JP4865378B2 - Information transfer device - Google Patents

Description

  The present invention relates to an information transmission apparatus for transferring information between a backbone communication network and a plurality of radio base stations.

  An information transfer apparatus that transfers information between a backbone communication network and a plurality of radio base stations is known (Patent Document 1). As a configuration for connecting a plurality of radio base stations to the information transfer apparatus, in addition to a configuration for connecting a plurality of radio base stations from one communication port via a hub, a radio base station is connected for each communication port. The configuration is known (Patent Documents 2 and 3). As an application field of such an information transfer apparatus, there is a broadband wireless access technology, and research on WiMAX based on IEEE802.16 is being actively performed (Non-patent Document 1).

JP 2004-015435 A JP 2005-094336 A JP 2004-164576 A Takashi Tono, “WiMAX to Create the Wireless Broadband Era”, Impress, First Edition (December 1, 2005)

  When a plurality of radio base stations are connected to the information transfer apparatus via a hub as in the configuration described in Patent Document 1, the information transfer apparatus is identical to all the radio base stations connected to the hub. Information is transferred. In addition, the same information may be transmitted from all radio base stations, and communication resources cannot be used effectively. As described above, when communication resources are used inefficiently, it becomes difficult to secure communication resources necessary for guaranteeing the quality of communication services.

  On the other hand, in the configuration in which a plurality of wireless base stations are connected to a plurality of communication ports as in the configuration described in Patent Document 2, different subnetwork addresses are set for each communication port. It is not transferred to the radio base station, and it becomes easy to secure communication resources necessary for guaranteeing the quality of the communication service. However, if a different subnetwork address is set for each communication port as described above, when a wireless terminal station performs handover between wireless base stations, processing such as reassignment of an IP address is required. Reduce station mobility. Also, setting different subnetwork addresses for each communication port is not preferable from the viewpoint of effective use of address resources.

  An object of the present invention is to provide an information transfer apparatus in which mobility of a wireless terminal station is ensured while securing communication resources necessary for quality assurance of services.

The present invention relates to a core communication port connected to a core communication network, an IP address including a common network address and an individual host address, and a port number respectively assigned to a plurality of base stations connected to a plurality of radio base stations. a communication port, said the MAC address uniquely assigned to the radio terminal station communicating with the radio base station, the assigned in common to a plurality of communication ports Netw network address and before quinic and including IP address host address assigned individually for each line terminal station, and correspondence information generation means for generating association information that associates a pre SL port number, packet information received from the backbone network from with identifying the IP address of the wireless terminal station as a destination of the packet information, pair the correspondence information to the identified IP address Tagged transmitted the packet information only to the communication port of port number, and a data transfer means for transferring the packet data only to the radio base station connected to the communication port, wherein the correspondence information , Including a quality assurance parameter associated with the IP address, wherein the information transfer means transfers the packet information received from the backbone communication network at a transfer rate based on the quality assurance parameter .

In the present invention, it is preferable that the quality assurance parameter is determined based on a communication service in the wireless terminal station .

Further, in the present invention, the correspondence information generating means is configured so that when the wireless terminal station switches a wireless base station that transmits and receives packet information, the MAC address assigned to the wireless terminal station and the wireless terminal station newly The correspondence information is updated so that the port number assigned to the communication port to which the wireless base station that transmits and receives information is connected is associated with each other, and the information transfer means is configured so that the wireless terminal station newly transmits and receives information It is desirable to transfer data to a wireless base station at a speed that is faster than a transfer speed based on quality assurance parameters and that does not affect other communication traffic.

  ADVANTAGE OF THE INVENTION According to this invention, the information transfer apparatus with which the mobility of the radio | wireless terminal station was ensured, ensuring the communication resource required for the quality assurance of a service can be provided.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. FIG. 1 shows a communication system 102 including an information transfer apparatus 22 according to an embodiment of the present invention. The information transfer device 22 includes communication ports 28-0 to 28-n and includes a packet information transfer unit 31 and the like described later (n is the number of radio base station devices connected to the information transfer device 22). A positive integer). The information transfer device 22 is connected to the backbone communication network 12 via the communication line 28L-0, and transmits / receives information to / from other information transfer devices (not shown). The radio base station devices 24-1 to 24-n are connected to the communication ports 28-1 to 28-n via the communication lines 28L-1 to 28L-n, respectively. The radio base station devices 24-1 to 24-n form communication areas 30-1 to 30-n, and transmit and receive information to and from the radio terminal station devices 26-1 to 26-m (m is a radio). A positive integer indicating the number of terminal station devices).

  Mac addresses MacPx and MacP1 to MacPn, which are identification codes unique to hardware, are assigned to the communication ports 28-0 and 28-1 to 28-n. The wireless terminal station devices 26-1 to 26-m are assigned Mac addresses Mac1 to Macm, respectively.

  In addition to the MAC address, the communication ports 28-0 and 28-1 to 28-n are assigned port numbers Px and P1 to Pn, respectively. The port number is a number for identifying a communication port in processing executed by the information transfer apparatus, and is a number uniquely assigned in the information transfer apparatus 22.

  The radio base station apparatus 24-i (i is an integer from 1 to n) is connected to a predetermined radio terminal station apparatus among the radio terminal stations 26-1 to 26-m according to a predetermined radio communication protocol to which a Mac address is applied. Packet information is transmitted and received by wireless communication. As a wireless communication protocol, it is preferable to apply IEEE 802.16 or the like, but other wireless communication protocols (IEEE 802.11 or the like) may be used.

  FIG. 2 shows a configuration of the information transfer apparatus 22 according to the embodiment of the present invention. The packet information transfer unit 31 transfers the communication port (28-1 to 28) to be transferred based on the correspondence table 200 stored in the correspondence table storage unit 37 based on the information received by the packet information input / output processing unit 33-0 described later. -N)). The packet information input / output processing units 33-0 to 33-n are connected to the communication ports 28-0 to 28-n, respectively, and perform information input / output processing. The correspondence table generating unit 35, as will be described later, is a radio base station apparatus 24-1 to 24-n in which the MAC address Mac1-Macm of the radio terminal station apparatus 26-j and the radio terminal station apparatus 26-j transmit and receive information. Is generated (or updated) by associating the port numbers P1 to Pn assigned to the communication ports 28-1 to 28-n connected to the IP address "10.1.2.n". To do). The correspondence table storage unit 37 stores a correspondence table 200. The transfer information storage unit has a buffer memory for performing communication quality and traffic control assigned to each of the radio terminal station devices 26-1 to 26-m described later.

  Next, the operation of the communication system 102 configured by the information transfer apparatus 22 according to the present embodiment will be described. Between the wireless terminal station device 26-j (j is an integer of 1 to m) and at least one of the wireless base station devices 24-1 to 24-n, predetermined wireless communication is established before the wireless communication network is established. The following processing is executed according to the protocol.

  The wireless terminal station device 26-j performs preliminary wireless communication with the wireless base station device 24-i, and the wireless base station device 24-i is another wireless terminal different from the wireless terminal station device 26-j. The frequency of communication with the station apparatus 26-k (k is an integer of 1 to m different from j), the goodness of the propagation status of electromagnetic waves transmitted to and received from the radio base station apparatus 24-i, the radio base The communication goodness degree defined by the distance to the station device 24-i or the like is measured. Based on the communication goodness, the wireless base station devices 24-1 to 24-n that perform wireless communication are selected. The radio terminal station device 26-j transmits information including the Mac address Macj to the selected radio base station device 24-i. Then, the wireless base station device 24-i that has received the information recognizes the MAC address.

  Through such processing, the radio base station apparatus 24-i recognizes the Mac address Macj of the radio terminal station apparatus 26-j with which the radio base station apparatus 24-i communicates. For example, in the communication system 102 in FIG. 1, the radio base station device 24-1 recognizes Mac addresses Mac1, Mac3, and Mac7, and the radio base station device 24-2 recognizes Mac addresses Mac2, Mac6, and Mac8. The station device 24-n recognizes the Mac addresses Mac4, Mac5, and Macm. The radio base station devices 24-1 to 24-n transmit and receive packet information by radio communication with the radio terminal station device 26-j specified by the recognized Mac address Macj. A region where the wireless terminal station device 26-j can transmit and receive information to and from the wireless base station device 24-i is defined as a base station area 30-i. The MAC addresses Mac1 to Macm of the wireless terminal station devices 26-1 to 26-m recognized in this way are sent to the correspondence table generation unit 35 and used for generation (or update) of the correspondence table 200 as described later. .

  A unique IP address defined in the backbone communication network 12 is assigned to each of the communication ports 28-0 to 28-n. A common network address and different host addresses are assigned to the communication ports 28-1 to 28-n. In the information transfer apparatus 22 of FIG. 1, “10.1.3.3.1” is assigned to the communication port 28-0 as an IP address, and “10.2.1.2.1” is assigned to the communication ports 28-1 to 28-n. To "10.1.2.n" are assigned. However, the upper 24 bits of the IP address are the network address and the lower 8 bits are the host address.

  While the IP addresses of the communication ports 28-0 to 28-n are assigned in advance when the information transfer device 22 and the radio base station devices 24-1 to 24-n are installed, the radio terminal station devices 26-1 to 26-1 The IP address of 26-m is assigned later by the wireless terminal registration process described below, which is executed between the information transfer apparatus 22 and the wireless terminal station apparatuses 26-1 to 26-m.

  Next, registration of the wireless terminal device and generation of the correspondence table 200 will be described with reference to FIGS. 3 and 4. Here, a description will be given together with a specific example in which when the wireless base station device 24-1 newly recognizes the Mac address Mac1 of the wireless terminal station device 26-1, the IP address of the wireless terminal station device 26-1 is newly assigned.

  When the wireless base station device 24-i newly recognizes the Mac address Macj, the wireless base station device 24-i sends the connection notification packet information including the connection notification packet identifier in the header portion and the new Mac address Macj in the data portion to the communication line 28L-. i is transmitted to the information transfer device 22 via the communication port 28-i (S1). In the example of FIG. 1, connection notification packet information including a new Mac address Mac1 in the data portion is transmitted to the information transfer device 22 via the communication line 28L-1 and the communication port 28-1. The information transfer device 22 inputs the connection notification packet information sent in this way to the correspondence table generation unit 35 via the packet information input / output processing unit 33-1 and the packet information transfer unit 31.

  The information transfer device 22 determines an IP address corresponding to the extracted Mac address Macj (S3). The network address of the IP address determined here is the same as the common network address assigned to the communication ports 28-1 to 28-n. Further, the host address of the IP address to be determined is different from any of the host addresses assigned to the communication ports 28-1 to 28-n, and is already a wireless terminal station device 26- other than the wireless terminal station device 26-j. Assume that it is different from any of the host addresses already assigned to k. In the example of FIG. 1, the information transfer apparatus 22 determines that the IP address corresponding to the Mac address Mac1 is “10.1.2.n + 1”.

  In addition, when the wireless terminal station devices 26-1 to 26-m existing in the base station areas 30-1 to 30-n are constant, IP addresses are associated with the Mac addresses Mac1 to Macm in advance. The attached information may be stored in advance in storage means (not shown) of the information transfer device 22.

  The correspondence table generation unit 35 adds the contents of the correspondence table 200 stored in the correspondence table storage unit 37 to the determined IP address (S4). As shown in FIG. 4, the correspondence table 200 was included in the data portion of the determined IP address, the port number Pi of the communication port 28-i that was notified of the connection notification packet information, and the connection notification packet information. It is the table which matched Mac address Macj.

  In the address correspondence table 200 of FIG. 4, “10.1.2.n + 1” is determined as the IP address for the wireless terminal station device 26-1 having the Mac address Mac1, and the port number P1 of the communication port 28-1 is It is associated. Further, “10.1.2.n + 2” is determined as the IP address for the wireless terminal station device 26-2 having the Mac address Mac2, and the port number P2 of the communication port 28-2 is associated with the wireless terminal station device 26-2. Further, “10.1.2.n + 3” is determined as the IP address for the wireless terminal station device 26-3 having the Mac address Mac3, and the port number P1 of the communication port 28-1 is associated therewith.

  The correspondence table generation unit 35 includes the IP address determined for the Mac address Macj included in the data part of the connection notification packet information, the port number Pi of the communication port 28-i that has received the connection notification packet information, A correspondence table 200 in which the Mac address Macj included in the data portion of the connection notification packet information is associated is generated and stored in the correspondence table storage unit 37.

  As will be described later, the information transfer apparatus 22 receives information received from the backbone communication network 12 from a predetermined communication port (any one of 28-1 to 28-n) based on the correspondence table 200 (a predetermined radio base station apparatus ( By transmitting packet information Pck only to any one of 24-1 to 24-n), communication resources necessary for service quality assurance are ensured. In the correspondence table 200, quality IDs (communication speeds) are associated with the Mac addresses Mac1 to Macm of the wireless terminal station devices 26-1 to 26-m. The quality ID may be associated with the Mac addresses Mac1 to Mac3 in advance, or may be set in response to a request from the wireless terminal station devices 26-1 to 26-m. By setting the quality ID in this way and controlling communication traffic, which will be described later, it is possible to guarantee the communication quality in services (such as audio distribution and video distribution) that require real-time playback with severe data loss and transfer delay. it can.

  When the information transfer device 22 updates the address correspondence table 200, the header portion includes the address assignment packet identifier, the data portion includes the Mac address Mac1, and the IP address “10.1.2.n + 1” corresponding to the Mac address Mac1. Then, the address assignment packet information including the Mac address MacP1 of the communication port 28-1 is transmitted to the radio base station apparatus 24-1 via the communication port 28-1 and the communication line 28L-1 (S5).

  If the radio base station apparatus 24-1 determines that the header information included in the received packet information includes the address assignment packet identifier, it extracts the Mac address Macj, the IP address, and the Mac address MacPi from the data part. Then, the packet information including the IP address and the Mac address MacPi is transmitted to the wireless terminal station device 26-1 having the Mac address Macj (S6). The wireless terminal station device 26-1 extracts and stores the IP address and Mac address MacPi from the received packet information (S7).

  The process in which the wireless terminal station device 26-1 obtains the Mac address MacP1 from the information transfer device 22 can also be performed by a widely known ARP (Address Resolution Protocol).

  In the above description, the wireless terminal registration process is started when the wireless base station apparatus 24-1 recognizes the new Mac address Mac1, but the wireless terminal unregistered process is started at a predetermined time interval. It is good also as a structure.

  According to such wireless terminal unregistered processing, the same network address as the common network address assigned to the communication ports 28-1 to 28-n is assigned to the wireless terminal station devices 26-1 to 26-m. Assigned. Further, different host addresses from the host addresses assigned to the communication ports 28-1 to 28-n are assigned to the wireless terminal devices 26-1 to 26-m, respectively. Also, the wireless communication terminals 26-1 to 26-m can acquire and store the Mac address Pi of the communication port 28-i to which the wireless base station device 24-i that transmits / receives information to / from itself is connected. Become. Therefore, when the radio terminal stations 26-1 to 26-m switch the radio base stations 24-1 to 24-n that transmit and receive information (that is, handover), the information transfer apparatus 22 responds by the processing as described above. It is only necessary to update the table 200, and there is no need to reassign IP addresses to the wireless terminal station devices 26-1 to 26-m. For this reason, the mobility of the radio | wireless terminal station apparatuses 26-1 to 26-m can be ensured.

  Next, a process in which the information transmission apparatus 22 transfers information between the backbone communication network 12 and the radio base station apparatuses 24-1 to 24-n will be described. Here, it is assumed that IP addresses have already been assigned to the wireless terminal station devices 26-1 to 26-m by the wireless terminal registration process. Also, the wireless terminal station devices 26-1 to 26-m acquire the Mac address Pi of the communication port 28-i to which the wireless base station device 24-i that transmits and receives information to and from itself is connected by wireless terminal registration processing. And remember it.

  The packet information transfer unit 31 of the information transfer device 22 receives the packet information Pck from the backbone communication network 12 via the packet information input / output processing unit 33-0 connected to the communication port 28-0. The packet information transfer unit 31 identifies the IP address of the wireless terminal station device 26-j that is the destination of the packet information Pck from the header included in the received packet information Pck.

  Next, the packet information transfer unit 31 is associated with the IP address of the wireless terminal station device 26-j that is the destination identified from the packet information Pck described above from the correspondence table 200 stored in the correspondence table storage unit 37. The specified port numbers P1 to Pn are identified and acquired. As will be described later, the packet information Pck described above is transmitted only to the radio base station apparatus 24-i connected to any one of the specified port numbers P1 to Pn. As a result, it is possible to prevent (identical) packet information Pck from being transmitted from all the radio base station apparatuses 24-i to all the communication areas 30-1 to 30-n, and to provide communication resources for guaranteeing service quality. It becomes easy to secure.

  Further, the packet information Pck in which the port numbers P1 to Pn are specified in this way is stored in the transfer information storage unit 39. In the transfer information storage unit 39, packet information Pck is stored in a FIFO buffer assigned to each wireless terminal station device 26-j. The packet information Pck is stored as a transmission queue based on the quality ID described above. The packet information Pck stored in the transfer information storage unit 39 is sent from any of the packet information input / output processing units 33-1 to 33-n (corresponding port numbers P1 to Pn) at a predetermined timing based on the transmission queue described above. Is transmitted (for example, transmitted via the communication port 28-1).

  The radio base station device 24-1 receives the packet information Pck from the information transfer device 22, converts it into a radio signal, and transmits it. The wireless terminal station device 26-j determines that the packet information Pck is addressed to itself based on the setting of the destination address of the received packet information PckL, and acquires the packet information Pck.

  As described above, only the radio base station apparatus 24-1 connected to the communication port 28-1 having the port number P1 corresponding to the IP address identified from the header included in the packet information Pck in the correspondence table 200 described above is described above. By transmitting the packet information Pck, it is possible to prevent (identical) packet information Pck from being transmitted to all the communication areas 30-1 to 30-n and to secure communication resources for guaranteeing service quality. It becomes easy. Further, as described above, even if communication traffic increases in a burst manner by other wireless terminal stations when performing stream delivery or the like that requires continuous delivery of information such as audio and video, the packet information Pck Since communication traffic is controlled by the transmission queue at the transmission timing, a predetermined communication resource can be secured. Note that a best-effort communication service may be mixed in the configuration for guaranteeing the communication band as described above. For example, a configuration may be adopted in which a communication band for ensuring communication quality allocated to each of the wireless terminal station devices 26-1 to 26-m and a communication band for performing a best effort type communication service are allocated.

  Furthermore, as described above, the radio base station devices 24-1 to 24-n form the same subnetwork. For this reason, at the time of handover in which the radio terminal station 26-j switches the radio base station devices 24-1 to 24-n that transmit and receive information, the port corresponding to the new radio base station on the correspondence table 200 by the radio terminal registration process described above. It is only necessary to update the number, and there is no need to reassign the IP address. For this reason, the mobility of the wireless terminal station 26-j is not reduced.

  Further, when performing the handover as described above, the information transfer apparatus 22 uses the transfer rate based on the quality assurance parameters to the radio base station apparatus 24-n to which the radio terminal station apparatus 26-j newly transmits and receives information. Alternatively, the packet information Pck may be transferred at a high speed (temporarily within a range not affecting other traffic). Thereby, the packet information Pck that could not be sent at the time of handover can be sent to the wireless terminal station 26-j, and the communication quality as described above can be ensured.

  The transfer information storage unit 39 allocates a FIFO buffer for each communication service (service flow) in the wireless terminal station device 26-j, and stores packet information Pck (and transmission queue) transmitted for each service flow. May be. In this case, the quality ID in the correspondence table 200 described above may be associated with a plurality of service flows used by the wireless terminal device 26-j in addition to the Mac addresses Mac1 to Macm of the wireless terminal device 26-j. For example, the packet information transfer unit 31 may identify the service flow based on the TCP header of the packet information Pck from the packet information Pck.

  Furthermore, in the communication system 102, the same network address as the common network address assigned to the communication ports 28-1 to 28-n is assigned to the wireless terminal station devices 26-1 to 26-m. Even if the number of terminals connected to each base station varies, the network address is not consumed inefficiently, and the IP address can be effectively used. Accordingly, the shape of the service area can be set flexibly.

  In the wireless terminal registration process described above, the process for obtaining the IP address of the terminal can be executed by applying a widely known DHCP (Dynamic Host Configuration Protocol) server. By applying the DHCP server, the information transfer device 22 can be easily configured, so that the design and manufacturing cost of the information transfer device 22 can be reduced.

It is a figure which shows the communication system comprised by the information transfer apparatus which concerns on embodiment of this invention. It is a figure which shows the structure of the information transfer apparatus which concerns on embodiment of this invention. It is a figure explaining the radio | wireless terminal registration process of the information transfer apparatus which concerns on embodiment of this invention. It is a figure which shows the corresponding | compatible table which the information transfer apparatus which concerns on embodiment of this invention produces | generates and utilizes.

Explanation of symbols

  12 basic communication network, 22 information transfer device, 24-1 to 24-n radio base station device, 26-1 to 26-m radio terminal station device, 28-0 to 28-n communication port, 28L-0 to 28L- n Communication line.

Claims (3)

A backbone communication port connected to the backbone communication network;
A plurality of communication ports , each assigned an IP address including a common network address and individual host address, and a port number, and connected to a plurality of radio base stations ;
Wherein the MAC address uniquely assigned to the radio terminal station communicating with the radio base station, Netw network address and before each quinic line terminal station assigned in common to the plurality of communication ports a correspondence information generation means for generating association information that associates with including IP address host address assigned individually, before Symbol port number, a,
With identifying the IP address of the wireless terminal station which is the destination of the relevant packet information from the packet information received from the backbone communication network, the communication port of the identified IP address in the corresponding information in the associated port number only and information transfer means transmits the packet information, and transfers the packet information only to the radio base station connected to the communication port,
Equipped with a,
The correspondence information includes a quality assurance parameter associated with the IP address,
The information transfer device transfers the packet information received from the backbone communication network at a transfer rate based on the quality assurance parameter . The information transfer device according to claim 1,
The information transfer apparatus , wherein the quality assurance parameter is determined based on a communication service in the wireless terminal station . The information transfer device according to claim 1 or 2,
The correspondence information generating means, when the wireless terminal station switches the wireless base station that transmits and receives packet information, the MAC address assigned to the wireless terminal station and the wireless terminal station newly transmits and receives information. Updating the correspondence information to associate the port number assigned to the communication port to which the wireless base station is connected,
The information transfer means transfers the wireless terminal station to a wireless base station to which information is newly transmitted / received at a speed that is faster than a transfer speed based on a quality assurance parameter and that does not affect other communication traffic. An information transfer apparatus characterized by that.

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