CN106211141A

CN106211141A - The retransmission method of the stream of a kind of WLAN roaming stations and device

Info

Publication number: CN106211141A
Application number: CN201510218813.2A
Authority: CN
Inventors: 林云云
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2015-04-30
Filing date: 2015-04-30
Publication date: 2016-12-07
Anticipated expiration: 2035-04-30
Also published as: CN106211141B

Abstract

The invention discloses retransmission method and the device of the stream of a kind of WLAN roaming stations, in order to solve that STA flow amount forward efficiency present in prior art is low and waste network bandwidth resources, problem that roamer's Service disruption ratio is high.The method includes: an AP receives the first data message that STA sends, a described AP is the AP of association after described STA roams, IP address in the subnet that source IP address is the 2nd AP place of described first data message, described 2nd AP is the AP of the front association of described STA roaming；Described first data message is after described STA association the oneth AP, the data message in the stream that described STA is newly generated；The described source IP address of described first data message is converted to specify IP address by a described AP, and described appointment IP address is the IP address in the subnet at a described AP place, and forwards described first data message after conversion.

Description

The retransmission method of the stream of a kind of WLAN roaming stations and device

Technical field

The present invention relates to communication technical field, particularly relate to the forwarding of the stream of a kind of WLAN roaming stations Method and device.

Background technology

WLAN (English: wireless local area network, it is called for short: the terminal in WLAN) Website (English: station, abbreviation: STA) roaming refers in a wlan, guarantor as WLAN Under the unbroken premise of card business, STA is between access point (English: access point, to be called for short AP) Mobile.

In a wlan, if the number of AP is the most, may be managed by multiple wireless lan controllers, Therefore may be managed by identical wireless lan controller with associated AP after roaming before STA roaming, As shown in Figure 1, it is also possible to managed by different wireless lan controllers, as shown in Figure 2.In Fig. 2, Local AP (English: home AP, to be called for short HAP) refers to what STA associated after entering WLAN first AP；Managing this HAP is the first wireless lan controller.Other places AP (English: foreign AP, letter Claim FAP) refer to the AP that STA associates after roaming, manage this FAP is that the second WLAN controls.

Roaming is divided into two-layer roaming and three layers of roaming.Two layers of roaming refer to that STA roams in a subnet, i.e. The AP that before roaming, the AP of STA association and STA after roaming associates is in same subnet.Therefore, two layers Under roaming, Internet protocol (Internet Protocol the is called for short IP) address prefix of subnet does not changes. In three layers of roaming, STA is from a sub-network roaming to another subnet, and the IP address prefix of two subnets is not With.Under three layers of roaming scence, need the business ensureing STA not interrupt, i.e. the IP address of STA can not Change.But due to STA by a sub-network roaming to another subnet, the IP of described STA Address is the IP address in the subnet before roaming, therefore, and stream network at place after roaming that STA produces In can not be by the gateway forwards of the subnet after roaming.Typically access first with STA for this The stream of the STA after roaming, as home agent, is forwarded to local generation by tunnel by an equipment in subnet Reason, then the gateway of the subnet that described STA accesses first it is transmitted to by home agent.With HAP for local generation As a example by reason, the FAP that the stream that after roaming, STA produces associates after first passing through roaming, then by FAP and pipe The tunnel managed between second wireless lan controller of this FAP is transmitted to the second wireless lan controller, Again by the second wireless lan controller by the second wireless lan controller and the first wireless local network control Tunnel between device processed is transmitted to the first wireless lan controller, then by the first wireless lan controller It is transmitted to HAP, by HAP by self by the tunnel between the first wireless lan controller and HAP The gateway forwards of the subnet at place is gone out.

Therefore, forwarded by multiple tunnels, cause forward-path to exist more roundabout: occur user Under spanning gateway roaming scence, tunnel is spliced by three sections, the stream that STA produces after roaming need through Cross the first wireless lan controller and the second wireless lan controller gets to home agent.Therefore exist AP and manage the wireless lan controller of this AP distant time, the forward efficiency of the stream of STA is low, And waste network bandwidth resources, the bandwidth of non-roaming service traffics can be taken simultaneously.

Summary of the invention

The embodiment of the present invention provides retransmission method and the device of the stream of a kind of LAN roaming stations, in order to solve STA flow amount forward efficiency low and waste network bandwidth resources problem.

First aspect, embodiments provides the retransmission method of the stream of a kind of WLAN roaming stations, Including:

The first data message that first access point AP receiving station STA sends, a described AP is described The AP of association, the subnet that source IP address is the 2nd AP place of described first data message after STA roaming In IP address, described 2nd AP be described STA roaming before association AP；Described first data message After described STA association the oneth AP, the data message in the stream that described STA is newly generated；

The described source IP address of described first data message is converted to specify IP address by a described AP, And forwarding described first data message after conversion, described appointment IP address is the son at a described AP place IP address in net.

In conjunction with first aspect, in the first possible implementation of first aspect, also include:

Oneth AP receives the second data message that described STA sends, and described second data message is second Data message in the old stream of AP, the old stream of described 2nd AP is to associate described 2nd AP at described STA In the case of, the stream that described STA produces；

Described second data message is passed through between a described AP and described 2nd AP by a described AP Tunnel be sent to described 2nd AP.

In conjunction with the first possible implementation of first aspect, the realization that the second in first aspect is possible In mode, before a described AP receives the second data message that STA sends, described method also includes:

A described AP receives tuple and the IP address of described 2nd AP of the old stream of described 2nd AP；

A described AP sets up first-class forwarding-table item in stream forwarding list, described first-class forwarding-table item Key assignments is the tuple of the old stream of described 2nd AP, and the content of described first-class forwarding-table item includes an AP And the purpose IP address, tunnel in the tunnel between the 2nd AP, purpose IP address, described tunnel is described second The IP address of AP；

Described second data message is passed through between a described AP and described 2nd AP by a described AP Tunnel be sent to the 2nd AP, including:

A described AP searches the stream forwarding list item mated with described second data message in stream forwarding list, It is described first-class forwarding that a described AP finds the stream forwarding list item mated with described second data message List item, obtains the IP address of described 2nd AP in described first-class forwarding-table item；

The tunnel of the IP address that a described AP uses purpose IP address, tunnel to be described 2nd AP sends Described second data message.

In conjunction with any one in the possible implementation of the second of the first of first aspect and first aspect Kind, in the third possible implementation of first aspect, a described AP is by described first datagram The described source IP address of literary composition is converted to described appointment IP address, including:

A described AP searches the stream forwarding list item mated with described first data message in stream forwarding list, When a described AP finds the stream forwarding list item mated with described first data message, obtain described stream Port numbers in forwarding-table item, the described source IP address of described first data message is changed by a described AP For described appointment IP address, and the source port number of described first data message is converted to described first number According to the port numbers in the described stream forwarding list item of message coupling.

In conjunction with any one in the possible implementation of the second of the first of first aspect and first aspect Kind, in the 4th kind of possible implementation of first aspect, a described AP is by described first datagram The described source IP address of literary composition is converted to described appointment IP address, including:

A described AP searches the stream forwarding list item mated with described first data message in stream forwarding list, When described stream forwarding list lacks the stream forwarding list item mated with described first data message, described first AP is the stream assignment of port numbers belonging to described first data message, and a described AP is by described first datagram The described source IP address of literary composition is converted to described appointment IP address, and by the source of described first data message Slogan is converted to the described port numbers of distribution；

A described AP sets up second forwarding-table item in stream forwarding list, described second forwarding-table item Key assignments is the tuple of the stream belonging to described first data message, and the content of described second forwarding-table item includes point The described port numbers joined.

In conjunction with the 4th kind of possible implementation of first aspect, in the 5th kind of possible realization of first aspect In mode, also include:

A described AP sets up the 3rd stream forwarding list item in stream forwarding list, described 3rd stream forwarding list item Key assignments is the tuple of the stream belonging to described first data message after conversion, described first-class forwarding-table item interior Described first data before holding the described source IP address including described first data message before changing and changing The source port number of message；

A described AP receives the 3rd data message being sent to described STA, and described 3rd data message belongs to The stream belonging to described first data message after conversion, the purpose IP address of described 3rd data message is Described appointment IP address, the destination slogan of described 3rd data message is the described port numbers of distribution；

The purpose IP address of described 3rd data message is converted to state the first data message by a described AP Described source IP address, is converted to first before described conversion by the destination slogan of described 3rd data message The source port number of data message；

A described AP forwards described 3rd data message after conversion.

Second aspect, embodiments provides the retransmission unit of the stream of a kind of WLAN roaming stations, Described device is arranged in an AP, and a described AP is the AP of association, institute after described STA roams State device to include:

Receiver module, the first data message sent for receiving station STA, described first data message Source IP address is the IP address in the subnet at the 2nd AP place, and described 2nd AP is described STA roaming The AP of front association；After described first data message is described STA association the oneth AP, described STA newly produces The raw data message in stream；

Processing module, the described source IP address of the first data message for described receiver module is received Be converted to specify IP address；

Sending module, described first data message after forwarding the conversion of described processing module, described appointment IP address is the IP address in the subnet at a described AP place.

In conjunction with second aspect, in the first possible implementation of second aspect, described receiver module, Being additionally operable to receive the second data message that described STA sends, described second data message is the old of the 2nd AP Data message in stream, the old stream of described 2nd AP is the situation associating described 2nd AP at described STA Under, the stream that described STA produces；

Described sending module, described second data message being additionally operable to receive described receiver module passes through institute The tunnel stated between an AP and described 2nd AP is sent to described 2nd AP.

In conjunction with the first possible implementation of second aspect, the realization that the second in second aspect is possible In mode, described receiver module, before being additionally operable to receive the second data message that STA sends, receive described the The tuple of the old stream of two AP and the IP address of described 2nd AP；

Described processing module, is additionally operable to set up first-class forwarding-table item in stream forwarding list, described first circulation The key assignments of forwarding list item is the tuple of the old stream of described 2nd AP, and the content of described first-class forwarding-table item includes The purpose IP address, tunnel in the tunnel between the oneth AP and the 2nd AP, purpose IP address, described tunnel is The IP address of described 2nd AP；And in stream forwarding list, search the circulation mated with described second data message Forwarding list item, finding the stream forwarding list item mated with described second data message is described first-class forwarding-table item, Obtain the IP address of described 2nd AP in described first-class forwarding-table item；

Described second data message is passed through between a described AP and described 2nd AP by described sending module Tunnel be sent to described 2nd AP and be specially described sending module and use purpose IP address, tunnel to be described the The tunnel of the IP address of two AP sends described second data message.

In conjunction with any one in the possible implementation of the second of the first of second aspect and second aspect Kind, in the third possible implementation of second aspect, described processing module is by described first datagram The described source IP address of literary composition is converted to described appointment IP address, particularly as follows:

The stream forwarding list item mated with described first data message is searched, when finding and institute in stream forwarding list When stating the stream forwarding list item of the first data message coupling, obtain the port numbers in described stream forwarding list item, by institute The described source IP address stating the first data message is converted to described appointment IP address, and by described first number The port in the described stream forwarding list item of described first data message coupling is converted to according to the source port number of message Number.

In conjunction with any one in the possible implementation of the second of the first of second aspect and second aspect Kind, in the 4th kind of possible implementation of second aspect, described processing module is by described first datagram The described source IP address of literary composition is converted to described appointment IP address, particularly as follows:

The stream forwarding list item mated with described first data message is searched, when described circulation is sent out in stream forwarding list When lacking, in table, the stream forwarding list item mated with described first data message, a described AP is described first Stream assignment of port numbers belonging to data message, a described AP is by the described source IP of described first data message Address is converted to described appointment IP address, and is converted to by the source port number of described first data message point The described port numbers joined；And in stream forwarding list, set up second forwarding-table item, described second forwarding-table item The tuple that key assignments is the stream belonging to described first data message, the content of described second forwarding-table item includes The described port numbers of distribution.

In conjunction with the 4th kind of possible implementation of second aspect, in the 5th kind of possible realization of second aspect In mode, described processing module, it is additionally operable in stream forwarding list, set up the 3rd stream forwarding list item, the described 3rd The key assignments of stream forwarding list item is the tuple of the stream belonging to described first data message after conversion, described first-class Before the content of forwarding-table item includes described source IP address and the conversion of described first data message before conversion The source port number of described first data message；

Described receiver module, is additionally operable to receive the 3rd data message being sent to described STA, described 3rd number The stream belonging to described first data message after conversion, purpose IP of described 3rd data message is belonged to according to message Address is described appointment IP address, and the destination slogan of described 3rd data message is the described port of distribution Number；

Described processing module, is additionally operable to the purpose of described 3rd data message received by described receiver module IP address is converted to state the described source IP address of the first data message, by the purpose of described 3rd data message Port numbers is converted to the source port number of the first data message before described conversion；

Described sending module, is additionally operable to described 3rd data message after forwarding the conversion of described processing module.

Owing to STA is when initially accessing WLAN, the IP address of STA just has determined as this and initially accesses AP place subnet in IP address, the source IP address of the data message of stream newly generated after roaming Being the IP address of STA, the AP accessed after roaming cannot be by this data message subnet at this AP place Middle forwarding, is required for roaming tunnel and forwards.Utilizing the scheme that the embodiment of the present invention provides, STA is newly generated Stream need not be forwarded by roaming tunnel, but by the source IP address network ground of the data message of this stream Location conversion (English: network address translation, it is called for short: NAT), the source IP address after NAT IP address in the subnet of the AP of association after roaming for STA, can be directly in subnet after this roaming Forward, thus improve forward efficiency.Newly generated stream need not detour through wireless lan controller, So the resource of the network bandwidth has obtained Appropriate application.

Accompanying drawing explanation

Fig. 1 is that a kind of STA roams schematic diagram；

Fig. 2 is that another kind of STA roams schematic diagram；

The retransmission method flow process of the stream of a kind of WLAN roaming stations that Fig. 3 provides for the embodiment of the present invention Figure；

The stream forwarding list schematic diagram that Fig. 4 provides for the embodiment of the present invention；

The another kind of stream forwarding list schematic diagram that Fig. 5 provides for the embodiment of the present invention；

Another stream forwarding list schematic diagram that Fig. 6 provides for the embodiment of the present invention；

Another stream forwarding list schematic diagram that Fig. 7 provides for the embodiment of the present invention；

The retransmission method stream of the stream of the another kind of WLAN roaming stations that Fig. 8 provides for the embodiment of the present invention Cheng Tu；

The retransmission unit signal of the stream of a kind of WLAN roaming stations that Fig. 9 provides for the embodiment of the present invention Figure；

The forwarding unit of the stream of a kind of WLAN roaming stations that Figure 10 provides for the embodiment of the present invention shows It is intended to.

Detailed description of the invention

In order to make the object, technical solutions and advantages of the present invention clearer, below in conjunction with accompanying drawing to this Bright it is described in further detail.

The embodiment of the present invention provides retransmission method and the device of the stream of a kind of WLAN roaming stations, in order to Solve the problem that STA flow amount forward efficiency is low and wastes network bandwidth resources.Wherein, method and apparatus is base In same inventive concept, due to method and device, to solve the principle of problem similar, therefore apparatus and method Enforcement can repeat no more in place of repetition with cross-reference.

The embodiment of the present invention, by being made a distinction by the stream that STA produces, is divided into: before roaming, STA is at Yuan Guan The stream that produced of AP of connection with after roaming at the stream newly generated for AP newly associated.And to STA generation Two kinds of streams carry out different disposal: the stream of the generation of AP in former association front to roaming is still through roaming tunnel Forward such that it is able to ensure that existing business is not interrupted, to stream newly generated on the AP of new association after roaming Carry out NAT, be converted to roam background by the source IP address of each data message of stream newly generated after roaming IP address in net.Owing to STA is when initially associating certain AP, the IP address of STA is determined as IP address in the subnet at this AP place initially associated, the data message in stream newly generated after roaming Source IP address be the IP address of STA, after roaming, the subnet at the AP place of association cannot directly lead to The gateway that after crossing this roaming, associated AP is corresponding forwards.Therefore the AP associated after roaming is by this source IP ground IP address in the subnet at the AP place that location associates after being converted to roaming.

The embodiment of the present invention is data message forwarding is gone out by the mode sent out based on circulation.Send out for circulation It is described as follows:

Each data message composition with identical tuple that website sends flows, and the website that equipment receives is sent out After first data message of the stream sent, the tuple in this data message is looked into general forward table (such as matchmaker Body Access Control (English: media access control, it is called for short: MAC) table, access control list (English Literary composition: access control list, is called for short ACL) etc.) obtain action that this data message is performed.And root Setting up a stream forwarding list item in stream forwarding list according to checking result, this stream forwarding list item includes key assignments and content. Key assignments, for providing the index information of stream forwarding list item in follow-up data message lookup stream forwarding list, typically wraps Include the tuple in data message, such as by the source IP address of data message, purpose IP address, protocol number, Source port number and the five-tuple of destination slogan composition.Content includes the action message performed for data message, Such as include next-hop ip address or MAC Address, outgoing interface index, quality of service (English: quality Of service, is called for short: QoS) etc..

One other data message flowed in addition to first data message is properly termed as the subsequent datagrams of this stream Literary composition.When equipment receives follow-up data message, find key value in stream forwarding list by tuple in data message Joining the stream forwarding list item of this tuple, if finding the list item mating this tuple, this data message is subsequent packet, Without finding the list item of this tuple of key value match, then this data message is first data of a new stream Message.If follow-up data message, then the content that equipment directly includes according to the stream forwarding list item of coupling should Follow-up data message forwards.If the first data message, equipment is according in the stream forwarding list item set up Content is by this first data message forwarding.

Embodiments provide the retransmission method of the stream of a kind of LAN roaming stations, as it is shown on figure 3, The method includes:

Step 301, an AP receives the first data message that STA sends, and a described AP is described The AP of association after the AP, a described AP of association are described STA roaming after STA roaming, described first The source IP address of data message is the IP address in the subnet at the 2nd AP place, and described 2nd AP is institute The AP associated before stating STA roaming, described first data message is institute after described STA association the oneth AP State the data message in the newly generated stream of STA.

Wherein, an AP and the 2nd AP is in different subnets.

Step 302, the described source IP address of described first data message is converted to specify by a described AP IP address, described appointment IP address is the IP address in the subnet at a described AP place, and forwarding turns Described first data message after changing.

Wherein, it is intended that IP address is the IP address being exclusively used in NAT of an AP.Specify IP address Can be static state setting, it is also possible to be that DynamicHost arranges agreement (English: Dynamic Host Configuration Potocol, is called for short: DHCP) server is an AP distribution.DHCP service Device can be realized by the wireless lan controller of management the oneth AP.Can the oneth AP start time, It is that an AP distributes an IP address as specifying IP address by Dynamic Host Configuration Protocol server.Can also have When STA associates an AP, Dynamic Host Configuration Protocol server is that one IP address of AP distribution is as appointment IP address.Can also be when there being STA to roam into an AP, Dynamic Host Configuration Protocol server is an AP distribution One IP address is as specifying IP address.The IP address being exclusively used in NAT of the oneth AP can only have One, i.e. this appointment IP address；Oneth AP can also have multiple IP address being exclusively used in NAT, example As first specifies IP address and second to specify IP address.

Oneth AP searches in stream forwarding list after receiving data message and mates with this data message described Stream forwarding list item.If an AP finds the stream forwarding list item mated with this data message, then according to being somebody's turn to do This data message of the contents processing of stream forwarding list item.The key assignments of the stream forwarding list item mated with data message is number Tuple according to the stream belonging to message.This data message is the follow-up data message in stream, the stream forwarding list of this stream The stream forwarding list item that item mates with this data message exactly.

After STA association the oneth AP, newly generated stream is properly termed as newly flowing.Before STA association the oneth AP Produce and last till STA be associated with an AP after stream be properly termed as old stream.Mate with data message Stream forwarding list item can be the stream forwarding list item of old stream, it is also possible to be the stream forwarding list item of new stream.

If an AP searches less than the stream forwarding list item mated with this data message, an AP is this number Its stream forwarding list item is set up according to the stream belonging to message.Due to the stream forwarding list item not mated with this data message, This data message is first data message of the stream that STA produces when sending this data message, and therefore this stream is New stream.

First data message is the data message in new stream.First data message can be the first number of new stream According to message, it is also possible to be the follow-up data message of this stream.If the first data message is the first number of new stream According to message, an AP to set up stream forwarding list item for this new stream.Needed for this stream forwarding list item includes NAT Parameter, the follow-up data message of this new stream is NAT according to this stream forwarding list item and forwards.Oneth AP The first data message after conversion can be forwarded according to the destination address of the first data message, specifically can turn Issue the gateway of the subnet at an AP place, then gone out by gateway forwards, or be transmitted to an AP Other STA in the subnet at place.Oneth AP can also be regardless of the destination address of the first data message, will First data message forwarding gives the WLAN manager of management the oneth AP, then by WLAN Manager forwards this first data message according to the destination address of the first data message.

Owing to STA is when initially accessing WLAN, the IP address of STA just have determined as STA this IP address in the subnet at the AP place of Shi Guanlian, the source IP of the data message of stream newly generated after roaming Address is the IP address of STA, and after roaming, the AP of STA association is by the source IP address of this data message NAT is the IP address after STA roams in the subnet at the AP place of association, then directly at an AP Forwarding in the subnet at place, thus improve forward efficiency, the resource of the network bandwidth has obtained Appropriate application.

If the stream produced during STA association the 2nd AP not yet terminates after roaming occurs, STA association the Also can produce and send the data message in this stream during one AP.Now, an AP receives described STA The second data message sent, described second data message is the data message in the old stream of the 2nd AP.The The old stream of two AP refers to the STA past roaming into AP stream of generation during association the 2nd AP, and And this stream not yet terminates after roaming association the oneth AP.The tuple of the second data message associates with described STA The tuple of the data message in the old stream of the 2nd AP sent during the 2nd AP is identical.A described AP Described second data message is sent to described by the tunnel between a described AP and described 2nd AP 2nd AP.

If the stream produced during STA association the 2nd AP not yet terminates when roaming occurs, the 2nd AP's Stream forwarding list still remains with the stream forwarding list item of this stream.For avoiding customer service to interrupt, an AP will Data message in the old stream of the 2nd AP is sent to the 2nd AP, then by the 2nd AP according in its stream forwarding list The stream forwarding list item of this stream continues with this data message.In order to identify which message belongs to the old of the 2nd AP Stream, after STA roaming, the tuple of the old stream of the 2nd AP and the address of the 2nd AP are sent to an AP. A described AP receives tuple and the IP address of described 2nd AP of the old stream of the 2nd AP.Described first AP sets up first-class forwarding-table item in stream forwarding list, and the key assignments of described first-class forwarding-table item is described The tuple of the old stream of two AP, the content of described first-class forwarding-table item include an AP and the 2nd AP it Between the purpose IP address, tunnel in tunnel, purpose IP address, described tunnel is the IP address of described 2nd AP.

Wherein, the tunnel between an AP and the 2nd AP pre-builds.

Described second data message is passed through between a described AP and described 2nd AP by a described AP Tunnel be sent to the 2nd AP, specifically can be in the following manner:

A described AP searches the stream forwarding list item mated with described second data message in stream forwarding list, It is described first-class forwarding that a described AP finds the stream forwarding list item mated with described second data message List item, obtains the IP address of described 2nd AP in described first-class forwarding-table item.A described AP makes Described second data message is sent with the tunnel of the IP address that purpose IP address, tunnel is described 2nd AP.

Tuple can include source IP address and purpose IP address, it is also possible to includes stream label.Or including association View number, source port number and destination slogan etc..Such as tuple is five-tuple, include source IP address, mesh IP address, protocol number, source port number and destination slogan.

Wherein, a described AP receives the tuple of the old stream of the 2nd AP, specifically can be in the following manner:

The first implementation:

A described AP receives the stream forwarding list item of the old stream of the 2nd AP.Then this stream forwarding list item is obtained Key assignments in tuple.The stream forwarding list item of the old stream of the 2nd AP is from the 2nd AP.Wherein, the 2nd AP Send all stream forwarding list items of the STA roaming into an AP still retained in its stream forwarding list.Due to The old stream of the 2nd AP is the stream produced during association the 2nd AP in the STA past roaming into an AP, And this stream not yet terminates after STA roams, the stream forwarding list item that the 2nd AP sends includes second The stream forwarding list item of the old stream of AP.2nd AP can be directly to the old stream of AP transmission the 2nd AP Stream forwarding list item, it is also possible to send the old stream of the 2nd AP through wireless lan controller to an AP Stream forwarding list item.

The second implementation:

A described AP directly receives the tuple of the old stream of the 2nd AP.

The tuple of the old stream of the 2nd AP is from the 2nd AP.2nd AP directly can send the to an AP The tuple of the old stream of two AP；2nd AP can also send to an AP through wireless lan controller The tuple of the old stream of the 2nd AP；2nd AP can also send the 2nd AP's to wireless lan controller The stream forwarding list item of old stream, in the stream forwarding list item of the old stream that wireless lan controller extracts the 2nd AP Tuple, sends the tuple of the old stream of the 2nd AP to an AP.2nd AP can extract its stream forwarding list In each tuple of all stream forwarding list items of the STA roaming into an AP of still retaining.2nd AP The tuple of the stream forwarding list item extracted includes the tuple of the old stream of the 2nd AP.

A described AP receives first data message that the first data message is new stream that STA sends, The described source IP address of described first data message is converted to described appointment IP address by a described AP, Can be accomplished by:

The first implementation:

A described AP searches the stream forwarding list item mated with described first data message in stream forwarding list, When described stream forwarding list item lacks the stream forwarding list item mated with described first data message, described first AP obtains the appointment IP address of this STA, and a described AP is by the described source IP of described first data message Address is converted to the appointment IP address obtained.If an AP not yet distributed appointment IP ground for this STA Location, the i.e. first data message is the first number of first the new stream produced after this STA is associated with an AP According to message, an AP is that this STA distributes an appointment IP address, and records appointment IP of this STA Location.This appointment IP address is that being exclusively used in the IP address of NAT of an AP is not yet assigned to other STA Appointment IP address.If an AP is assigned with appointment IP address, the i.e. first data for this STA Message is the first of other the new streams produced after first the new stream produced after this STA is associated with an AP Individual data message, an AP extracts the appointment IP address of this STA of record.

Described AP stream belonging to this first data message in stream forwarding list is set up second and is forwarded List item, the key assignments of described second forwarding-table item is the tuple of the stream belonging to described first data message.Second The content of stream forwarding list item includes the source IP address of the first data message and the appointment IP address of this STA, as Stream forwarding list shown in Fig. 4.In Fig. 4, the five-tuple of the new stream that STA produces: source IP address is 1.1.1.10, purpose IP address be A1, source port number be 80, destination slogan be B1, protocol number be C1, Specifying IP address is 2.2.2.2.The five-tuple of another new stream that this STA produces: source IP address be 1.1.1.10, Purpose IP address is A2, source port number is 80, destination slogan is B2, protocol number is C2, it is intended that IP Address is 2.2.2.2, only uses one to specify IP ground the various flows of one STA with an AP in Fig. 4 As a example by location.Oneth AP can also be that multiple streams of a STA use different appointment IP addresses.Fig. 4 In the appointment IP address of other 2 STA different.

Wherein, when described stream forwarding list item lacks the stream forwarding list item mated with described first data message, A described AP obtains the appointment IP address of this STA, and according to the purpose IP address of the first data message Obtain by looking into address resolution protocol (English: Address Resolution Protocol, to be called for short ARP) table Corresponding MAC Address.The described source IP address of described first data message is converted to by a described AP Described appointment IP address, and the target MAC (Media Access Control) address of described first data message is converted to the first datagram The MAC Address that civilian purpose IP address is corresponding.The content of the second forwarding-table item then set up also includes Target MAC (Media Access Control) address after the target MAC (Media Access Control) address of one data message and conversion.Purpose after NAT MAC Address is the MAC Address that the purpose IP address of described first data message is corresponding.

The second implementation:

A described AP searches the stream forwarding list item mated with described first data message in stream forwarding list, When described stream forwarding list item lacks the stream forwarding list item mated with described first data message, described first AP obtains the appointment IP address of this STA, and a described AP is the flow point belonging to described first data message Joining port numbers, the described source IP address of described first data message is converted to described appointment by a described AP IP address, and the source port number of described first data message is converted to the described port numbers of distribution.

Concrete, it is also possible to the IP address specified is saved in the content of second forwarding-table item, such as Shown in Fig. 5 shown in stream forwarding list.In Fig. 5, the five-tuple of the new stream that STA produces: source IP address For 1.1.1.10, purpose IP address be A1, source port number be 80, destination slogan be B1, protocol number be C1, it is intended that IP address is 2.2.2.2, an AP be this stream distribution port numbers be 3761.This STA produces The five-tuple of another raw new stream: source IP address is 1.1.1.10, purpose IP address is A2, source port Number be 80, destination slogan be B2, protocol number be C2, it is intended that IP address is 2.2.2.2, an AP Difference in the port numbers distributed for this stream and a upper stream forwarding list item, is 3762.With first in Fig. 5 As a example by AP only uses an IP address specified, the port numbers that all streams are allocated is the most different.First AP can also have multiple IP address being exclusively used in NAT, and the IP address and second that such as first specifies is specified IP address, if then the IP addresses specified of two streams are different, the port numbers for the distribution of the two stream can With identical.

Alternatively, if an AP only uses an IP address specified, also may be used in the IP address that this is specified With IP address by default without recording in the content of each stream forwarding list item.

Wherein, when described stream forwarding list item lacks the stream forwarding list item mated with described first data message, A described AP obtains the appointment IP address of this STA, and according to the purpose IP address of the first data message The MAC Address of correspondence is obtained by looking into ARP table.A described AP is by the institute of described first data message State source IP address and be converted to described appointment IP address, and by the purpose MAC ground of described first data message Location is converted to the MAC Address that the purpose IP address of the first data message is corresponding.The second then set up forwards The content of list item also include the first data message target MAC (Media Access Control) address and conversion after purpose MAC ground Location.As shown in Figure 6.Target MAC (Media Access Control) address after changing is the purpose IP address of described first data message Corresponding MAC Address.

A described AP receives the follow-up data message that the first data message is new stream that STA sends, institute State an AP and the described source IP address of described first data message is converted to described appointment IP address, can To be accomplished by:

The first implementation:

A described AP searches the stream forwarding list item mated with described first data message in stream forwarding list, When a described AP finds the second forwarding-table item mated with described first data message, obtain the Appointment IP address in the second forwarding-table item of one data message coupling.A described AP is by described first The described source IP address of data message is converted to described appointment IP address；Wherein, described and described first number The unit that key assignments is the stream belonging to described first data message according to the described second forwarding-table item of message coupling Group.

Concrete, a described AP searches the circulation mated with described first data message in stream forwarding list Forwarding list item, when a described AP finds the second forwarding-table item mated with described first data message, Obtain the appointment IP address in the second forwarding-table item of the first data message coupling.A described AP is by institute The described source IP address stating the first data message is converted to described appointment IP address；If described second forwards When the content of list item also includes specifying target MAC (Media Access Control) address, then perform the mesh of described first data message MAC Address be converted to specify target MAC (Media Access Control) address, this appointment target MAC (Media Access Control) address is described first The target MAC (Media Access Control) address that the purpose IP address of data message is corresponding.Wherein, described with described first datagram The tuple that key assignments is the stream belonging to described first data message of the described second forwarding-table item of literary composition coupling.

The second implementation:

A described AP searches the stream forwarding list item mated with described first data message in stream forwarding list, It is second forward table when a described AP finds the stream forwarding list item mated with described first data message Xiang Shi, obtains the port numbers in the described second forwarding-table item mated with described first data message, described The described source IP address of described first data message is converted to described appointment IP address by the oneth AP, and The described circulation that the source port number of described first data message is converted to described first data message coupling is sent out Port numbers in list item.If the content of described second forwarding-table item also including specify target MAC (Media Access Control) address Time, as shown in Figure 6, then perform the target MAC (Media Access Control) address of described first data message is converted to described finger Determining target MAC (Media Access Control) address, this appointment target MAC (Media Access Control) address is the purpose IP address of described first data message Corresponding target MAC (Media Access Control) address.Wherein, described second circulation that described and described first data message mates The key assignments of forwarding list item is the tuple of the stream belonging to described first data message.

In order to forward the data message mailing to STA, a described AP goes back when setting up second forwarding-table item Setting up the 3rd stream forwarding list item in stream forwarding list, the key assignments of described 3rd stream forwarding list item is the institute after conversion Stating the tuple of stream belonging to the first data message, the content of described first-class forwarding-table item includes before conversion the The source port number of the first data message before the described source IP address of one data message and described conversion.

A described AP receives the 3rd data message being sent to described STA that network side sends, and described the Three data messages belong to the stream belonging to described first data message after conversion, the mesh of described 3rd data message IP address be described appointment IP address, the destination slogan of described 3rd data message be distribution described Port numbers.

A described AP forwards described 3rd data message after conversion.

Wherein, the stream belonging to described 3rd data message is referred to as the stream belonging to described first data message Reciprocal stream.Such as, the business of the stream correspondence belonging to the 3rd data message is that STA1 sends datagram STA2 given in literary composition, and the business of the stream correspondence belonging to the most described first data message is that STA2 sends datagram To STA1.

Such as, the second forwarding-table item of the stream belonging to described first data message is as it is shown in figure 5, then described 3rd stream forwarding list item of the stream belonging to the 3rd data message is the most as shown in Figure 7.

STA initially associates the 2nd AP, subsequently roam to the 3rd AP, finally roam into an AP, first AP is the AP that STA currently associates.Oneth AP, the 2nd AP and the 3rd AP are belonging respectively to three differences Subnet.IP address in the subnet that IP address is the 2nd AP place of STA.

Oneth AP receives tuple and the IP address of the 3rd AP of the old stream of the 3rd AP, and the 3rd AP's is old In the case of stream is for associating the 3rd AP at STA, the stream that STA produces.

Oneth AP sets up the 4th stream forwarding list item in stream forwarding list, and the key assignments of the 4th stream forwarding list item is The tuple of the old stream of three AP, the content of the 4th stream forwarding list item includes between an AP and the 3rd AP The purpose IP address, tunnel in tunnel, this purpose IP address, tunnel is the IP address of the 3rd AP.

Oneth AP receives tuple and the IP address of the 2nd AP of the old stream of the 2nd AP, and the 2nd AP's is old In the case of stream is for associating the 2nd AP at STA, the stream that STA produces.

Oneth AP sets up first-class forwarding-table item in stream forwarding list, and the key assignments of first-class forwarding-table item is The tuple of the old stream of two AP, the content of first-class forwarding-table item includes between an AP and the 2nd AP The purpose IP address, tunnel in tunnel, this purpose IP address, tunnel is the IP address of the 2nd AP.

Oneth AP receives the 4th data message that described STA sends, and the 4th data message is the 3rd AP's Data message in old stream.

Oneth AP searches the stream forwarding list item mated with the 4th data message in stream forwarding list, an AP Finding the stream forwarding list item mated with described 4th data message is the 4th stream forwarding list item, obtains the 4th stream The IP address of the 3rd AP in forwarding-table item.

The tunnel of the IP address that the oneth AP uses purpose IP address, tunnel to be the 3rd AP sends the 4th data Message.

Oneth AP receives the second data message that described STA sends, and the second data message is the 2nd AP's Data message in old stream.

Oneth AP searches the stream forwarding list item mated with the second data message in stream forwarding list, an AP Finding the stream forwarding list item mated with the second data message is first-class forwarding-table item, obtains first-class forwarding The IP address of the 2nd AP in list item.

The tunnel of the IP address that the oneth AP uses purpose IP address, tunnel to be the 2nd AP sends the second data Message.

Oneth AP receives the first data message that STA sends, and the source IP address of the first data message is STA IP address.After first data message is STA association the oneth AP, the data in the stream that STA is newly generated Message.First data message is first data message in the stream that this STA is newly generated.

Oneth AP searches the stream forwarding list item mated with the first data message, stream forwarding list in stream forwarding list The stream forwarding list item that middle shortage is mated with the first data message.Oneth AP is the stream belonging to the first data message Assignment of port numbers.The source IP address of the first data message is converted to specify IP address by the oneth AP.And The source port number of the first data message is converted to the port numbers of distribution.Oneth AP forwards first after changing Data message.

Oneth AP sets up second forwarding-table item in stream forwarding list, and the key assignments of second forwarding-table item is The tuple of the stream belonging to one data message, the content of second forwarding-table item includes the port numbers of distribution.

Oneth AP receives the 5th data message that STA sends, and the source IP address of the 5th data message is STA IP address.5th data message is the follow-up data message of the stream belonging to the first data message, the i.e. the 5th The tuple of data message is identical with the tuple of the first data message.

Oneth AP searches the stream forwarding list item mated with the 5th data message in stream forwarding list.Oneth AP The circulation that stream forwarding list item is the stream belonging to the first data message mated with the 5th data message found Forwarding list item, i.e. second forwarding-table item.Oneth AP obtains the port numbers in described second forwarding-table item. The source IP address of the 5th data message is converted to above-mentioned appointment IP address by the oneth AP, and by the 5th The source port number of data message is converted to the port numbers in the stream forwarding list item of described 5th data message coupling, I.e. the oneth AP is the port numbers of the stream distribution belonging to the first data message.

It addition, an AP determines in each data message and stream forwarding list received in preset duration At least one stream forwarding list item does not mates, then delete at least one stream forwarding list item.Due to a certain stream forwarding list If item does not has any data message matched in scheduled duration, then illustrate that this stream forwarding list item is corresponding Stream has terminated, because in order to save system resource, by this certain stream forwarding list entry deletion.

Below in conjunction with concrete application scenarios, the embodiment of the present invention is illustrated.

Assume that STA (the IP address of STA is 1.1.1.10) roams into AP2 from AP1, then overflow by AP2 Swimming over to AP3, AP3, AP2 are belonging respectively to three different subnets from AP1.

After roaming after associated AP 3, STA sends datagram and is belonging respectively to three below stream:

(1) in the case of associated AP 1, the stream Session1 of generation.

(2) in the case of associated AP 2, the stream Session2 of generation.

(3) in the case of associated AP 3, the stream Session3 of generation.

Wherein, management AP1's is the first wireless lan controller, and management AP2's is the second wireless office Territory net controller, management AP3's is the 3rd wireless lan controller.First overflowing from AP1 at STA Swim over to AP2 and roam into AP3 again, the first wireless lan controller, the second wireless lan controller and 3rd wireless lan controller all can perceive.

For data traffic Session1 having built up on AP1, as shown in Figure 8:

Step 801: the 3rd wireless lan controller determines that STA is roamer.

Step 802: complete STA produce stream tuple roaming forward-backward correlation AP on synchronization.

Specifically, the synchronization on the AP of roaming forward-backward correlation of the tuple of the stream that STA produces refers to: the 3rd Wireless lan controller notifies that the second wireless lan controller obtains the unit of the Session1 that STA1 produces Group, the second wireless lan controller after the tuple getting Session1 from AP2, the second wireless office The tuple of Session1 is sent to the 3rd wireless lan controller by territory net controller again, more wireless by the 3rd Lan controller is issued to AP3.In like manner complete between the tuple of the Session2 AP before and after roaming Synchronize.

Wherein, owing to STA is when being roamed into AP2 by AP1, the second wireless lan controller has led to Know that the first wireless lan controller obtains the Session1 tuple that STA1 produces, the first wireless local network control The tuple of the Session1 got, after the tuple getting Session1 from AP1, is sent to by device processed Second wireless lan controller, then the second wireless lan controller will be got Session1 tuple again and send out Give AP2.Therefore, when STA is roamed into the second wireless lan controller by AP2 again, the 3rd is wireless Lan controller directly can obtain the tuple of Session1 from the second wireless lan controller.

Step 803:AP3 obtains the IP address of AP2 and AP1.

Wherein, step 403 and step 402 upon execution can priorities regardless of time.

Step 804, AP3 sets up first-class forwarding-table item and second forwarding-table item in stream forwarding list. The key assignments of first-class forwarding-table item is the tuple of Session1, the content bag of described first-class forwarding-table item Including the purpose IP address, tunnel in tunnel between AP1 and AP3, purpose IP address, described tunnel is AP1 IP address.Wherein the key assignments of second forwarding-table item is the tuple of Session2, and described second forwards The content of list item includes the purpose IP address, tunnel in the tunnel between AP2 and AP3, described tunnel purpose IP Address is the IP address of AP2.

Step 805, AP3 receives the data message that STA sends；

Step 806, AP3 searches the stream forwarding list item mated with described data message in stream forwarding list.

When the stream forwarding list item mated with described data message found in stream forwarding list, perform step 807；When stream forwarding list lacks the stream forwarding list item mated with described data message, perform step 808.

Step 807, AP3 according to the content in described stream forwarding list item by described data message forwarding.

Concrete, if the stream forwarding list item of data message coupling is first-class forwarding-table item, obtain described first The IP address of the AP1 in stream forwarding list item, and the IP ground using purpose IP address, tunnel to be described AP1 The tunnel of location sends described data message.Wherein, this tunnel is the tunnel between AP1 and AP3.If number Stream forwarding list item according to message coupling is second forwarding-table item, and AP3 obtains in described second forwarding-table item The IP address of AP2, and the tunnel of the IP address using purpose IP address, tunnel to be described AP2 sends Described data message.Wherein, this tunnel is the tunnel between AP2 and AP3.

Step 808, AP3 is the Session3 assignment of port numbers belonging to described data message, and AP3 is by institute The described source IP address stating data message is converted to specify IP address, and by the source of described data message Slogan is converted to the port numbers of distribution.Perform step 809.Here data message is the first of Session3 Individual data message.

Address in the subnet wherein specifying IP address to be AP3 place.

Step 809, AP3 sets up the 3rd stream forwarding list item in stream forwarding list.Described 3rd stream forwarding list item The tuple that key assignments is the Session3 belonging to described data message, the content bag of described 3rd stream forwarding list item Include the port numbers of distribution.

Wherein the 3rd stream forwarding list item of data message coupling, then explanation data message be Session3 except the Follow-up data message outside one data message, AP3 obtains described the mated with described first data message Port numbers in three stream forwarding list items, the described source IP address of described data message is converted to by described AP3 Described appointment IP address, and the source port number of described data message is converted to described data message coupling Described 3rd stream forwarding list item in port numbers.

Embodiments provide the retransmission unit of the stream of a kind of WLAN roaming stations, described setting In an AP, a described AP is the AP of association after described STA roams, as it is shown in figure 9, institute State device and include receiver module 901, processing module 902 and sending module 903.

Receiver module 901, the first data message sent for receiving station STA, described first datagram IP address in the subnet that source IP address is the 2nd AP place of literary composition, described 2nd AP is described STA The AP of association before roaming；After described first data message is described STA association the oneth AP, described STA The newly generated data message in stream；

Processing module 902, the described source of the first data message for described receiver module 901 is received IP address is converted to specify IP address, and described appointment IP address is in the subnet at a described AP place IP address；

Sending module 903, described first data message after forwarding the conversion of described processing module.

Alternatively, described receiver module 901, it is additionally operable to receive the second data message that described STA sends, Described second data message is the data message in the old stream of the 2nd AP, the old stream of described 2nd AP be In the case of described STA associates described 2nd AP, the stream that described STA produces；

Described sending module 903, is additionally operable to described second datagram received by described receiver module 901 Literary composition is sent to described 2nd AP by the tunnel between a described AP and described 2nd AP.

Further, described receiver module 901, before being additionally operable to receive the second data message that STA sends, Receive tuple and the IP address of described 2nd AP of the old stream of described 2nd AP；

Described processing module 902, is additionally operable to set up first-class forwarding-table item in stream forwarding list, described first The key assignments of stream forwarding list item is the tuple of the old stream of described 2nd AP, the content of described first-class forwarding-table item Including the purpose IP address, tunnel in the tunnel between an AP and the 2nd AP, described tunnel purpose IP ground Location is the IP address of described 2nd AP；The stream mated with described second data message is searched in stream forwarding list Forwarding-table item, finding the stream forwarding list item mated with described second data message is described first-class forward table , obtain the IP address of described 2nd AP in described first-class forwarding-table item；

Described second data message is passed through a described AP and described 2nd AP by described sending module 903 Between tunnel be sent to described 2nd AP particularly as follows: described sending module 903 uses tunnel purpose IP ground Location is that the tunnel of the IP address of described 2nd AP sends described second data message.

Wherein in a scene of an embodiment, described processing module 902 is by described first data message Described source IP address be converted to described appointment IP address, particularly as follows:

Wherein in another scene of an embodiment, described processing module 902 is by described first datagram The described source IP address of literary composition is converted to described appointment IP address, particularly as follows:

Further, described processing module 902, it is additionally operable in stream forwarding list, set up the 3rd stream forwarding list item, The key assignments of described 3rd stream forwarding list item is the tuple of the stream belonging to described first data message after conversion, institute State the content of first-class forwarding-table item include described first data message before conversion described source IP address and The source port number of described first data message before conversion；

Described receiver module 901, is additionally operable to receive the 3rd data message being sent to described STA, and described Three data messages belong to the stream belonging to described first data message after conversion, the mesh of described 3rd data message IP address be described appointment IP address, the destination slogan of described 3rd data message be distribution described Port numbers；

Described processing module 902, is additionally operable to described 3rd datagram received by described receiver module 901 The purpose IP address of literary composition is converted to state the described source IP address of the first data message, by described 3rd datagram The destination slogan of literary composition is converted to the source port number of the first data message before described conversion；

Described sending module 903, is additionally operable to described 3rd data after forwarding the conversion of described processing module 902 Message.

Owing to STA is when initially accessing WLAN, the IP address of STA just has determined as STA now IP address in the subnet at the AP place of association, the source IP ground of the data message of stream newly generated after roaming Location is the IP address of STA, and after roaming, the AP of STA association is by the source IP address NAT of this data message IP address in the subnet at the AP place of association after roaming for STA, then directly at an AP place Forwarding in subnet, thus improve forward efficiency, the resource of the network bandwidth has obtained Appropriate application.

The retransmission method of the stream of WLAN roaming stations based on above-described embodiment offer and device, this Bright embodiment additionally provides the forwarding unit of the stream of a kind of WLAN roaming stations, as shown in Figure 10, This equipment includes wireless transceiver 1001, processor 1002, memorizer 1003 and wireline transceiver 1005. Wireless transceiver 1001, processor 1002, memorizer 1003 and wireline transceiver 1005 are connected with each other. The embodiment of the present invention does not limit and between above-mentioned parts, specifically connects medium.The embodiment of the present invention is at Figure 10 In connected with memorizer 1003, between processor 1002 and transceiver by bus 1004, bus is at figure Represent with thick line in 10, the connected mode between other parts, be only by schematically illustrating, do not regard it as It is limited.Described bus can be divided into address bus, data/address bus, control bus etc..For ease of representing, figure Only represent with a thick line in 10, it is not intended that an only bus or a type of bus.

Memorizer 1003 in the embodiment of the present invention, for storing the program code that processor 1002 performs, can Be volatile memory (English: volatile memory), such as random access memory (English: Random-access memory, abbreviation: RAM)；Memorizer 1003 can also be nonvolatile memory (English: non-volatile memory), such as read only memory (English: read-only memory, Abbreviation: ROM), flash memory (English: flash memory), hard disk (it is English: hard disk drive, Abbreviation: HDD) or solid state hard disc (English: solid-state drive, SSD) or memorizer abbreviation: 1003 can be used for carrying or storing have instruction or the desired program code of data structure form energy Enough by any other medium of computer access, but it is not limited to this.Memorizer 1003 can be above-mentioned storage The combination of device.

Processor 1002 in the embodiment of the present invention, can be that a CPU is (English: central Processing unit, is called for short CPU).

Wireless transceiver 1001 can include but are not limited to antenna, for transmitting/receiving wireless LAN message. Wireline transceiver 1005 can include but are not limited to ethernet port, is used for receiving and dispatching wired message.

In the embodiment of the present invention using the forwarding unit of the stream of WLAN roaming stations as an AP or The forwarding unit of the stream of WLAN roaming stations is arranged in an AP, certain for other AP Can also be made up of the forwarding unit of the stream of WLAN roaming stations, the embodiment of the present invention is only with one As a example by AP, (AP) illustrates, an AP is the AP of association after STA roams.

Wireless transceiver 1001 receives the first data message that STA sends, the source of described first data message IP address is the IP address in the subnet at the 2nd AP place, before described 2nd AP is described STA roaming The AP of association；After described first data message is described STA association the oneth AP, described STA is newly generated Stream in data message.

The described source IP address of described first data message is converted to specify IP address by processor 1002；And Described first data message after forwarding processor 1002 conversion, described appointment IP address is described first IP address in the subnet at AP place.

Wireless transceiver 1001 also receives the second data message that described STA sends, described second datagram Literary composition is the data message in the old stream of the 2nd AP, and the old stream of described 2nd AP is for associating institute at described STA In the case of stating the 2nd AP, the stream that described STA produces；

Then described second data message is passed through a described AP and described second by wireline transceiver 1005 Tunnel between AP is sent to described 2nd AP.

Before wireless transceiver 1001 receives the second data message that STA sends, wireline transceiver 1005 Receive tuple and the IP address of described 2nd AP of the old stream of described 2nd AP；

Processor 1002 sets up first-class forwarding-table item in the stream forwarding list that memorizer 1003 stores, described The key assignments of first-class forwarding-table item is the tuple of the old stream of described 2nd AP, described first-class forwarding-table item Content includes the purpose IP address, tunnel in the tunnel between an AP and the 2nd AP, described tunnel purpose IP Address is the IP address of described 2nd AP.

Processor 1002 is searched and described second data message in the stream forwarding list that memorizer 1003 stores The stream forwarding list item joined, processor 1002 finds the stream forwarding list item mated with described second data message For described first-class forwarding-table item, obtain the IP address of described 2nd AP in described first-class forwarding-table item；

Processor 1002 indicates wireline transceiver 1005 to use purpose IP address, tunnel to be described 2nd AP The tunnel of IP address sends described second data message.

Processor 1002 is searched and described first data message in the stream forwarding list that memorizer 1003 stores The stream forwarding list item joined, when finding the stream forwarding list item mated with described first data message, obtains institute Stating the port numbers in stream forwarding list item, a described AP is by the described source IP address of described first data message Be converted to described appointment IP address, and the source port number of described first data message is converted to described Port numbers in the described stream forwarding list item of one data message coupling.

Processor 1002 is searched and described first data message in the stream forwarding list that memorizer 1003 stores The stream forwarding list item joined, when lacking the stream forwarding list mated with described first data message in described stream forwarding list Xiang Shi, the processor 1002 stream assignment of port numbers belonging to described first data message, by described first number Described appointment IP address is converted to according to the described source IP address of message, and by described first data message Source port number is converted to the described port numbers of distribution；

Second forwarding-table item set up in stream forwarding list by processor 1002, described second forwarding-table item Key assignments is the tuple of the stream belonging to described first data message, and the content of described second forwarding-table item includes point The described port numbers joined.

Processor 1002 also sets up the 3rd stream forwarding list item, described 3rd stream forwarding list item in stream forwarding list Key assignments be the tuple of the stream belonging to described first data message after conversion, described first-class forwarding-table item Content include conversion before described first data message described source IP address and conversion before described first number Source port number according to message；

Wireless transceiver 1001 receives the 3rd data message being sent to described STA, described 3rd datagram Literary composition belongs to the stream belonging to described first data message after conversion, the purpose IP ground of described 3rd data message Location is described appointment IP address, and the destination slogan of described 3rd data message is the described port numbers of distribution；

Purpose IP of described 3rd data message that wireless transceiver 1001 is then received by processor 1002 Address is converted to state the described source IP address of the first data message, by the destination of described 3rd data message Slogan is converted to the source port number of the first data message before described conversion；And forward the described 3rd after conversion Data message.

One of ordinary skill in the art will appreciate that all or part of step realizing in above-described embodiment method The program of can be by is carried out instruction processing unit and is completed, and described program can be stored in computer-readable storage medium In matter, described storage medium is that non-transience is (English: non-transitory) medium, such as random access memory Memorizer, read only memory, flash memory, hard disk, solid state hard disc, tape (it is English: magnetic tape), (English: floppy disk), CD is (English: optical disc) and combination in any for floppy disk.

The present invention is the respective flow chart of the method and apparatus with reference to the embodiment of the present invention and block diagram describes 's.It should be understood that can by each flow process in computer program instructions flowchart and block diagram and square frame, with And the flow process in flow chart and block diagram and the combination of square frame.These computer program instructions can be provided to general The processor of computer, special-purpose computer, Embedded Processor or other programmable data processing device is to produce A raw machine so that the instruction performed by the processor of computer or other programmable data processing device Produce for realizing in one flow process of flow chart or multiple flow process and one square frame of block diagram or multiple square frame The device of the function specified.

The above, the only present invention preferably detailed description of the invention, but protection scope of the present invention not office Being limited to this, any those familiar with the art, can be easily in the technical scope that the invention discloses The change expected or replacement, all should contain within protection scope of the present invention.Therefore, the protection of the present invention Scope should be as the criterion with scope of the claims.

Claims

1. the retransmission method of the stream of a WLAN roaming stations, it is characterised in that including:

The first data message that first access point AP receiving station STA sends, a described AP is described The AP of association after STA roaming, the source internet protocol IP address of described first data message is the 2nd AP IP address in the subnet at place, described 2nd AP is the AP of the front association of described STA roaming；Described After one data message is described STA association the oneth AP, the data message in the stream that described STA is newly generated；

2. the method for claim 1, it is characterised in that also include:

3. method as claimed in claim 2, it is characterised in that a described AP receives STA and sends The second data message before, described method also includes:

4. the method as described in claims 1 to 3 is arbitrary, it is characterised in that a described AP is by described The described source IP address of the first data message is converted to described appointment IP address, including:

5. the method as described in claims 1 to 3 is arbitrary, it is characterised in that a described AP is by described The described source IP address of the first data message is converted to described appointment IP address, including:

6. method as claimed in claim 5, it is characterised in that also include:

A described AP forwards described 3rd data message after conversion.

7. the retransmission unit of the stream of a WLAN roaming stations, it is characterised in that described device sets Being placed in the first access point AP, a described AP is the AP of association, described dress after described STA roams Put and include:

Receiver module, for receiving the first data message that described STA sends, described first data message Source internet protocol IP address is the IP address in the subnet at the 2nd AP place, and described 2nd AP is institute The AP associated before stating STA roaming；Described first data message is after described STA associates a described AP, Data message in the stream that described STA is newly generated；

Processing module, the described source IP address of the first data message for described receiver module is received Being converted to specify IP address, described appointment IP address is the IP address in the subnet at a described AP place；

Sending module, described first data message after forwarding the conversion of described processing module.

8. device as claimed in claim 7, it is characterised in that described receiver module, is additionally operable to receive The second data message that described STA sends, described second data message is the data in the old stream of the 2nd AP Message, the old stream of described 2nd AP is in the case of described STA associates described 2nd AP, described STA The stream produced；

9. device as claimed in claim 8, it is characterised in that described receiver module, is additionally operable to receive Before the second data message that STA sends, receive the tuple of the old stream of described 2nd AP and described 2nd AP IP address；

Described processing module, is additionally operable to set up first-class forwarding-table item in stream forwarding list, described first circulation The key assignments of forwarding list item is the tuple of the old stream of described 2nd AP, and the content of described first-class forwarding-table item includes The purpose IP address, tunnel in the tunnel between the oneth AP and the 2nd AP, purpose IP address, described tunnel is The IP address of described 2nd AP；In stream forwarding list, search the circulation mated with described second data message send out List item, finding the stream forwarding list item mated with described second data message is described first-class forwarding-table item, Obtain the IP address of described 2nd AP in described first-class forwarding-table item；

10. the device as described in claim 7 to 9 is arbitrary, it is characterised in that described processing module is by institute The described source IP address stating the first data message is converted to described appointment IP address, particularly as follows:

11. devices as described in claim 7 to 9 is arbitrary, it is characterised in that described processing module is by institute The described source IP address stating the first data message is converted to described appointment IP address, particularly as follows:

12. devices as claimed in claim 11, it is characterised in that described processing module, are additionally operable to Stream forwarding list is set up the 3rd stream forwarding list item, the key assignments of described 3rd stream forwarding list item be conversion after described The tuple of the stream belonging to the first data message, the content of described first-class forwarding-table item include conversion before described The source port number of described first data message before the described source IP address of the first data message and conversion；