CN100450079C

CN100450079C - A wireless mesh network data processing method and wireless mesh network

Info

Publication number: CN100450079C
Application number: CNB2005100538091A
Authority: CN
Inventors: 高江海; 潘强; 梁斌; 黎静; 雒战平
Original assignee: Huawei Technologies Co Ltd
Current assignee: Honor Device Co Ltd
Priority date: 2005-03-11
Filing date: 2005-03-11
Publication date: 2009-01-07
Anticipated expiration: 2025-03-11
Also published as: CN1832452A

Abstract

The invention relates to a wireless mesh network data processing method and a wireless mesh network. The wireless mesh network system includes multiple wireless mesh network access points (MAPs) for data forwarding through wireless channels, and is characterized in that multiple wireless channels are used to forward data between the MAPs. In the wireless mesh network data processing method, multiple wireless mesh network access points (MAPs) of the wireless mesh network perform data forwarding through wireless channels, and there are multiple wireless channels for carrying data forwarding. The present invention uses a plurality of different wireless channels between MAPs to bear data, avoids the interference phenomenon generated when transmitting data between the same wireless channels, and utilizes wireless channel resources to the greatest extent.

Description

A kind of based on wireless mesh network data processing method and based on wireless mesh network

Technical field

The present invention relates to wireless communication field, relate in particular to a kind of based on wireless mesh network data processing method and based on wireless mesh network.

Technical background

In recent years, WLAN (wireless local area network) WLAN (Wireless Local Area Network) technology has obtained developing rapidly in the access field, according to huge message transmission rate that it had, WLAN also is considered to a main rival of mobile data communication part behind 3G or the 3G.But WLAN also has its weak point, wherein topmost one is that the coverage of access point AP (Access Point) is comparatively limited, if will provide wireless coverage in a relatively large zone, just need in this area, dispose a plurality of access points, thereby increase the cost of building based on the public broadband net of WLAN.Though people have proposed some solutions to this, improve adaptability of wireless covering and position or the like as coexistence by multiple wireless technology, be to be cost mostly in these methods to increase access point or to reduce network operation efficient.So people have turned to another kind of network configuration to sight---based on wireless mesh network WMN (Wireless Mesh Network), hope overcomes existing inherent defect in the conventional wireless network by this brand-new network configuration, realizes the once change in the WiMAX field.

WMN is a kind of novel broadband wireless network structure, the distributed network of promptly a kind of high power capacity, two-forty, and it is different from traditional wireless network.On network topology, WMN is similar to mobile Ad hoc network, but the basic static state of the most of nodes of network is mobile, and as power, change in topology is less without battery; On single-hop inserted, WMN can regard a kind of special WLAN as.Because higher reliability, bigger retractility and lower cost of investment are arranged, WMN has been written in IEEE802.16 (being commonly called as WiMax) wireless MAN WMAN (the WirelessMunicipal Area Network) standard as a kind of can the solution " last kilometer " bottleneck problem new network structure.As one of ideal style of following WMAN core net, very likely challenge 3G technology, make up the brand-new network technology of following B3G/4G network, various in the world organizations have launched the research to WMN one after another, propose the Networking Solutions ﹠ provisioned of oneself, and released the product of oneself to market in time.For example: the WMN of Nortel company has carried out the city and has covered in the Taibei.Yet these WMN products are not have unified international standard to follow, and what each tissue adopted is own privately owned standard.Formulate about the standard of WMN research in the world at present, be responsible for by IEEE802.11S working group.

As everyone knows, concealed nodes and exposed node are the main bottlenecks that influences the WMN performance, how in WMN, according to each node current wireless channel behaviour in service, reasonably radio channel resource is adjusted in planning, reduce to greatest extent and disturb,, have great significance to be adapted to the variation of different application.

As shown in Figure 1, WMN is made of MAP (Mesh Access Point) network element node, and the major function of MAP has: (1) is responsible for the access of various wireless site STA (station); (2) will jump MAP to next from the data that other MAP come transmits.WMN can be considered as having the fusion of wireless access network and two kinds of network functions of wireless core network (wireless forwarding net).

Among the WMN of Fig. 1, STA1 sends data to STA2, and STA1 inserts from MAP2, MAP2 be responsible for from WMN1, finding a paths (STA1-〉MAP2-〉MAP3-STA2 or

STA1-〉MAP2-〉MAP1-〉MAP5-〉MAP4-〉MAP3-〉STA2 or other) data forwarding is jumped to next, until MAP3, be transmitted to STA2 by MAP3.

As shown in Figure 1, along with the increase of WMN scale, particularly when offered load acquired a certain degree, the interference between adjacent node can make the performance meeting rapid deterioration of WMN, at present, does not also have good solution.

Summary of the invention

Purpose of the present invention has proposed the minimizing signal exactly and has disturbed, and improves the based on wireless mesh network data transmission quality, a kind of method and system of protection and raising network performance, and for this reason, the present invention adopts following technical scheme:

A kind of based on wireless mesh network, comprise a plurality of based on wireless mesh network access point MAP that carry out data forwarding by wireless channel, between the described MAP, adopt a plurality of wireless channels to transmit data, when described MAP adds based on wireless mesh network, with all neighbours MAP of this MAP distribute but the common factor of idle channel constitutes accurate idle channel set, wherein, the MAP of described adding based on wireless mesh network is not first MAP that adds based on wireless mesh network;

When described accurate idle channel set is not sky, from the corresponding neighbours MAP set of described accurate idle channel set, select a neighbours MAP, select an accurate idle channel from described accurate idle channel set, the MAP of described adding based on wireless mesh network connects by this accurate idle channel and this neighbours MAP.

Described network between the interactional MAP, adopts different wireless channels to transmit data.

Described network between each MAP, all adopts different wireless channels to transmit data.

Described network also comprises based on wireless mesh network gateway unit MGW, and described MGW connects external network by upstream Interface, and carries out data passes by wireless channel and MAP.

Described MGW is connected in network craft terminal, described MGW sends network topological information and each MAP wireless channel behaviour in service information of based on wireless mesh network to described network craft terminal, by described network craft terminal based on wireless mesh network is carried out network operation.

Described MGW is a plurality of.

A kind of based on wireless mesh network data processing method, a plurality of based on wireless mesh network access point MAP by based on wireless mesh network carry out data forwarding by a plurality of wireless channels, the wireless channel of described carrying data forwarding is a plurality of, when described MAP adds based on wireless mesh network, with all neighbours MAP of this MAP distribute but the common factor of idle channel constitutes accurate idle channel set, wherein, the MAP of described adding based on wireless mesh network is not first MAP that adds based on wireless mesh network;

Described method between the MAP of phase mutual interference, adopts different wireless channels to transmit data.

Described method between the different MAP, all adopts different wireless channels to transmit data.

Described based on wireless mesh network also is provided with based on wireless mesh network gateway unit MGW, described MGW connects the external network service equipment by upstream Interface, and send the network topological information of based on wireless mesh network to described network craft terminal, based on wireless mesh network is safeguarded and the radio channel resource adjustment that described MGW carries out data forwarding by wireless channel and MAP by described network craft terminal.

Described MGW is a plurality of.

External network webmaster NMS carries out comprising when radio channel resource is adjusted to MAP:

S1, NMS ask to target MAP by the MGW adjustment of posting a letter, and require target MAP to adjust to the work wireless channel that MGW requires from certain wireless channel of having worked;

After S2, target MAP receive message, carry out and adjust wireless channel, and results messages is returned to MGW.

Described method, when described MAP adds based on wireless mesh network, adopt following steps:

A, judge that whether this MAP is the 1st MAP among the based on wireless mesh network WMN, if then under default wireless channel, work; If not, enter step B;

B, the wireless channel that obtains all neighbours MAP of this MAP use information, and the common factor that takies wireless channel of all neighbours MAP constitutes and takies the wireless channel set, and all have distributed but the common factor of idle channel constitutes accurate idle channel set;

C, judge that whether the set of accurate idle channel is empty, if not, enters step D, if enter step e;

D, from the corresponding neighbours MAP set of accurate idle channel set, select a neighbours MAP, concentrate an accurate idle channel of selection and this neighbours MAP to connect from accurate idle channel, this wireless channel is put into the busy channel set, and make this neighbours MAP know this information; Then this process end is finished in channel adjustment, otherwise returns step C;

E, from neighbours MAP set, select a MAP as judging MAP, choose an accurate idle channel the MAP if can judge from this, adopt this accurate idle channel and this judgement MAP to connect, the radio frequency operation of adjusting oneself is put into this channel the busy channel set simultaneously on this channel; Simultaneously, this judgement MAP learns on this channel and connects; Then this process end is finished in channel adjustment, otherwise returns step C; If can not choose accurate idle channel from judging MAP, choosing is judged one of MAP busy channel and this judgement MAP has been connected at random; Then this process end is finished in channel adjustment, otherwise returns step C.

New wireless mesh network system and data processing method that the present invention proposes, between MAP, adopt the corresponding a plurality of channels of a plurality of radio frequencies to carry data, avoid the interference phenomenon that when transmitting data, produces between the identical wireless channel, utilized radio channel resource to greatest extent.

Description of drawings

Fig. 1 is the structural representation of based on wireless mesh network in the prior art;

Fig. 2 is the structural representation of the based on wireless mesh network that proposes of the present invention;

Fig. 3 is in the embodiment of the invention, the schematic diagram of phase mutual interference between the MAP;

Fig. 4 is in the technical solution of the present invention, increases the schematic network structure of MGW;

Fig. 5 is the schematic flow sheet that MAP adds network in the embodiment of the invention;

Fig. 6 is a channel adjustment interacting message schematic diagram in the embodiment of the invention.

Embodiment

Below in conjunction with Figure of description the specific embodiment of the present invention is described.

As shown in Figure 1, along with the increase of WMN scale, particularly when offered load acquired a certain degree, the interference between adjacent MAP can make the performance meeting rapid deterioration of WMN.How adjusting the radio channel resource of each MAP, reduce to greatest extent and disturb, with protection and raising network performance, be adapted to the variation of different application, is the problem that the present invention mainly considers.

As shown in Figure 2, it is the new based on wireless mesh network structural representation that the present invention proposes, this based on wireless mesh network comprises a plurality of MAP swap datas that carry out data forwarding by wireless channel, as seen from the figure, the present invention is on the based on wireless mesh network basis of prior art, increase the quantity of wireless channel, that is to say the quantity of transmitting radio frequency, guarantee between the interactional MAP, use different wireless channels to transmit data, perhaps for simplicity as far as possible, make and all adopt different wireless channels to come swap data between the different MAP, like this, can be reduced in the data transmission procedure phase mutual interference of same wireless channel greatly.Such as: 4 MAP are arranged, A, B, C, D, A and B need data interaction, and C and D need data interaction, if A, B, C, D influence each other (rf power signal collision), the wireless channel that A, B data interaction are adopted should be different with the wireless channel that C, D data interaction are adopted; If A, B and C, D do not influence each other (rf power signal interacts very weak), then the wireless channel of the wireless channel of A, B data interaction employing and C, D data interaction employing can be identical.

The basic access mechanism of IEEE802.11MAC (Medium Access Control) layer is distributed coordination function DCF (Distributed Coordination Function), and MAP MAC layer also can adopt this working mechanism to finish forwarding of data between MAP.Because the characteristic that wireless medium WM (Wireless Medium) is had, making can only have a MAP to send or receive data at a plurality of MAP within the scope of influencing each other on this wireless channel in a certain moment on the same wireless channel, other MAP must silence just can avoid data collision, and this has just limited the performance of WMN greatly.Therefore, can have more wireless channel to receive or the transmission data in order to make a plurality of MAP within the scope of influencing each other, each MAP is provided with a plurality of forwarding radio frequencies, is operated in respectively on the different wireless channels, and might as well establish the wireless channel number is N (N is more than or equal to 2).Wherein, realize transmitting, inserting radio frequency separation physically.

The characteristic of WMN is at present: the basic static state of MAP does not move, and transfer of data does not have center control coordinator node between MAP.As shown in Figure 3, suppose that MAP1, MAP2 have Frame alternately, at this moment if MAP3 needs and the MAP4 interaction data, on same wireless channel, if MAP3 sends data, will influence MAP1, MAP2 normal communication.Along with the increase of network size, the increasing the weight of of offered load, this conflict can cause the rapid deterioration of network performance, therefore needs a center control nodes, adjusts certain or even all MAP radio channel resources dynamically, to protect and the raising network performance.

Simultaneously, but as the WMN of an operation management, each WMN also must have a centre management node (or centre management node inlet), to realize monitoring and the management to this WMN.Therefore, the present invention introduces (based on wireless mesh network gateway) MGW, MGW has also increased the collection of topology to this WMN, each MAP channel behaviour in service and mutual with the management of webmaster NMS (Networkmanagement system) except the function of common MAP.As shown in Figure 3 and Figure 4, the present invention has increased network element unit---MGW on existing based on wireless mesh network basis, and MGW connects external network by upstream Interface, and carries out data passes by wireless channel and MAP.MGW sends the network topological information of based on wireless mesh network to described network craft terminal, by described network craft terminal based on wireless mesh network is carried out network operation.Regular or the irregular execution of MGW WMN collecting topology and each MAP wireless channel behaviour in service.

Further we can MGW be set to a plurality ofly, as shown in Figure 4, have so just formed a lot of subnets, and this example is 2, is respectively WMN1 and WMN2.The major function of MAP has: (1) is responsible for the access of various wireless site STA (station); (2) will jump MAP to next from the data that other MAP come transmits.Therefore, WMN of the present invention can be considered as having the fusion of wireless access network and two kinds of network functions of wireless core network (wireless forwarding net).

Among Fig. 4, the based on wireless mesh network gateway of subnet WMN1 is MGW1.NMS implements the WMN1 subnet is managed by MGW1.MGW1 regular or irregular collection of wireless channel behaviour in service and storage with network topology and each MAP are made a strategic decision for NMS.NMS can monitor, dynamically adjust the radio channel resource of MAP, to guarantee the performance of the maximum performance of network.Here MAP has a plurality of forwarding radio frequencies, is operated in different wireless channels respectively, therefore can dynamically adjust.

Therefore, MGW is the centre management node (or centre management node inlet) of WMN subnet, and each MAP wireless channel of storage networking topological sum uses information.

Corresponding with this networking thought, data processing method of the present invention, then a plurality of MAP by WMN carry out data forwarding by wireless channel, and the wireless channel that wherein carries data forwarding is between different MAP, and is all inequality as far as possible.

The MAP that data are transmitted in these a plurality of wireless channel carryings carries out respective description below.

On the basis of existing technology, a plurality of wireless channels that increase between the MAP connect, and when MAP adds the initial of this based on wireless mesh network, adopt following method:

Prerequisite: after powering on, under the default setting, a plurality of radio frequencies of each MAP are operated in different default wireless channels respectively; The work wireless channel of each MAP is divided into: take wireless channel, accurate idle wireless channel.Wherein take wireless communication Dow Jones index MAP and be operated on this wireless channel, and adopt this wireless channel to connect with other MAP; Accurate idle wireless communication Dow Jones index MAP is operated on this channel, and is current on this wireless channel, not and other MAP connect.

As shown in Figure 5, be a schematic flow sheet of a new MAP adding based on wireless mesh network of present embodiment, as seen from the figure, this adition process is as follows:

S1, judge that whether this MAP is first MAP in this WMN subnet, if, enter step S2, if not, enter step S3;

Under default wireless channel, work after the 1st MAP in S2, the WMN subnet powers on, do not carry out wireless channel and select to adjust;

After S3, non-the 1st MAP power on, carry out the process that adds the WMN subnet, the beginning wireless channel is selected to adjust;

The adjustment principle is as follows: after the individual MAP of n (n is more than or equal to 2) powers on, find neighbours MAP on every side by neighbor discovery process, obtain the work wireless channel of those neighbours MAP simultaneously.The common factor formation of the wireless channel that all take takies the wireless channel set; The common factor of all accurate idle wireless channels constitutes accurate idle wireless channel set.Suppose neighbor node MAP2 and the MAP3 of MAP1 such as us, wherein MAP2 take wireless channel for 1}, accurate idle no drawing lines be 3,4}, the wireless channel that takies of MAP3 is { 2}, accurate idle wireless channel is that { 4}, then the set of the accurate idle wireless channel of the neighbours MAP of MAP1 is { 4}.

S4, judge that whether accurate idle wireless channel set is empty, if not, enters step S5, if enter step S6;

S5, from all neighbours MAP, select a neighbours MAP by certain rule (such as: priority, link-quality etc.), again by ad hoc rules (such as: the accurate idle channel of this neighbours MAP) concentrate to select an idle wireless channel of standard and this neighbours MAP to connect from the idle wireless channel of standard, this wireless channel is put into the busy channel set, and make this neighbours MAP know this information; Then this process end is finished in channel adjustment, otherwise returns step S4;

S6, from all neighbours MAP, select a neighbours MAP as judging neighbours MAP by certain rule (such as: the number of the binding of having set up, link-quality etc.);

Do you S7, judge in the distribution wireless channel of this judgement neighbours MAP that accurate idle wireless channel is arranged? if have, enter step S8, if do not enter step S9;

S8, if can from this judges the distribution wireless channel of neighbours MAP, choose an idle wireless channel of standard, adopt this accurate idle wireless channel and this judgement neighbours MAP to connect, the radio frequency operation of adjusting oneself is put into this wireless channel the wireless channel that takies that takies wireless channel set, judgement neighbours MAP simultaneously and is gathered on this wireless channel; Simultaneously, this judgement neighbours MAP learns on this wireless channel and connects; Then this process end is finished in channel adjustment, otherwise returns step S4;

S9, if can not choose accurate idle wireless channel from judging neighbours MAP, according to certain rule (such as: the number of having set up binding), choosing judges that one of neighbours MAP has taken wireless channel and this judgement neighbours MAP connects at random; Then this process end is finished in channel adjustment, otherwise returns step S4.

The termination condition of above-mentioned adjustment process is: all wireless channel adjustment of this new MAP are finished.

So far, each MAP preserves the wireless channel behaviour in service of oneself.So just, finish the MANET between the MAP, reduced the interference between MAP simultaneously to greatest extent.

Among the present invention, each MAP has neighbours MAP information and the wireless channel behaviour in service information of oneself, for the MGW collection of WMN subnet.Webmaster is by the use information of the wireless channel of the regular or irregular collection network topology information of MGW and each MAP, and the radio channel resource of whole network is adjusted in planning.

The adjustment of wireless channel when this method not only is adapted to MAP and powers on, also be applicable to simultaneously power on after, NMS is to the planning of whole WMN wireless channel.Each MAP can regular or irregular execution above-mentioned steps, realizes the management to WMN.

In the solution of the present invention, webmaster can carry out the adjustment of radio channel resource dynamically according to the information of collecting to each MAP by MGW.

As shown in Figure 6, NMS monitors, adjusts the radio channel resource of whole network by the regular or irregular collection network topological sum of MGW wireless channel behaviour in service information among the present invention, and process is as follows:

(1) NMS gives the MAP of target by the MGW adjustment request (Channel modify request) of posting a letter, and requires target MAP to adjust to the work wireless channel that MGW requires from certain wireless channel of having worked;

(2) after target MAP receives message, carry out and adjust, success or failure (Channel modifyresponse) message are returned to MGW (or webmaster);

So far, NMS finishes the radio channel resource management of WMN network MAP.

The present invention is directed to can run, manageable WMN network, the system and method that adopts different radio channel switch data between a kind of different MAP is provided, can improve the based on wireless mesh network performance greatly, reduce the phase mutual interference of based on wireless mesh network in data exchange process.

MAP of the present invention finishes MANET automatically, and increase, offered load that this ad hoc network method can alleviate along with network size add under the weight condition, and the phenomenon of WMN network performance rapid deterioration also is a kind of effective workaround to concealed terminal and exposed terminal;

At can run, manageable WMN network, the present invention has introduced managed network element MGW, and a kind of dynamic adjustment MAP radio channel resource is provided, and optimizes a kind of solution of network performance, this method can realize the centralized management to the WMN network, reduces maintenance workload.

The above is the preferred embodiments of the present invention only, is not limited to the present invention, and for a person skilled in the art, the present invention can have various changes and variation.Within the spirit and principles in the present invention all, any modification of being done, be equal to replacement, improvement etc., all should be included within the claim scope of the present invention.

Claims

1. A wireless mesh network, comprising a plurality of wireless mesh network access points MAP for data forwarding through wireless channels, characterized in that between the MAPs, multiple wireless channels are used to forward data,

When the MAP joins the wireless mesh network, the intersection of allocated but idle channels of all neighboring MAPs of the MAP forms a quasi-idle channel set, wherein the MAP joining the wireless mesh network is not the first to join the wireless mesh network. MAP of the mesh network;

When the quasi-idle channel set is not empty, select a neighbor MAP from the neighbor MAP set corresponding to the quasi-idle channel set, select a quasi-idle channel from the quasi-idle channel set, and join the wireless mesh The MAP of the network establishes a connection with the neighbor MAP through the quasi-idle channel.

2. The network according to claim 1, characterized in that MAPs that influence each other use different wireless channels to forward data.

3. The network according to claim 2, characterized in that each MAP uses different wireless channels to forward data.

4. The network according to claim 1, 2 or 3, further comprising a wireless mesh network gateway unit MGW, said MGW is connected to an external network through an uplink interface, and performs data transmission with the MAP through a wireless channel.

5. The network according to claim 4, wherein the MGW is connected to network maintenance equipment, and the MGW transmits the network topology information of the wireless mesh network and the use status information of each MAP wireless channel to the A network maintenance device, which performs network maintenance on the wireless mesh network.

6. The network according to claim 5, characterized in that there are multiple MGWs.

7. A wireless mesh network data processing method, in which a plurality of wireless mesh network access points MAP of the wireless mesh network perform data forwarding through wireless channels, and it is characterized in that the wireless channels for carrying data forwarding are multiple When the MAP joins the wireless mesh network, the intersection of all the allocated but idle channels of the MAP’s neighbors MAP constitutes a quasi-idle channel set, wherein the MAP joining the wireless mesh network is not the first Join the MAP of the wireless mesh network;

8. The method according to claim 7, characterized in that different wireless channels are used to forward data between mutually interfering MAPs.

9. The method according to claim 8, characterized in that different wireless channels are used to forward data between different MAPs.

10. The method according to claim 7, 8 or 9, characterized in that the wireless mesh network is further provided with a wireless mesh network gateway unit MGW, and the MGW is connected to an external network maintenance device through an uplink interface, and The network topology information of the wireless mesh network is transmitted to the network maintenance device, and the network maintenance device maintains the wireless mesh network and adjusts wireless channel resources, and the MGW performs data forwarding with the MAP through the wireless channel .

11. The method according to claim 10, characterized in that there are multiple MGWs.

12. The method according to claim 11, characterized in that when the external network management NMS adjusts the wireless channel resources of the MAP, it includes:

S1. The NMS sends a channel adjustment request to the target MAP through the MGW, requesting the target MAP to adjust from a working wireless channel to a working wireless channel required by the MGW;

S2. After receiving the message, the target MAP performs wireless channel adjustment, and returns the result message to the MGW.

13. The method according to claim 9, wherein when the MAP joins the wireless mesh network, the following steps are adopted:

A, judge whether this MAP is the first MAP in the wireless mesh network WMN, if yes, then work under the default wireless channel; if not, enter step B;

B. Obtain the wireless channel usage information of all neighbor MAPs of the MAP, the intersection of occupied wireless channels of all neighbor MAPs constitutes an occupied wireless channel set, and the intersection of all allocated but idle channels constitutes a quasi-idle channel set;

C, judge whether the set of quasi-idle channels is empty, if not, enter step D, if yes, enter step E;

D. Select a neighbor MAP from the neighbor MAP set corresponding to the quasi-idle channel set, select a quasi-idle channel from the quasi-idle channel set to establish a connection with the neighbor MAP, put the wireless channel into the occupied channel set, and make the neighbor MAP Get the information; the process ends when the channel adjustment is completed, otherwise return to step C;

E. Select a MAP from the set of neighbor MAPs as the judgment MAP. If you can pick out a quasi-idle channel from the judgment MAP, use this quasi-idle channel to establish a connection with the judgment MAP, and adjust your radio frequency to work on this channel. At the same time, put this channel into the set of occupied channels; at the same time, the judging MAP learns that a connection has been established on this channel; the process ends when the channel adjustment is completed, otherwise return to step C; if the quasi-idle channel cannot be picked out from the judging MAP, random Select an occupied channel of the judging MAP to establish a connection with the judging MAP; the process ends when the channel adjustment is completed; otherwise, return to step C.