. If the destination IP address is 86 for the base station function unit, it is determined as control data for the base station, and is transferred 90 to the base station function unit as it is. If the destination IP address is 88 for the user management device, it is determined as control data for the user management device and transferred 91 to the terminal function unit.

As described above, in this embodiment, it is possible to realize local server access with a simple relay station configuration by using the routing function and the LSA function as one function.

The device configuration is not limited to the configuration shown in the above embodiment. For example, as shown in FIG. 14A, two interfaces of the LSA function unit are provided, and the local server and the terminal function unit are provided. It is also possible to connect with a network device such as a switching hub or a router. In this configuration, the routing function of the LSA function unit can be determined as reception port determination instead of IP address determination.

Furthermore, as a high-speed data communication via the relay station, not only a local server but also a network can be connected. An example of the configuration is shown in FIG. However, if the network address to be connected is different, a NAT (Network Address Translation) function such as a router is required.

In Embodiments 1 to 3 described above, it is assumed that each functional unit of the relay station is IP-connected, but even when these devices are connected by a bus or other interface The local server access by the LSA function can be realized, and the interface standard is not limited. However, when using another interface, it is necessary to devise such as changing the destination determination to an identifier that matches the interface.

Embodiment 4 FIG.
In the first to third embodiments described above, when the LSA function unit detects IP packets destined for the local server or originating from the local server by means such as destination IP address determination and internal destination IP address determination, all of them are detected. , To the appropriate destination (UL data to the local server, DL data to the terminal). In this embodiment, a user who accesses a local network configured by a private address is authenticated, and only an authorized terminal transfers data to the local network, and an example of CSN connection of a device in the local network Show.

  The configuration and operation will be described below using the configuration of the third embodiment shown in FIG. Even if the configuration of the first embodiment or the second embodiment is used, the same configuration is possible.

  As shown in FIG. 15, the LSA function unit 71 of the relay station 100 in this embodiment includes a DNS proxy response function unit 101. In the DNS proxy response function unit 101, the IP address of the authentication server for local network access is registered. Further, the LSA function unit has a function of determining whether or not the terminal is a permitted terminal by having a terminal state management function unit in addition to the function of determining whether the UL user data from the terminal is destined for the local network. The determination material may be an IP address or terminal specific information such as SFID or MAC address. Furthermore, since the LSA function unit has an address conversion function, it converts a private address and a global address when accessing the external network from the local network. When an authentication server or a device in the local network sends data to the terminal, ARP is sent to resolve the MAC address of the terminal. The LSA function unit has an ARP proxy response function unit, responds to this ARP as a proxy for the terminal, and transfers received data to the terminal.

  The network configuration of this embodiment is shown in FIG. The operation is shown using the sequence up to local network access in FIG. The terminal sends a DNS message to access the authentication server. The DNS proxy response function unit of the LSA function unit analyzes the DNS message and returns the IP address of the authentication server as a proxy if the domain name is the authentication server. After obtaining the IP address of the authentication server, the terminal accesses the authentication server and receives authentication. After authenticating the terminal, the authentication server notifies the LSA function unit of the authentication result for the terminal using a message. The LSA function unit refers to this message and shifts the state of the terminal in the state management function unit. However, it is not essential to use an authentication server, and it is possible to change the state of the terminal statically. When the LSA function unit receives UL user data from the terminal, the destination determination unit determines the destination IP address. If it is addressed to a global address, transfer it to the CSN server. If it is a private address, the terminal status is confirmed by inquiring the source IP address to the status management function unit. If the terminal is in the local network access permitted state, data is transferred to the local network, and if it is in the prohibited state, the packet is discarded. A flow chart of these LSA routing operations is shown in FIG. In this way, it is possible to divide the users into local network access permission groups and prohibition groups.

Here, the CSN connection of the devices in the local network will be described. A device in the local network can be connected to the CSN by using a terminal function unit. However, since each device has a private address, it cannot be directly connected to an external network. Therefore, the LSA function part converts to a global address by having the NAT or NAPT function which is an address conversion function. If the LSA function unit has a global IP address, the address used at this time is used, and if not, the address held by the terminal function unit is used. In this case, the terminal function unit needs a function of transferring user data addressed to itself to the LSA function unit. With this LSA function unit having an address translation function, it is possible to construct a relay station capable of communication between a terminal and a local network, between a terminal and an external network, and between a local network and an external network as shown in FIG. It becomes.

As described above, in this embodiment, the LSA function includes a terminal state management function, an address translation function, and an ARP proxy response function, and by cooperating with the authentication server, the local network access of only the authorized terminal and the CSN can be performed from the local network. Allows access to In this embodiment, access to the local network is restricted, but access to an external network or the like can also be restricted.

  As described above, the present invention can be applied to a relay station in a wireless communication system.

1 network, 2 server, 3 user data termination device, 4 user management device, 5 network, 6 base station, 7 terminal, 12 terminal function unit, 13 relay station, 16 local server, 19 routing function unit, 20 base station function unit , 21 LSA function unit, 22 PHY Layer, 23 MAC Layer, 24 Control Plane, 25 Convergence Sublayer, 26 Destination determination unit, 27 GRE processing unit, 46 Terminal function unit, 47 Routing function unit, 48 Base station function unit, 49 LSA Function unit, 50 local server, 51 control information analysis unit, 52 GRE processing unit, 53 destination determination unit, 70 terminal function unit, 71 LSA function unit, 72 base station function unit, 73 local server, 100 relay station, 101 DNS proxy Meet Function unit.

Claims (7)

In a wireless relay device composed of a terminal function unit and a base station function unit,
The base station function unit includes a packet destination determination unit, an LSA (Local Server Access) function unit including a GRE processing unit, and a routing function unit between the base station function unit and the terminal function unit. Wireless relay device. The wireless relay device according to claim 1,
Has a setting and storage function to hold the local server address in the LSA, and also has a function to acquire and store GRE Key information for the GRE tunnel for user data transfer from the base station function unit By using the destination address or the source address of the received packet, it is determined whether it is a transfer process for local server access or other, and the GRE header process is performed according to the destination. Relay device. In a wireless relay device composed of a terminal function unit and a base station function unit,
A wireless relay device that realizes communication to a local server by including an LSA (Local Server Access) function unit including a control information analysis unit and a GRE processing unit and a routing function unit between a terminal function unit and a base station function unit. The wireless relay device according to claim 3,
The GSA Key information for the GRE tunnel for user data transfer is acquired by analyzing the control sequence between the base station function unit of the relay device and the user management device in the ASN at the control information analysis unit of the LSA function unit A wireless relay device characterized by that. In the wireless relay device according to claim 3 or 4,
The destination address of the received packet using the GRE Key information for user data transfer that has the setting and storage function to hold the local server address in the LSA and acquired by the control information analysis unit of the LSA function unit Alternatively, a wireless relay device that determines whether a transfer process for local server access is performed using a transmission source address or not, and performs a GRE header process according to a destination. In the wireless relay device arranged between the base station and the terminal,
A routing function unit is provided between a base station function unit which is a base station side interface and a terminal function unit which is a terminal side interface, and the routing function unit has a predetermined information processing function without going through the base station. A radio relay apparatus connected to a local server and transmitting the uplink transmission data to the local server or the base station according to a destination of the uplink transmission data transmitted by the terminal. The wireless relay device according to any one of claims 1 to 5, wherein the LSA function unit includes a DNS proxy response function unit, a terminal state management function unit, an address translation function unit, and an ARP proxy response function unit. A relay device characterized in that a network that can be accessed by a terminal can be restricted by identifying the terminal and performing group management.

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