JP2003188911A - Flooding amount controller for radio packet network - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress the constriction on to a communication zone caused by flooding in a radio packet network. <P>SOLUTION: A radio station which repeats flooding frames acquires a flooding flow rate Q and processes a flooding frame based on a preset passing rate in accordance with the flooding flow rate Q. When the flooding flow rate Q is lower than a threshold Q1, all flooding frames are transferred and, when the flow rate Q is equal to or higher than the threshold Q1 and lower than another threshold Q2 (Q1<Q2), one half of the flooding frames is transferred and the other half of the frames is canceled. When the flooding flow rate Q1 is equal to or higher than the threshold Q2, all flooding frames are not transferred, but cancelled. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flooding amount control device for controlling the amount of packets transmitted by flooding in a wireless packet network including a plurality of wireless stations.

[0002]

2. Description of the Related Art Flooding is a technique for transmitting a frame (packet) containing predetermined information in a broadcast format (broadcast) from a predetermined transmission source in a wireless packet network. If a wireless station in the network has a relay function,
As shown in FIG. 5, each wireless station relays (transfers) the flooding frame, so that the flooding frame is transmitted to the entire wireless packet network. This flooding has been conventionally used, for example, when acquiring the path (communication route) of each wireless station in a wireless packet network.

In the network illustrated in FIG. 5, a wireless station receives the same flooding frame from multiple wireless stations. For example, the wireless station C receives the flooding frame from the wireless station A and transfers it to the wireless stations F and G, but the wireless station C also receives the same flooding frame from the wireless station B again. there's a possibility that. Therefore, in such a wireless packet network, each wireless station is provided with a function of discarding a previously transmitted flooding frame so that the flooding frame is not transmitted again through the same route. That is, waste of the bandwidth due to flooding is suppressed by transferring only the minimum necessary flooding frame.

[0004]

However, in the above-mentioned conventional network, when a plurality of flooding frames occur at approximately the same time, the ratio of the flooding frame transmission band in the entire information transmission band increases, It may be difficult to transmit other information. This problem is likely to occur when the density of wireless stations is high or under a condition where links between wireless stations are easily disconnected, and particularly in a packet network of mobile wireless stations in which wireless stations are freely movable.

[0005]

An apparatus for controlling a flooding amount in a wireless packet network according to the present invention includes a flooding flow rate measuring unit for measuring a flooding flow rate and a flooding flow rate for transmitting a packet by the flooding. And a flooding amount adjusting unit for limiting the flooding amount accordingly. With such a configuration, it is possible to suppress pressure on the information transmission band due to the flooding frame, and avoid network congestion.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing the configuration of a wireless station 10 of a wireless packet network according to an embodiment of the present invention.

The wireless station 10 according to the embodiment shown in FIG. 1 functions as a wireless transmitting station that transmits predetermined information, as a wireless receiving station that receives information from the wireless transmitting station, and as a wireless transmitting station. It has a function as a wireless relay station that relays information transmitted to and from a wireless receiving station that is not within the communication area of the wireless transmitting station. Which of these stations will function is determined by the control information received by the arithmetic processing unit 12 of the wireless station 10 (for example, information indicating the address of the wireless relay station or the wireless receiving station included in the header of the received frame). It

The radio station 10 controls each part of the radio station 10 and also performs a process of selecting the above-mentioned station functions, a process of limiting transmission of a flooding frame according to a flooding flow rate, a process of generating / acquiring a baseband signal, and the like. Performs processing (for example, modulation / demodulation, amplification, filtering, A / D conversion, D / A conversion, etc.) for communication between the arithmetic processing unit (for example, CPU) 12 and other wireless stations or access points. Communicates with a wireless communication unit 14 for performing, a storage unit (for example, RAM, ROM, hard disk, etc.) 16 for storing various information related to arithmetic processing, and a cycle timer 18 for measuring a transmission cycle / reception cycle of information. And an antenna 20 for

In this embodiment, when the wireless station 10 functions as a wireless relay station, the flooding frame transmission is restricted. The transmission restriction of the flooding frame will be described below with reference to the drawings. FIG. 2 shows a wireless station 1.
3 is a flowchart of the processing of the received frame in FIG.
FIG. 4 is an explanatory diagram showing a configuration example of a flooding frame, and FIG. 4 is an explanatory diagram showing an example of processing of a flooding frame according to a flooding flow rate.

The arithmetic processing unit 12 determines whether or not the received frame (hereinafter referred to as a received frame) is a flooding frame (step S10), and if the frame is not a flooding frame, the frame is processed. Normal processing is performed (step S12). Step S
In 10, whether or not it is a flooding frame,
It can be determined from the information included in the frame (for example, information indicating the source and the destination described in the header of the frame). In the example of FIG. 3, the header of the frame includes the destination station ID, the source station ID, and the broadcast ID.
It is included. The flooding frame is the destination station I
Information indicating flooding as D and broadcast ID (identification information of flooding frame)
Therefore, the arithmetic processing unit 12 can determine whether or not the received frame is a flooding frame by acquiring and confirming these.

The arithmetic processing unit 12 refers to the identification information of the previously processed (transferred) flooding frame stored in the storage unit 16, and the received flooding frame has already been processed (transferred). It is determined whether or not (step S14). Then, when the flooding frame has already been processed, the arithmetic processing unit 12 discards the received frame (step S16), and shifts to the processing of the next received frame. On the other hand, when the received flooding frame is unprocessed, the identification information of the flooding frame is registered in the storage unit 16 (step S1).
8). As the identification information of the flooding frame registered in the storage unit 16, for example, the above-mentioned destination station ID or broadcast ID can be used.

Next, the arithmetic processing unit 12 acquires the flooding flow rate, that is, the passing amount (the number of times of reception or the number of times of transmission) of the flooding frame per unit time in the wireless station 10, and the flooding frame is calculated according to the flooding flow rate. It is determined whether or not to restrict the transmission of (step S20). More specifically, as illustrated in FIG. 4, for example, the arithmetic processing unit 12 sets the flooding flow rate at the wireless station 10 to Q, and sets the flooding flow rate thresholds set for the processing here to Q1 and Q2 (Q1). As <Q2), the flooding frame is processed under the following conditions (a) to (c). The horizontal axis of FIG. 4 represents the flooding flow rate Q in the wireless station 10, and the vertical axis represents the passage rate of the flooding frame. Here, the pass rate is the number of flooding frames transferred by the wireless station 10 with respect to the number of unprocessed (untransferred) flooding frames received by the wireless station 10.

(A) When 0 <Q <Q1, the flooding frame is processed so as to have the highest passing rate (lowest discard rate). In the example of FIG. 4, all flooding frames are transferred without being discarded (step S22).

(B) When Q1≤Q <Q2, the flooding frame is processed so that the passing rate is lower than (a) (the discarding rate is higher than (a)). In the example of FIG. 4, half of the flooding frames are discarded (step S16) and half are transferred (step S22). More specifically,
The passing / discarding of the flooding frame is repeated alternately.

(C) When Q ≧ Q2, the flooding frame is processed so as to have the lowest passing rate (highest discard rate). In the example of FIG. 4, all flooding frames are discarded (step S16).

Note that the processing determination of the flooding frame by the arithmetic processing unit 12 in step S20 indicates information (for example, (a) to (c) described above) indicating the processing corresponding to the flooding flow rate stored in the storage unit 16. Information) and the flooding flow rate at that time. Information indicating the processing according to the flooding flow rate is stored in the storage unit 16 as a numerical data group or a function, for example. In the present embodiment, the arithmetic processing unit 12 corresponds to the flooding amount adjustment unit.

The identification information of the flooding frame to be discarded in step S20 is stored in the storage unit 16
Is erased (step S24).

The flooding flow rate acquired in step S20 is acquired by the arithmetic processing unit 12 before or after any step after step S10 of the received frame processing. For example, it is between steps S10 and S14, between steps S14 to S20, between steps S20 and S22, or after step S22. The flooding flow rate is calculated, for example, as the number of flooding frames per unit time (the number of passages, the number of receptions, the number of transmissions, etc.). In the present embodiment, the arithmetic processing unit 12 corresponds to the flooding flow rate measuring unit.

The radio station 10 according to the present embodiment is an information processing device (for example, personal computer or the like; not shown).
And a wireless communication device connected (or built-in) to it (for example, a wireless LAN card detachable from an information processing device, a wireless L
It can be configured as an AN device or the like; not shown).
In this case, the arithmetic processing unit 12, the storage unit 16, and the cycle timer 18 can be configured as a part of the information processing device (CPU, memory, etc.), and the wireless communication unit 14 can be configured as a part of the wireless communication device. . Further, in this case, the arithmetic processing unit 12 can be caused to perform each of the above processes according to the program held in the program holding unit such as the memory or the hard disk of the information processing device. This program
For example, it is stored in a computer-readable storage medium (for example, CD-ROM, DVD, MO, etc.), read by a removable device connected (or built-in) to the information processing apparatus, and installed in the program holding unit.

It is also possible to configure the radio station 10 as a radio communication device in which all of the above-mentioned components (the arithmetic processing unit 12, the radio communication unit 14, the storage unit 16 and the cycle timer 18) are integrated.

Although the preferred embodiment of the present invention has been described above, the present invention is not limited to the above embodiment. For example, in the above-described embodiment, the passage rate of the flooding packet is set in three stages according to the flooding flow rate, but a higher number of stages may be set, or the passage rate may be gradually reduced as the flooding flow rate increases. You may set a different passing rate.

[0022]

As described above, according to the present invention,
By limiting the forwarding of flooding frames according to the flooding flow rate, the pressure on the transmission band due to flooding frames is suppressed, and network congestion can be avoided.
The data transmission efficiency can be improved.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a wireless station that performs flooding amount control according to an embodiment of the present invention.

FIG. 2 is a flowchart of received frame processing in a wireless station that performs flooding amount control according to the embodiment of the present invention.

FIG. 3 is an explanatory diagram showing a configuration example of a flooding frame.

FIG. 4 is a diagram showing a setting example of a flooding frame transmission restriction according to a flooding flow rate in the flooding amount control according to the embodiment of the present invention.

FIG. 5 is an explanatory diagram showing transfer of flooding frames in a wireless packet network.

[Explanation of symbols]

10 wireless stations (wireless communication devices), 12 arithmetic processing units, 1
4 wireless communication unit, 16 storage unit, 18 cycle timer, 20
antenna.

   ─────────────────────────────────────────────────── ─── Continued front page    F term (reference) 5K030 GA03 GA13 HA08 HC09 JL01                       KA01 LC01 LC11 LD05 MA04                       MB09 MC08

Claims (2)

[Claims] 1. A device for controlling a flooding amount in a wireless packet network, comprising a flooding flow rate measuring unit for measuring a flooding flow rate, and a flooding for limiting packet transmission by flooding according to the flooding flow rate. A flooding amount control device comprising: an amount adjusting unit; 2. A flag in a wireless packet network, comprising: a computer; a flooding flow rate measuring means for measuring a flooding flow rate; and a flooding amount adjusting means for limiting transmission of packets by flooding according to the flooding flow rate. A program for functioning as a ding amount control device.