A kind of broadband wireless MAN construction method that class-of-service is provided
Technical field
The invention belongs to broadband wireless MAN (IEEE802.16 WirelessMAN) technical field, is the method that a kind of structure provides the broadband WirelessMAN of class-of-service.
Background technology
IEEE802.16 WirelessMAN is a kind of broadband network [1] Carl Eklund that can provide high-speed radio to insert in the metropolitan area scope, Roger B.Marks, " IEEE Standard802.16:ATechnical Overview of the WirelessMAN
TMAir Interface for BroadbandWireless Access ", IEEE C802.16-02/05,2002.IEEE802.16 working group has issued IEEE Std802.16-2004 on October 1st, 2004, this standard definition work in the fixed broadband wireless access system air interface physical layer (PHY) and media access control layer (MAC) standard of 2-66GHz frequency band.IEEE Std802.16e will be in March, 2005 issue, this standard definition the air interface specification of mobile wide-band wire-less accessing system.IEEE802.16 working group has only formulated the air interface specification of BWA, and does not formulate the standard of utilizing the IEEE802.16 wireless access technology to make up broadband wireless MAN.
Summary of the invention
The object of the present invention is to provide a kind of IEEE802.16 of utilization wireless access technology to make up the method for the broadband wireless MAN that class-of-service is provided.
The broadband wireless MAN system can be divided into three subsystems: base station system, exchange subsystem, management subsystem.
Base station system realizes the wireless channel interconnection between IEEE802.16 terminal and the base station, radio interconnected between base station and the base station.The repertoire that the exchange subsystem has the managing signaling rules is used for call establishment, maintenance and removing are controlled and managed.The major function that the exchange subsystem comprises has: the specific function relevant with user's mobility; Management to Radio Resource; Management to signaling protocol; The portable terminal registration; Authenticating user identification; Route Selection; Label switched path is set up.The management subsystem is carried out Long-distance Control and maintenance to whole wireless MAN, and its major function has: the network operation management comprises user management, network device management, charging, statistics etc.; Safety management; Operation and performance management; System change control; System maintenance and fault recovery.
The broadband wireless city field network system structure as shown in Figure 1, whole communication network is made of wireless network, cable network and other network; Broadband wireless MAN comprises wireless network and two parts of cable network, and other network comprises existing voice communication networks such as PSTN, ISDN, GSM and 3G; Broadband wireless MAN is by transfer gateway and other network interconnection of switching center.The functional entity that constitutes the broadband metropolitan area network network has: air station, switching center, base station, access center, device flag device, registration center, AUC, administrative center, charging center.First three entity belongs to the wireless network part, and back six entities belong to the cable network part, and the interconnection of wireless network and cable network is finished at the access center.Functional entity in the wireless network connects by Radio Link; Cable network adopts traditional IP, passes through optical fiber interconnections between the functional entity wherein.Each entity is finished specific function.
Air station: air station is made of subscriber equipment, supports IEEE802.16-2004 and IEEE802.16e agreement.The user uses these equipment to fix or inserts the IEEE802.16 metropolitan area network movably, obtains needed communication service.Each air station all comprises a wireless terminal, and according to the needs of communication service, air station also can comprise various terminal equipments and terminal adapter.Air station has some identification numbers, in order to identify this air station within the specific limits uniquely.
Base station system: base station system is made up of the equipment that can set up the radio covering in certain zone and communicate by letter with air station.Base station system is made of base station controller and base station transceiver equipment two class functional entitys.Base station controller is controlled and is managed base station transceiver equipment; Base station transceiver equipment is the transceiving letter equipment that covers certain zone.Base station system is supported IPv6 route and MPLS (Multi-Protocol Label Switching) exchange.Base station system is distributed IP address, local or is delivered the IP address for the air station that inserts.
Switching center: switching center exchanges and controls the air station that is positioned at its service area, and the interface with other base station is provided simultaneously.Switching center can finish functions such as call proceeding, data forwarding, RRM and mobility management.
Access center: finish the access function of wireless network and wired core network, comprise data forwarding, Route Selection, switching path foundation etc.; Interface with other network also is provided, finishes exchange and control with other network.
Registration center: registration center is the database that is used for the wireless access subscriber management, and each user must register in registration center.Registration center is the mapping of air station user record IP address and air station identification code.
The device flag device: the device flag device is the database of the relevant air station device parameter of storage, realize to air station equipment discern, functions such as supervision, locking.
AUC: AUC is that authenticate wireless inserts user's identity and the functional entity that produces corresponding parameters for authentication.These parameters comprise random number, key etc.AUC carries out authentication to any user who attempts to network, have only validated user could Access Network in and obtain service.
Administrative center: administrative center is the functional entity that the network operator monitors and operates the whole network.
The charging center: charge to the voice communications versus data communications business that different brackets, different service quality require in the charging center.
The broadband wireless MAN protocol stack model as shown in Figure 2.(orthogonal frequency division multiplexing multiple access inserts the OFDMA pattern to the physical layer that defines by IEEE802.16 between air station and the base station, 2-11GHz) communicates with mac-layer protocol.Utilize between base station and the base station IEEE802.16 physical layer of directional antenna by IEEE802.16 definition (single carrier SC pattern, 10-66GHz) and PPP (the Point to Point Protocol) agreement that defines of IETF (Internet Engineer Task Force) communicate.Physical layer and mac-layer protocol by the IEEE802.3 definition between base station and the cable network communicate.Each functional entity in the cable network communicates by core I Pv6 network.In the protocol stack model of Fig. 2, the 3rd layer is divided into two sublayers.The RRM sublayer manages the Radio Resource that IEEE802.16 inserts part, comprises power control, channel allocation, authentification of user etc.IP handles Internet Protocol the sublayer, comprises the foundation of IP (v6) route, the foundation of MPLS label switched path, route querying and data forwarding etc.Be divided into mobile management sublayer, call manager sublayer and network operation sublayer more than three layers.The mobile management sublayer is supported the mobility of air station and is managed, and comprises inner switching, handover etc.The call manager sublayer is supported voice user's communication and is managed, and comprises call proceeding, QOS (Quality of Service, service quality) request, resource bid and release etc.The network operation sublayer provides support to Long-distance Control and the whole wireless MAN of maintenance.
In broadband wireless MAN system proposed by the invention, the IEEE802.16 base station is the nucleus equipment that network wireless inserts.The present invention requires the base station can support the voice communication and the reliable multimedia data communication of quality assurance, and have the control of good access control, power, mobile switching controls and a capacity extension ability, support the wireless access of IEEE802.16x series terminal, support route and tag path exchange between the base station, support is connected with core I Pv6 network, supports IPv6 and mpls protocol.The base station protocol stack structure as shown in Figure 3.The base station physical layer is supported IEEE802.16 PHY (OFDM OFDMA and single carrier SC pattern) and IEEE802.3 PHY.The base station data link layer is supported IEEE802.16 MAC, IEEE802.3 MAC and IETF ppp protocol.The base station network layer is supported mpls protocol, IP, IPv6 agreement and RRM agreement, and the various Radio Resources of RRM consultative management and control base station guarantee resources effective distribution and reliable recovery.On network layer, TCP/UDP host-host protocol and OSPF (Open Shortest Path First) Routing Protocol are supported in the base station, support label distribution LDP (Label Distribution Protocol) agreement, resource reservation RSVP-TE (Resouce Reserve Protocol extended for Traffic Engineering) agreement, mobile management signaling system, call manager signaling system, network operation signaling system and each application layer procotol.The management of mobile management signaling system is moved relevant work with terminal, comprise the data of processing from the portable terminal home agent, when new user moves and joins this base station, service specific convergence sublayer (the Service-specificConvergence Sub-layer of the MAC layer of mobile management system order IEEE802.16, CS) set up new connection, and corresponding QOS parameter is provided, participate in scheduling; When the user left, mobile management system notice wireless resource management was regained connection and the system resource that belongs to this portable terminal.Call manager signaling system transmitting-receiving and handle the signaling message of various voice communications realizes normally continuing and moving switchings of voice communication, and realizes rational resource reservation by wireless resource management, the service quality of conversing with assurance.The network management signaling system provides network operation management, safety management, operation and performance management, system change control, system maintenance and the needed communication function of fault recovery.
Fig. 4 is the broadband wireless MAN topological structure that class-of-service is provided that utilizes institute of the present invention extracting method to make up.Metro core net, base station and IP mobile telephone are all supported the IPv6 agreement; Base station and core net router (comprising couple in router) are also supported OSPF Routing Protocol, MPLS label switching protocol and RSVP-TE RSVP; Data link layer operation ppp protocol between base station and the base station, the bandwidth between the base station is divided into control bandwidth and service bandwidth, and control bandwidth is used for transmission network management and business control signaling, and service bandwidth is used for service data transmission.IEEE802.16-2004 and IEEE802.16e agreement are also supported in IP mobile telephone and base station.The function of switching center is finished in couple in router (adopting the MPLS router) and IEEE802.16 base station, for the IP packet is selected route, for voice flow is set up switching path, and will be transmitted to next hop router (comprising the base station) from voice or the data high-speed that IP mobile telephone transmits.Certificate server, registrar, management server, couple in router and base station are finished RRM jointly, as power control, access control, channel allocation, the mobile switching.Management server also is responsible for the equipment of whole network is carried out telemanagement, comprises system maintenance, fault recovery, user management etc.AAA (Authentication, Authorization andAccounting) server carries out authentication to voice on the network or data communication.The general data message that enters access base station and router is walked 3 layers of route, has the 2 layers of exchange that flow away of data message that QOS requires and voice.Certificate server, registrar, management server and aaa server are online at core I Pv6 according to certain policy distributed, communicate by letter by corresponding signaling system (comprising voice communication signaling system, mobile management signaling system and network operation signaling system etc.), finish coordinated control function.Exchange gateway provides the interface with other network (as PSTN, ISDN, GSM, 3G), finishes broadband wireless MAN and other internetwork call proceeding and exchange.
The user identification code of IP mobile telephone (as telephone number) is that predetermined fixed is distributed, and for example can be solidificated in the subscriber identification module.When IP mobile telephone is started shooting, at first carry out equipment identities authentication and authenticating user identification (certificate server and registrar participate in finishing), after authentication is passed through, IP mobile telephone from access base station (for example, the access base station of IP mobile telephone 1 is IEEE802.16 base station 1) locate to obtain an IPv6 address, then this address and the telephone number of oneself are registered to registrar, in registrar, set up the mapping of telephone number to current IP address.The initialization flow process that air station enters network as shown in Figure 5.
IEEE802.16 provides four kinds of dissimilar services: non-request grant service (Unsolicited Grant Service, UGS), real time polling service (Real-time PollingService, rtPS), non real-time poll services (Non-real-time Polling Service, nrtPS) and the service of doing one's best (Best Effort, BE).The UGS service is used for fixing the real time data stream of bit rate, as IP phone.The RtPS service is used for the real time data stream of non-constant bit rate, as the MPEG video.NrtPS is used for the non-real-time data stream of non-constant bit rate, transmits as ftp file.BE service is used to the business that do not have special QOS demand, only need do one's best.The business of the different grades of service and QoS requirement is come the Request System resource by these four kinds of dissimilar services, and dispatch system resource according to the QOS parameter of air station request the base station, thereby realizes class-of-service.
When the telephone number of 1 pair of IP mobile telephone 2 of IP mobile telephone is called out, at first carry out call class authentication, after the aaa server authentication and obtaining the authorization, to the current IP address of registrar inquiry IP mobile telephone 2.After obtaining the IP address of IP mobile telephone 2, IEEE802.16 base station 1 starts pathfinding mechanism and resource reservation mechanism immediately, set up one from IP mobile telephone 1 to IP mobile telephone 2 satisfy the route that specific QOS requires, set up two layers of switching path by mpls protocol simultaneously.After switching path was built up, mobile phone 1 and mobile phone 2 began conversation, and aaa server starts charging.Behind the end of conversation, the wireless and cable resource that this conversation is reserved is released.Voice communication flow process in the broadband wireless MAN as shown in Figure 6.
The present invention utilizes the IEEE802.16 Radio Transmission Technology to make up the broadband wireless MAN with class-of-service ability; Use is based on the broadband wireless city field network system structure of IEEE802.16 agreement, the broadband wireless MAN protocol stack model, broadband wireless MAN base station protocol stack structure and MAN topological structure, on the IEEE802.16 base station, increased inter-base station interface, allow multi-hop wireless connection between the base station, the wireless coverage area of expansion MAN, on MAN, adopt RSVP to guarantee professional institute requested service quality, adopt mpls protocol to set up two layers of switching path, the business that requires for high-grade high QOS provides support, four kinds of dissimilar services that utilize IEEE802.16 to provide realize the class-of-service request, utilize two layers of exchange to guarantee good voice call quality.
Four kinds of different COS that the present invention utilizes IEEE802.16 to provide are supported class-of-service, make different business utilize different priority to transmit in network; The quality of service requirement that utilizes QOS scheduling mechanism that IEEE802.16 provides and the resource reservation mechanism on the MAN to guarantee the grade business; Utilize base station and the router of supporting MPLS to provide good QOS to support, the business of high priority high quality-of-service requirement is transmitted by two layers of label exchange, and the business of the low quality of service requirement of low priority is transmitted by three layers of routing forwarding.
Description of drawings
Fig. 1 is the broadband wireless city field network system structure chart.
Fig. 2 is broadband wireless MAN protocol stack model figure.
Fig. 3 is base station protocol stack structure figure.
Fig. 4 is the broadband wireless MAN topology diagram.
Fig. 5 is the air station initialization flowchart.
Fig. 6 is the voice communication flow chart.
Embodiment
The broadband wireless MAN construction method of class-of-service is provided, and the initialization flow process that IEEE802.16 air station wherein enters network is as follows:
Step S1: set up Radio Link between air station and the base station and be connected;
Step S2: air station is registered to broadband wireless MAN, obtains the IP address;
Step S3: air station is carried out the configuration of Virtual network operator requirement, and sets up relevant pre-connection.
The treatment step of each incident is as follows among Fig. 5: (air station initialization flow process)
S5.1: when air station enters network, by the DCD and the DL_MAP message of base stations detected broadcasting, obtain with down link (base station is to the Radio Link of air station) synchronously;
S5.2: judge whether that success is synchronized to down link, promptly whether receive effective DCD and DL_MAP message continuously, if enter S5.3; Otherwise, forward S5.1 to, attempt being synchronized to next down link;
S5.3:, obtain uplink parameter by the UCD and the UL_MAP message of base stations detected broadcasting;
S5.4: judge whether that success obtained uplink parameter, promptly whether receive effective UCD and UL_MAP message continuously, and the parameter in the message is fit to air station, if enter S5.5; Otherwise, forward S5.1 to, attempt being synchronized to next down link;
S5.5: start ranging process, mutual by RNG-REQ and RNG-RSP message and base station, associated transport parameter (as transmitted power) is adjusted, and set up basic (Basic) between air station and base station and be connected with primary (Primary) and be connected, (management) that these two connections are used to transmit between air station and base station controls signaling;
S5.6: judge whether to complete successfully parameter adjustment, promptly whether receive the RNG-RSP message that is designated SUCCESS, if enter S5.7; Otherwise, forward S5.1 to, attempt being synchronized to next down link;
S5.7: after range finding is finished, start basic capability negotiation process, mutual by SBC-REQ and SBC-RSP message with the base station, the coordination ability parameter collection that both sides supported;
S5.8: judge whether to complete successfully basic capability negotiating, whether the base station enables the support of the basic capacity parameter set that air station is asked, and whether receives that promptly status indicator is the SBC-RSP message of OK, if enter S5.9; Otherwise, forward S5.1 to, attempt being synchronized to next down link;
S5.9: start authentication and key exchange process, certificate server participates in finishing this process;
S5.10: judge whether by authentication, if, forward S5.12 to by authentication; Otherwise, enter S5.11;
S5.11: air station by authentication, is not prohibited from entering network;
S5.12: air station is finished registration process to network registry by REG-REQ and REG-RSP interacting message, consults IP version number, sets up less important (Secondary) and connects, and this connection is used for transmitting between network and manageable air station management and controls signaling;
S5.13: judge whether to succeed in registration, judge whether promptly to receive that status indicator is the REG-RSP message of OK, if enter S5.14; Otherwise, forward S5.1 to, attempt being synchronized to next down link;
S5.14: start the IP connection and set up process, obtain the IP address, registrar participates in finishing this process;
S5.15: judge whether successfully to obtain the IP address, if, telephone number is registered to registrar to the mapping of current IP address, enter S5.16 then; Otherwise, forward S5.1 to, attempt being synchronized to next down link;
S5.16: start-up time synchronizing process and configuration file acquisition process, management server participates in finishing this process;
S5.17: whether judgement is successful with configuration synchronously, whether receives that promptly status indicator is the response message of OK, if enter S5.18; Otherwise, forward S5.1 to, attempt being synchronized to next down link;
S5.18: start pre-connection and set up process, finish pre-connection by DSA-REQ and DSA-REP message and set up, pre-connection is used to transmit the service flow that Virtual network operator provides in advance;
S5.19: judge whether pre-connection sets up success,, wait for customer incident if air station enters holding state; Otherwise, forward S5.1 to, attempt being synchronized to next down link;
The broadband wireless MAN construction method of class-of-service is provided, and the voice communication flow process between the IEEE802.16 air station wherein is as follows:
Step S1: call initiator application control bandwidth is used for the transport voice communications signaling;
Step S2:, be used for transferring voice stream by the air station application service bandwidth of authentication;
Step S3: the IP address of inquiry called party, start route and resource reservation process, set up label switched path;
Step S4: called party is set up the wireless connections with access base station by authentication;
Step S5: start communication process;
Step S6: end of conversation discharges the shared system resource of this conversation.
The treatment step of each incident is as follows among Fig. 6: (voice communication flow process)
S6.1: air station is received dialer event, will be wailed sign indicating number and sort out (urgent call class, ordinary call class, special calling class), determines the grade of service and QOS parameter according to affiliated classification;
S6.2: to base station application control bandwidth, the grade of service of control bandwidth and QOS parameter are decided according to the requirement of voice communication signaling system;
S6.3: bandwidth request is received in the base station, by scheduler module, for air station is distributed desired system resource;
S6.4: air station judges whether to obtain the bandwidth of being asked, and promptly whether has set up a control connection (by connection identifier (CID CID sign) with the certain quality of service binding, if enter S6.5; Otherwise, forward S6.21 to;
S6.5: air station sends authentication request to aaa server;
After the S6.6:AAA server was received authentication request, the service rights of using of main side of exhaling of inquiry and called party exhaled the air station return authentication to reply to the master then;
S6.7: air station judges this time to call out whether pass through authentication, if enter S6.8; Otherwise, forward S6.21 to;
S6.8: air station is applied for service bandwidth to the base station, and the grade of service of service bandwidth and QOS parameter are for sorting out the determined relevant parameter in back;
S6.9: after the service bandwidth request is received in the base station,, distribute the system resource that meets the demands for air station by scheduler module;
S6.10: air station judges whether service bandwidth distributes successful, promptly whether set up a business with the certain quality of service binding and be connected, if enter S6.11; Otherwise, forward S6.21 to;
S6.11: air station is to the called party demand signalling that makes a call;
S6.12: after the call request signaling is received in the base station, wailed the current IP address of sign indicating number to the registrar inquiry;
S6.13: registrar is searched and is wailed the pairing IP of sign indicating number address, then purpose IP address is returned to the access base station of the main side of exhaling;
S6.14: after the response message that comprises purpose IP address is received in the base station, start route querying and resource reservation process, set up the label switched path between inlet base station (access base station of the main side of exhaling) and the outlet base station (access base station of called party), and the mapping of setting up professional CID of connection and label switched path;
S6.15: network facet judges whether successfully resource reservation and label switched path are set up, if enter S6.16; Otherwise, forward S6.21 to;
S6.16: transmit the call request signaling inlet base station to the outlet base station, and outlet base station notice called party has call request to arrive and requires called party to pass through authentication, to finish the subsequent voice calls process;
S6.17: called party by the authentication and obtain desired bandwidth after, the mapping of setting up professional CID and label switched path; Like this, just set up two layers of switching path between main side of exhaling and the called party, voice flow will transmit on this paths;
S6.18: the outlet base station sends ring-back tone to the master side of exhaling, and called party initiates to reply;
S6.19: after the main side of exhaling hears the called party off-hook, the conversation beginning, aaa server starts the charging to this conversation;
S6.20: behind the end of conversation, network is released to this time calls out institute's distributed system resources (comprising Radio Resource and cable resource), enters holding state then, waits for the arrival of user's next event;
S6.21: owing to do not finish normal call proceeding and resource allocation process, call announcement failure this time.