CN1949747A

CN1949747A - Two layer network architecture system, implementing method and head compression and nondestructive transference method thereof

Info

Publication number: CN1949747A
Application number: CNA2006100810748A
Authority: CN
Inventors: 王艳红
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2005-10-14
Filing date: 2006-05-23
Publication date: 2007-04-18
Anticipated expiration: 2026-05-23
Also published as: CN100574273C

Abstract

The invention discloses a two-layer network structured system and implementing method and the head compressing and lossless migrating methods thereof. Two layers of nodes comprise edge radio station (ERS) and IP access gateway (IAGW), where ERS is formed by cominging NodeB in a three-layer network structured telecom system with radio network controller (RNC). In various protocol entities on the two layers of nodes, PDCP'entity on IAGW comprises head compression module and RLC' protocol entity on ERS comprises lossless migrating module. That is to say, head compression module in PDCP entity moves up to IAGW; lossless migrating module in PDCP entity moves down to radio link control protocol entity on ERS. And the invention also discloses head compression method and lossless migrating method executed in the improved network structure. In the two-layer node structure of network evolution, the invention adopts new user plane protocol stack and can raise service data transmitting efficiency.

Description

Two layer network architecture system, implementation method and head compression thereof, lossless migration method

Technical field

The present invention relates to a kind of telecommunication system, relate in particular to implementation method and the head compression and the lossless migration method of a kind of telecommunication system of two-layer node network architecture, this system.

Background technology

Universal Mobile Telecommunications System (UMTS) is the 3-G (Generation Three mobile communication system) that adopts Wideband Code Division Multiple Access (WCDMA) (WCDMA) air interface technologies, also the UMTS system is called the WCDMA communication system usually.The UMTS system has adopted and the similar structure of second generation mobile communication system, comprises Radio Access Network (RAN, Radio Access Network) and core network (CN, Core Network).Wherein, Radio Access Network is used to handle all and wireless function associated, and CN handles that all voice calls are connected with data in the UMTS system, and the exchange of realization and external network and routing function.CN is from being divided into circuit commutative field (CS, Circuit Switched Domain) and packet-switched domain (PS, PacketSwitched Domain) in logic.UTRAN, CN and subscriber equipment (UE, User Equipment) have constituted whole UMTS system together.Its system configuration as shown in Figure 1.

UTRAN is a land radio access web, and it comprises one or several RNS (RNS, Radio NetwoRK Subsystem).A RNS is made up of a radio network controller (RNC) and one or more base station (NodeB).Interface between RNC and the CN is the Iu interface, and NodeB is connected by Iub interface with RNC.In UTRAN inside, interconnected by Iur between the radio network controller (RNC), Iur connects or connects by transmission network by the direct physical between the RNC.RNC is used for distributing and is attached thereto with control or the Radio Resource of relevant NodeB.NodeB then finishes the conversion of the data flow between Iub interface and the Uu interface, also participates in a part of RRM simultaneously.The structure of UTRAN is as shown in Figure 2:

NodeB is the base station of WCDMA system, comprises radio receiving-transmitting unit and Base-Band Processing parts.By the Iub interface and the RNC interconnection of standard, mainly finish the processing of Uu interface physical layer protocol.Its function comprises spread spectrum, modulation, chnnel coding and despreading, demodulation, channel-decoding, also comprises the functions such as mutual conversion of baseband signal and radiofrequency signal.

RNC is a radio network controller, is used to control the Radio Resource of UTRAN, mainly finishes functions such as connection foundation and disconnection, switching, the merging of grand diversity, RRM control.Specific as follows:

(1) executive system information broadcast and system's access control function;

(2) switching and RNC migration mobile management functions such as (Relocation also can be called reorientation);

(3) RRM and controlled function such as grand diversity merging, power control, radio bearer distribution.

Use the Iu series interfaces among the UTRAN, comprised Iu, Iur and Iub interface.

The Iu interface is the interface that connects UTRAN and CN.Be similar to the A interface and the Gb Interface of gsm system.The Iu interface is the standard interface of an opening.Iu interface control plane agreement is RAN application protocol (RANAP, RAN Application Protocol), and user plane protocol is GPRS Tunnel Protocol (GTP, GPRS Tunneling Protocol).

The Iur interface is the interface that connects between the RNC, and the Iur interface is the distinctive interface of UMTS system, is used for the mobile management to the RAN travelling carriage.When carrying out soft handover between different RNC, all data of travelling carriage all are to pass to candidate RNC by the Iur interface from the RNC that is working.Iur is open standard interface.Iur interface control plane agreement is RNS application protocol (RNSAP, RNS ApplicationProtocol), and user plane protocol is Iur Frame Protocol (Iur FP, Iur Frame Protocol).

Iub interface is the interface that connects NodeB and RNC, and Iub interface also is the standard interface of an opening.Iub interface chain of command agreement is that NodeB application protocol (NBAP, NodeB Application protocol) user plane protocol is Iub Frame Protocol (Iub FP, Iub Frame Protocol).

Employed user's face and chain of command protocol stack be as shown in Figure 3 among the UTRAN when the UMTS network service for the user.

The function that Radio Resource control (RRC) agreement realizes among Fig. 3 comprises: the information that broadcasting is provided by Non-Access Stratum; broadcast the information relevant with Access Layer; set up; a RRC who keeps and discharge between UE and the UTRAN connects; set up; reshuffle and releasing wireless loading; distribute; reshuffle and discharge and be used for the Radio Resource that RRC connects; RRC connects the locomotive function management; for higher layer protocol data units (PDU) routing by; the control of requested service quality (QoS); the UE measurement reports and reports control; exterior ring power control is encrypted control, slow dynamic channel allocation; paging; initial cell is selected and gravity treatment under the idle pulley, and up link DCH goes up the arbitration of Radio Resource, RRC message integrity protection and CBS control.

The function of Radio Link control (RLC) agreement comprises: cut apart and recombinate, the transmission of user data is filled in series connection, error detection, send higher layer protocol data units (PDU) according to the order of sequence, duplicate detection, Flow Control, non-authentication data transfer mode sequence number is checked, protocol error detects and recovers, and encrypts, and hangs up and restore funcitons.Rlc protocol provides TM, UM and three kinds of data-transmission modes of AM.TM is the transparent mode transmission, this pattern is used fixing SDU size, and is higher to delay requirement, is generally used for transmitting voice service or signaling, UM is the unacknowledged mode transmission, this pattern is used variable SDU size, and is also higher to delay requirement, is generally used for business such as transport stream medium, AM is the answer-mode transmission, this pattern is not high to delay requirement, but very high to error rate requirement, is generally used for transmitting data services such as WWW.

The function of medium access control (MAC) agreement comprises: the mapping between logic channel and the transmission channel, for each transmission channel is selected suitable transformat, processed between the UE data flow, adopt the processed of dynamically pre-arrangement method between the UE, processed between the data flow of the last several users of DSCH Downlink Shared Channel (DSCH) and FACH, the sign of UE on the Common transport channel, with high-rise PDU multiple connection is the transmission block that sends physical layer by transmission channel to, and will be high-rise PDU from the transmission block multiple connection of physical layer by transmission channel, traffic carrying capacity detects, the dynamic transmission channel type switches, and transparent RLC encrypts, and the access service rank is selected.

Packet data polymerized agreement (PDCP) sublayer function: send with receiving entity in carry out respectively the header suppression of IP traffic and decompression (as, the TCP/IP of IPv4 and IPv6 and the compression of RTP/UDP/IP head), header suppression has RFC2507 and two kinds of algorithms of RFC3095, and header compression method is corresponding to the combination of particular network layer, transport layer or upper-layer protocol; Transmitting user data, the PDCP service data unit (PDCP-SDU) that Non-Access Stratum is sent here is forwarded to rlc layer, and a plurality of different radio bearers (RB) are multiplexed into same RLC entity; For radio bearer safeguards that the PDCP sequence number is to support the lossless migration of SRNS Serving Radio Network Subsystem (SRNS).The business that the PDCP sublayer uses control sub layer of wireless link (RLC) to provide.

Below with reference to Fig. 4, a kind of existing two-layer node evolution architecture is described.

Above-described existing framework has a lot of shortcomings, such as, because signaling and data all must be transmitted between UE, NodeB, RNC and CN, the node number of process numerous, the time delay that causes handling and transmit is bigger, the possibility that the while transfer of data is made mistakes increases along with increasing of node number, and increasing of number of retransmissions also caused the time delay increase, reduced the efficient of system.The complexity of protocol layer has caused time delay and treatment effeciency problem too.These problems all can have a strong impact on the speed of high-speed data service, make the QoS of high-speed data service to be protected.

In order to reduce of the influence of existing Radio Access Network to QoS, simultaneously also in order to improve the efficient that Radio Access Network and core-network resources are used, the method that much addresses this problem has appearred, mainly be moving down with Radio interface protocols stack or user face protocol stack, protocol stack is moved on on the NodeB, the Radio interface protocols stack makes the reaction time shorten near eating dishes without rice or wine like this, has improved data transmission performance.The minimizing of node number simultaneously also preferably resolves propagation delay time and treatment effeciency problem.

In 3GPP, each manufacturer is all at active research Long Term Evolution (LTE, Long TermEvolution) at present, and the purpose of LTE provides a kind of network cheaply that can reduce time delay, raising user data rate, improved power system capacity and covering.It has proposed only to use PS territory business, and bearer network all is the IP carrying, and voice use the VOIP business in PS territory.LTE proposes a series of targets of 3G evolution, is some of wherein relatively giving prominence to below:

● significantly improve peak data rate, such as down link 100Mbps and 5 up link 0Mbps;

● realize that the Radio Access Network be lower than 10ms postpones (user plane subscriber equipment-UE);

● significantly reduce chain of command and postpone, comprise as far as possible beginning to exchange subscriber panel data (not comprising that the down link paging postpones) from the preemption state with time less than 100ms;

● (OPEX) (comprising the backhaul cost) paid in reduction Capital expenditure (CAPEX) and operation;

● realize from Rel-6UTRA wave point and the ground evolution of architecture economical and efficient;

● support dissimilar business efficiently, particularly from the business in PS territory, such as VOIP and presence service.

Along with the minimizing of node number and the disappearance in CS territory, need to consider distributing rationally again of a kind of evolution architecture and protocol layer.

In current LTE architecture evolution project, a kind of popular scheme is the two-layer node framework.As shown in Figure 4, this framework is made up of IAGW and ERS two-layer node.ERS is the Node B of evolution, has most of function of former RNC, and takes new physical-layer techniques, and such as OFDM, IAGW has the function of part SGSN and the function of former GGSN.

In addition, also has a kind of existing two-layer node evolution architecture, as shown in Figure 5.Under this framework, the RNC in the Access Network is divided into user's face and chain of command, adopts Iub Flex and Iu Flex interface, and core net can adopt a node layer or two-layer node.

More than two kinds of existing evolution architecture shortcomings be, some framework forms are only proposed, promptly reach purposes such as reducing time delay, do not have concrete function and divide and describe in detail, more do not relate to the heavily distribution of the concrete configuration and the function of protocol layer by reducing the node number.

Summary of the invention

The object of the present invention is to provide a kind of telecommunication system and its implementation, this system adopts a kind of new user face protocol stack based on the framework of two-layer node, and the back will be described the function of each protocol entity in the protocol stack in detail.

Another object of the present invention is to provide a kind of head compression method based on above-mentioned telecommunication system.To move on to the IAGW side on the compression module, fulfil the head compression ahead of schedule, saved the transmission bandwidth between IAGW and the ERS, reduced the propagation delay time and the transmission package loss of bag.

Another object of the present invention is to provide a kind of lossless migration method based on above-mentioned telecommunication system.Radio interface protocols stack or user face protocol stack are moved down on the NodeB, and the Radio interface protocols stack makes the reaction time shorten near eating dishes without rice or wine like this, has improved data transmission performance.And an importance improving data transmission performance is exactly the characteristic that adapts to evolution architecture, optimizes existing signaling process.

On the one hand, a kind of telecommunication system of two-layer node network architecture is provided, this two-layer node comprises wireless base station, edge (ERS) and IP IAD (IAGW), wherein, wireless base station, edge (ERS) is that interior base station (NodeB) node of three-layer network framework telecommunication system and wireless network control (RNC) node form in conjunction with the back.In each protocol entity on this two-layer node, a protocol entity comprises a compression module, and another protocol entity comprises the lossless migration module.

In said system, the packet data polymerized agreement on the IP IAD (IAGW) (PDCP ') entity comprises a compression module.

Further comprise on the above-mentioned IP IAD (IAGW): GPRS Tunnel Protocol/User Datagram Protoco (UDP)/IP (GTP/UDP/IP) entity that links to each other with packet data polymerized agreement (PDCP ') entity; The L2 physical layer protocol entity that links to each other with GPRS Tunnel Protocol/User Datagram Protoco (UDP)/IP (GTP/UDP/IP) entity; The L1 physical layer protocol entity that links to each other with L2 physical layer protocol entity.

In said system, Radio Link on wireless base station, edge (ERS) control (RLC ') protocol entity comprises the lossless migration module.

Radio Link on the wireless base station, above-mentioned edge (ERS) control (RLC ') protocol entity further comprises all functions module in Radio Link control (RLC) entity on wireless network control (RNC) node in the three-layer network framework telecommunication system.

Further comprise on the wireless base station, above-mentioned edge (ERS): medium access control (MAC) protocol entity that links to each other with Radio Link control (RLC ') protocol entity; The L1 physical layer protocol entity that links to each other with medium access control (MAC) protocol entity.

Above-mentioned each protocol entity comprises, all functions module in the respective protocol entity on wireless network control (RNC) node in the three-layer network framework telecommunication system.

On the other hand, a kind of implementation method of telecommunication system two-layer node network architecture is provided, this two-layer node comprises wireless base station, edge (ERS) and IP IAD (IAGW), wherein, wireless base station, edge (ERS) node is that interior base station (NodeB) node of three-layer network framework telecommunication system and wireless network control (RNC) node form in conjunction with the back.The method comprising the steps of: A, on wireless base station, edge (ERS) node, form with three-layer network framework telecommunication system on wireless network control (RNC) node each protocol entity distinguish after corresponding protocols entity, remove packet data polymerized agreement (PDCP) entity wherein; Compression module on interior wireless network control (RNC) node of B three-layer network framework telecommunication system in packet data polymerized agreement (PDCP) entity moves on on the described two-layer node, form a protocol entity, simultaneously, lossless migration module in this packet data polymerized agreement (PDCP) entity moves on on the described two-layer node, forms another protocol entity.

Above-mentioned steps B further comprises: move to IP IAD (IAGW) on the compression module in this packet data polymerized agreement (PDCP) entity, form packet data polymerized agreement on this IP IAD (PDCP ') entity.

Above-mentioned steps B further comprises: the lossless migration module in this packet data polymerized agreement (PDCP) entity is displaced downwardly to the radio link control entity on the wireless base station, edge (ERS), and the Radio Link control after the formation increase function (RLC ') protocol entity.

Also have on the one hand, provide a kind of compression module to carry out the method for head compression.Move on the compression module on wireless network control (RNC) node in packet data polymerized agreement (PDCP) entity after packet data polymerized agreement on the IP IAD (IAGW) (the PDCP ') entity, this method comprises: A, wireless base station, edge (ERS) utilize the compressed configuration parameter of preserving in the memory of IP IAD (IAGW) to carry out the selection of header compression algorithm and the configuration and the negotiation of compressed parameter; B, set up a compressed context between the compression module according to the feature of data flow separating on compression module on the IP IAD (IAGW) and subscriber equipment (UE) by selected compression algorithm; C, this compression module and this are separated a compression module and according to a compressed context of being set up packet are compressed in succession and decompress.

Above-mentioned steps A further comprises: wireless base station, edge (ERS) extracts a compressed configuration parameter and preserves from the instruction that IP IAD (IAGW) is sent, and passes through land radio access web (UTRAN) then to subscriber equipment (UE) delivery header compression parameters; After the compressed parameter that subscriber equipment (UE) analysis is received, carry out the configuration and the negotiation of parameter to separating a compression module.

Above-mentioned steps B further comprises: the data transmit-receive two ends utilize unpressed initial data packets to set up the context of data flow.

Above-mentioned steps C further comprises: the packet after the compression arrives wireless base station, edge (ERS) via the tunnel encapsulation and the IP route transmission of GPRS Tunnel Protocol user face (GTP-U); Wireless base station, edge (ERS) is separated the packet of receiving and is handed to Radio Link control (RLC ') protocol entity after the tunnel encapsulation, is sent to subscriber equipment (UE) by air interface by this protocol entity; Packet data polymerized agreement on the subscriber equipment (UE) (DPCP ') decompression module decompresses to the packet of receiving according to the context of being set up.

Compression among the above-mentioned steps C is that the above part of GPRS Tunnel Protocol user face (GTP-U) layer carried out.

Last aspect provides a kind of lossless migration module to carry out the method for lossless migration.Lossless migration module on wireless network control (RNC) node in packet data polymerized agreement (PDCP) entity is displaced downwardly to after Radio Link control on the wireless base station, edge (ERS) (the RLC ') protocol entity, this method comprises: A, during the RLC service data unit transmits, on the transmitting terminal with receiving terminal on the RLC sequence number of Radio Link control (RLC ') each self refresh self maintained of protocol entity; B, when the lossless migration module is carried out context transfer from service edge wireless base station (SERS) to object edge wireless base station (TERS), service edge wireless base station (SERS) obtains RLC service data unit sequence number from the Radio Link of this locality control (RLC ') protocol entity, sends to object edge wireless base station (TERS) by IP IAD (IAGW); The RLC sequence number that exchange is safeguarded separately between C, subscriber equipment (UE) and object edge wireless base station (TERS) confirms to send but also is not received the reception condition of the RLC service data unit of affirmation; D, after reorientation is finished, data send from first not confirmed RLC service data unit.

Above-mentioned steps A further comprises: when receiving a complete service data unit, the progressively increase reception RLC sequence number of its maintenance of Radio Link on receiving terminal control (RLC ') protocol entity, the control of the Radio Link on transmitting terminal simultaneously (RLC ') protocol entity sends acknowledge message.

Above-mentioned steps A further comprises: when receiving acknowledge message, the progressively increase transmission RLC sequence number of its maintenance of Radio Link on transmitting terminal control (RLC ') protocol entity is deleted all protocol Data Units corresponding with this service data unit in the retransmission buffer simultaneously.

Above-mentioned steps B further comprises: service edge wireless base station (SERS) directly obtains RLC service data unit sequence number from the Radio Link of this locality control (RLC ') protocol entity by primitive.

Above-mentioned steps C further comprises: exchanged separately after the RLC sequence number of safeguarding, subscriber equipment (UE) and object edge wireless base station (TERS) notify the frame number of local wireless control (RLC ') the current RLC service data unit that will send of protocol entity replacement separately.

Above-mentioned steps C further comprises: subscriber equipment (UE) and object edge wireless base station (TERS) are separately by primitive notice local wireless control (RLC ') protocol entity.

The present invention has many advantages and characteristics, below is major advantage wherein.

The wireless communication system that the present invention proposes under the two-layer node framework of network evolution, has adopted new user face protocol stack, can improve service data transmitting efficiency, reduces propagation delay time.These beneficial effects are embodied in:

1) moves on to the IAGW side on the compression function, fulfil the head compression ahead of schedule, saved the transmission bandwidth between IAGW and the ERS, reduced the propagation delay time and the transmission package loss of bag.

2) move on to the IAGW side on the compression function, IAGW does not need to shift the context (Context) of compression as anchor point in handoff migration, be convenient to quick handoff migration.

3) moving down of air protocol stack reduced the influence of propagation delay time to user QoS, improved efficiency of transmission.

4) node number and number of ports all significantly reduce, and have reduced processing expenditure and transport overhead, have reduced time delay and have improved efficient.

5) use the Iu-flex interface between ERS and the IAGW, avoided Single Point of Faliure effectively, be convenient to realize load sharing simultaneously.

6) this scheme has been reused existing protocol to greatest extent, and the UTRAN framework can smooth evolution.

The head compression method based on above-mentioned communication system that the present invention proposes will move on to the IAGW side on the compression function, fulfil the head compression ahead of schedule, has saved the transmission bandwidth between IAGW and the ERS, has reduced the propagation delay time and the transmission package loss of packet.

The lossless migration method based on above-mentioned communication system that the present invention proposes is based on a kind of network evolution architecture of two-layer node.Because new two-layer node network structure and user-plane protocol all obtained optimization, so use migration flow process provided by the invention, can improve the efficient of UE switching flow, reduces to move break period.

Description of drawings

Fig. 1 is the system configuration schematic diagram of UMTS;

Fig. 2 is the schematic network structure of UTRAN;

Fig. 3 illustrates UTRAN chain of command and user face protocol stack;

Fig. 4 illustrates a kind of existing two-layer node network evolution architecture;

Fig. 5 illustrates another kind of existing two-layer node network evolution architecture;

Fig. 6 illustrates according to evolution architecture user face protocol stack of the present invention;

Fig. 7 is according to the described lossless migration flow chart of one embodiment of the invention.

Embodiment

Below with reference to Fig. 6, the telecommunication system of the two-layer node network architecture of the present invention's proposition is described.

Network side has only ERS and this two-layer node of IAGW.From the wave point user face protocol stack, ERS has physical (L1), MAC layer, RLC ' layer, and IAGW has new PDCP ' layer, GPRS Tunnel Protocol/User Datagram Protoco (UDP)/IP (GTP/UDP/IP) layer, L2 and L1 physical layer.The Iu-flex interface is the interface of ERS and IAGW, uses the IP transmission.

Wherein physical layer and the MAC layer of L1 layer and the similar substantially existing Rel6 of MAC layer.L1 is the physical layer of evolvement network, can use OFDM, and technology such as MIMO improve the spectrum efficiency of eating dishes without rice or wine.MAC is the MAC layer of Radio interface protocols stack, have entities such as MAC-d, MAC-c/sh, MAC-b, MAC-hs, MAC-es and MAC-e, substantially on the basis of Rel6, there are not much changes, different is to be become by original entity in RNC and Node B dispersion all to concentrate on ERS, has accelerated the dispatching of eating dishes without rice or wine.

Reciprocity RLC ' layer among network side and the UE is finished the function of rlc layer in the past, because original PDCP layer disappears, the PDCP sequence number maintenance function of user data transmission that the PDCP layer is responsible for and support lossless migration moves down into RLC ' layer simultaneously.RLC ' the function that proposes among the present invention is a logic function, can merge with other protocol entity.

The GTP/UDP/IP layer on the IAGW node and the function of L2/L1 layer are identical with the function of existing protocol layer.PDCP ' is new protocol layer, and function and interface are different from former PDCP, a main compression function of being responsible for.

Because ERS is in last kilometer, often uses low speed chain circuit, so the bandwidth between the ERS is narrower.With this understanding, do not have Iur or similar interface between the ERS, the migration between the ERS by and IAGW between the Iu interface carry out message and forwarding of data.

Also because ERS is in last kilometer, the Iu link is away from operator's control range.Randomly, use encryption technologies such as IPsec in the Iu combination of interfaces, guarantee the safety of Iu interface data transmission.

When RLC ' is configured to submit with affirmation mode in proper order, RLC ' will support lossless migration, and the configuration of RLC ' is controlled by Radio Resource control (RRC) agreement of chain of command.In order to support lossless migration, the functional description that RLC ' increases is as follows:

1) RLC ' entity will be safeguarded the sequence number of RLC service data unit (RLC SDUs) according to the identical rule of agreement [1] 5.6.1.1.

2) RLC ' sends and receiving entity will be kept according to the identical rule of agreement [1] 5.6.1.2 and make a start and the sequence number of receiving end RLC SDUs synchronous.

3) when carrying out the SRNS reorientation, sequence number exchanges between UE and ERS, and these sequence numbers are used to confirm that RLC SDUs has sent but also not being received end confirms in agreement [1] 5.6.1.3 identical description is arranged.After reorientation was finished, data sent from first not confirmed RLC SDU.

4) when the ERS reorientation, the RLC ' entity of UE and the RLC ' entity of ERS will exchange following information:

-UE will send to the sequence number DL-Receive RLC SN of the descending reception of the next expectation of ERS;

-ERS will send to the sequence number UL-Receive RLC SN of the up reception of the next expectation of UE.

5) when the ERS reorientation, former ERS will transmit following data to target ERS by IAGW:

The UL_Receive RLC SN (up reception RLC sequence number) of the next RLC SDU that-expectation receives from UE;

The descending transmission RLC sequence number (DL_SendRLC SN) of the RLC SDU that-first transmission but do not have is confirmed;

-send but not have the RLC SDUs of affirmation and their DL_Send RLC SNs;

-there is not the RLC SDU that sends.

Describe the function of the compression module in the PDCP ' entity below according to one embodiment of the present of invention, this function realization flow is as follows:

The first step, the configuration of compressed parameter and negotiation.For RFC2507 or RFC3095 agreement, the configuration parameter that its compression is adopted comprises CID_INCLUSION_INFO, MAX-CID, PROFILES or the like, and configuration parameter is kept in the memory of IAGW after IAGW starts.When the Iu-flex interface is set up RAB (RAB), if startup compression algorithm, then carry PDCP '-Info message elements in the RABASSIGNMENT of RANAP REQUEST message, PDCP '-Info message elements is carrying the needed configuration parameter CID_INCLUSION_INFO of compression algorithm, MAX-CID, PROFILES etc.The purpose of carrying PDCP '-Info information unit is which kind of compression algorithm indication ERS should set up, and disposes the parameter of every kind of compression algorithm.

Therefore, RAB ASSIGNMENT REQUEST message need increase PDCP '-Info information unit in its message elements.

ERS is kept at this locality with the compressed parameter that carries in its PDCP '-Info information unit after receiving RAB ASSIGNMENT REQUEST message, then the layoutprocedure of employing and existing the duplicate compressed parameter of compression module.This process is specific as follows: compressed parameter is notified UE by RB setup process by UTRAN.UE will be provided with profiles, the ability of comparative parameter and the support of self etc. according to these parameter configuration PDCP entity.After UE is receiving RB setup and is analyzing the PDCP-info information unit, to compare with the value of UE_CAPABILITY_TRANSFERRED variable storage, for example, if the parameter MAX_CID among the discovery PDCP-info is greater than himself ability (as the maximum quantity Maximum number of ROHC context sessions of ROHC context session), UE will trigger UE CAPABILITY INFORMATION process, the Maximum number ofROHC context sessions of its support is fed back to UTRAN, to send capability information of user facility after UTRAN confirms this value and confirm that (UE CAPABILITY INFORMATION CONFIRM) message is to UE, after UE receives this message, will be updated to the last value that sends to UTRAN in this RRC connection to the value of UE_CAPABILITY_TRANSFERRED.Algorithm and the parameter configuration process of UE have been finished thus.

The negotiation of compressed parameter is also adopted and existing the same negotiation flow process, promptly realizes by ROHC in-band signalling (ROHC bag and feedback packet).

Second step, the foundation of compressed context (Context).When RAB carrying and RB carry all set up and finish the signaling process process after, will begin data transmission procedure.If initial data stream is upstream, then initiate the process that head compression Context sets up by UE; If initial is downstream data flow, then initiates head compression Context and set up process by IAGW.Head compression Context dynamically forms between compressor reducer and decompression machine, the packet of the original transmission of a new stream does not compress, two ends utilize initial packet to set up data flow context, this stream context comprises the static fields value in packet header and the information such as changing pattern of field value, after in case stream context sets up, compressed header packet to greatest extent just.In certain period of time, such as when mistake is recovered, need to send incompressible bag with flow-reconstituted context, after finishing, reconstruction just gets back to compact model.The foundation of Context will be set up according to the feature of various flows by the compression algorithm of selecting.

The 3rd step, compression and decompression.After PDCP ' layer receives a data flow from the upper strata, PDCP ' compressor reducer (supposing at IAGW) begins compressed package according to the Context that sets up, compression is that the part more than the GTP-U layer is carried out, and the bag that compression is finished is transferred to GTP-U tunnel encapsulation and IP layer route transmission.Compressed package arrives ERS and delivers RLC ' through after separating the GTP-U tunnel encapsulation, after being transferred to UE through air interface then, PDCP ' the decompression machine of UE will be according to the Context decompress(ion) bag of setting up, decompress(ion) success back original packet data will be recovered, and handle on the upper strata (application layer) that will hand to PDCP '.

Describe the function of the lossless migration module in the RLC ' protocol entity below according to one embodiment of the present of invention, this function realization flow is as follows:

Referring to Fig. 4 and Fig. 6, in the two-layer node framework,, reused existing protocol to greatest extent in order to guarantee the smooth evolution of existing UTRAN framework.At the wireless interface oral-lateral, ERS except keeping original physical (L1), has added MAC layer, RLC ' layer owing to merged the function of most RNC in the past again.In wave point, because original PDCP layer disappears, the PDCP sequence number maintenance function of user data transmission that the PDCP layer is responsible for and support lossless migration moves down into RLC ' layer.And at network side, ERS has continued to use the Iu protocol stack of the interface of former RNC.IAGW has new PDCP ' layer and GTP-U tunnel related protocol.Wherein, new protocol layer PDCP ' function and interface are different from former PDCP, a main compression function and the encryption function be responsible for.At this, a compression function is finished by a compression module that moves from former PDCP entity.Two-layer node framework after the evolution because Radio interface protocols stack or user face protocol stack move down, so reduced transmission node, makes call setup time-delay and transmission delay shorten, and has improved data transmission performance.

In evolution architecture, when RLC ' is configured to submit with affirmation mode in proper order, RLC ' will support lossless migration, and the configuration of RLC ' is by the RRC agreement control of chain of command.In order to support lossless migration, the function that increases in original rlc layer is as follows:

1) RLC ' entity will be safeguarded the sequence number of RLC SDU.When having received a complete RLC SDU, receiving terminal RLC ' entity increases by 1 with the reception RLC sequence number of its maintenance, sends acknowledge message to transmitting terminal RLC ' entity simultaneously.When the RLC ' of transmitting terminal entity is received the affirmation message that opposite end RLC ' entity is sent, transmitting terminal RLC ' entity increases by 1 with the transmission RLC sequence number of its maintenance, deletes all protocol Data Units (PDU) corresponding with this SDU in the retransmission buffer simultaneously.

2) when carrying out the lossless migration flow process, but the RLC sequence number that UE and target ERS exchange are safeguarded separately has been used to confirm to send also has not been received and held the reception condition of confirming RLC SDU.After reorientation was finished, data sent from first not confirmed RLC SDU.

Below with reference to Fig. 7, the whole lossless migration flow process that the lossless migration module in the RLC ' protocol entity is finished is described.

In step 1, service edge wireless base station (SERS) needs to switch to object edge wireless base station (TERS) according to collected measurement data judgement UE.Because in evolution architecture, no Iur interface can't exchange data between SERS and TERS.SERS judgement Iu interface in direct-cut operation need carry out reorientation, sends reorientation to IAGW and requires (RELOCATION REQUIRED) message, trigger re-positioning (Relocation) process.

In step 2, after IAGW receives RELOCATION REQUIRED message, send re-positioning request (RELOCATION REQUEST) message to TERS, request TERS is the required resource of UE preassignment.

In step 3, after TERS receives RELOCATION REQUEST message, start relevant resource allocator, set up RRC connection, RAB carrying.Set up the RLC/MAC entity, set up new Radio Link, and start transmission and reception on the new Radio Link; Startup is simultaneously set up the GTP-U tunnel (GTP-U Tunnels for PS RABs) that is used for packet switching RAB and is come transmission bearer, sets up the user plane bearer between TERS and the IAGW.After all essential resources become the distribution of work, target ERS will send re-positioning request and reply (RELOCATION REQUEST ACKNOWEDGE) message to IAGW, confirm the resource allocation success.

In step 4, receive that after the RELOCATION REQUEST ACKNOWEDGE message, IAGW thinks that the goal systems resource allocation is ready, the reorientation flow process is proceeded in decision.IAGW will send reorientation order (RELOCATION COMMAND) message to SERS this moment, the execution of notice SERS trigger re-positioning.

In step 5, receive RELOCATION COMMAND message after, SERS stops the reorientation set-up procedure, and carries out following operation.Send to local RLC and to stop (STOP) order, require RLC stop with UE between data exchange; Transmit the data of local cache to TERS by the GTP-U passage; SERS obtains current expectation by primitive from RLC ' layer and accepts or RLC SDU frame number and GTP frame number to be sent, and sends forward direction SRNS context (FORWARD SRNSCONTEXT) message by IAGW to TERS, and the frame number that obtains is issued TERS.Simultaneously, SERS reads the Target RNC of RELOCATIONCOMMAND message and reshuffles (PHYSICAL CHANNELRECONFIGURATION) parameter to the physical channel in source RNC transparent vessel (the Target RNC To Source RNCTransparent Container) parameter, prepare direct-cut operation message PHYSICAL CHANNELRECONFIGURATION, be sent to UE by the Uu interface, trigger UE and insert Target cell.

In step 6, receive PHYSICAL CHANNEL RECONFIGURATION message after, UE will stop to exchange data with SERS, and the information that provides according to reconfiguration message inserts Target cell.After successfully inserting Target cell, UE will send physical channel and reshuffle and finish (PHYSICALCHANNEL RECONFIGURATION COMPLETE) message, and notice TERS handover success triggers the execution of TERS reorientation.UE obtains the frame number of the up RLC SDU of the current hope acceptance of TERS by reading PDCP sequence number information (the PDCP SN info) parameter in the PHYSICAL CHANNELRECONFIGURATION message.UE obtains behind this frame number by primitive, and the RLC ' entity that notice is local by RLC ' the entity frame number of the up RLC SDU that current hope sends of resetting, and is deleted confirmed RLC SDU.

In step 7, after TERS receives PHYSICAL CHANNEL RECONFIGURATIONCOMPLETE message, begin to carry out the function of SERS, and send reorientation detection (RELOCATION DETECT) message to IAGW, point out to detect SRNS Serving Radio Network Subsystem (SRNS, Serving Radio Network Subsystem) and carry out reorientation.After IAGW receives this message, user's face is switched to TERS by SERS.TERS obtains the frame number of the descending RLC SDU of the current hope acceptance of UE by reading the PDCP SN info parameter in the PHYSICAL CHANNELRECONFIGURATION COMPLETE message.After TERS obtains this frame number,,, and delete confirmed RLC SDU by RLC ' the entity frame number of the descending RLC SDU that current hope sends of resetting by the local RLC ' entity of primitive notice.After reorientation was finished, data sent from first not confirmed RLCSDU.

In step 8, TERS notifies IAGW by finishing (RELOCATIONCOMPLETE) message to IAGW transmission reorientation, and target ERS has finished the RELOCATION process.After IAGW receives RELOCATION COMPLETE message, carry out the Iu release command, the Iu interface that is discharged into SERS connects.

Obviously, those skilled in the art can carry out various changes and modification to the present invention and not break away from the spirit and scope of the present invention.Like this, if of the present invention these are revised and modification belongs within the scope of claim of the present invention and equivalent technologies thereof, then the present invention also is intended to comprise these changes and modification interior.

Claims

1, a kind of telecommunication system of two-layer node network architecture, described two-layer node comprises wireless base station, edge (ERS) and IP IAD (IAGW), wherein, wireless base station, edge (ERS) is that interior base station (NodeB) node of three-layer network framework telecommunication system and wireless network control (RNC) node form in conjunction with the back, it is characterized in that:

In each protocol entity on described two-layer node, a protocol entity comprises a compression module, and another protocol entity comprises the lossless migration module.

2, the system as claimed in claim 1 is characterized in that further comprising: the packet data polymerized agreement on the IP IAD (IAGW) (PDCP ') entity comprises a compression module.

3, system as claimed in claim 2 is characterized in that further comprising on the described IP IAD (IAGW):

GPRS Tunnel Protocol/User Datagram Protoco (UDP)/IP (GTP/UDP/IP) entity that links to each other with packet data polymerized agreement (PDCP ') entity;

The L2 physical layer protocol entity that links to each other with GPRS Tunnel Protocol/User Datagram Protoco (UDP)/IP (GTP/UDP/IP) entity;

The L1 physical layer protocol entity that links to each other with L2 physical layer protocol entity.

4, system as claimed in claim 1 or 2 is characterized in that further comprising: Radio Link on wireless base station, edge (ERS) control (RLC ') protocol entity comprises the lossless migration module.

5, system as claimed in claim 4, it is characterized in that Radio Link control (the RLC ') protocol entity on the wireless base station, described edge (ERS) further comprises all functions module in Radio Link control (RLC) entity on wireless network control (RNC) node in the three-layer network framework telecommunication system.

6, system as claimed in claim 4 is characterized in that further comprising on the wireless base station, described edge (ERS):

Medium access control (MAC) protocol entity that links to each other with Radio Link control (RLC ') protocol entity;

The L1 physical layer protocol entity that links to each other with medium access control (MAC) protocol entity.

7, system as claimed in claim 6 is characterized in that further comprising: described each protocol entity comprises, all functions module in the respective protocol entity on wireless network control (RNC) node in the three-layer network framework telecommunication system.

8, a kind of implementation method of telecommunication system two-layer node network architecture, described two-layer node comprises wireless base station, edge (ERS) and IP IAD (IAGW), wherein, wireless base station, edge (ERS) is that interior base station (NodeB) node of three-layer network framework telecommunication system and wireless network control (RNC) node form in conjunction with the back, and the method comprising the steps of:

A, on wireless base station, edge (ERS) node, form with three-layer network framework telecommunication system on wireless network control (RNC) node each protocol entity distinguish after corresponding protocols entity, remove packet data polymerized agreement (PDCP) entity wherein;

Compression module on B, interior wireless network control (RNC) node of three-layer network framework telecommunication system in packet data polymerized agreement (PDCP) entity moves on on the described two-layer node, form a protocol entity, simultaneously, lossless migration module in described packet data polymerized agreement (PDCP) entity moves on on the described two-layer node, forms another protocol entity.

9, method as claimed in claim 8 is characterized in that step B further comprises:

Move to IP IAD (IAGW) on the compression module in described packet data polymerized agreement (PDCP) entity, form packet data polymerized agreement on the described IP IAD (PDCP ') entity.

10, method as claimed in claim 8 or 9 is characterized in that step B further comprises:

Lossless migration module in described packet data polymerized agreement (PDCP) entity is displaced downwardly to the radio link control entity on the wireless base station, edge (ERS), and the Radio Link control after the formation increase function (RLC ') protocol entity.

11, a kind of method that compression module carries out the head compression, move on the compression module on wireless network control (RNC) node in packet data polymerized agreement (PDCP) entity after packet data polymerized agreement on the IP IAD (IAGW) (the PDCP ') entity, this method comprises:

A, wireless base station, edge (ERS) utilize the compressed configuration parameter of preserving in the memory of IP IAD (IAGW) to carry out the selection of header compression algorithm and the configuration and the negotiation of compressed parameter;

B, set up a compressed context between the compression module according to the feature of data flow separating on compression module on the IP IAD (IAGW) and subscriber equipment (UE) by selected compression algorithm;

C, described compression module and a described compression module of separating compress and decompression packet in succession according to a compressed context of being set up.

12, method as claimed in claim 11 is characterized in that steps A further comprises:

Wireless base station, edge (ERS) extracts a compressed configuration parameter and preserves from the instruction that IP IAD (IAGW) is sent, pass through land radio access web (UTRAN) then to subscriber equipment (UE) delivery header compression parameters;

After the compressed parameter that subscriber equipment (UE) analysis is received, carry out the configuration and the negotiation of parameter to separating a compression module.

13, method as claimed in claim 11 is characterized in that step B further comprises:

The data transmit-receive two ends utilize unpressed initial data packets to set up the context of data flow.

14, method as claimed in claim 11 is characterized in that step C further comprises:

Packet after the compression arrives wireless base station, edge (ERS) via the tunnel encapsulation and the IP route transmission of GPRS Tunnel Protocol user face (GTP-U);

Wireless base station, edge (ERS) is separated the packet of receiving and is handed to Radio Link control (RLC ') protocol entity after the tunnel encapsulation, is sent to subscriber equipment (UE) by air interface by described protocol entity;

Packet data polymerized agreement on the subscriber equipment (UE) (DPCP ') decompression module decompresses to the packet of receiving according to the context of being set up.

15, method as claimed in claim 11 is characterized in that the compression among the step C is that the above part of GPRS Tunnel Protocol user face (GTP-U) layer carried out.

16, a kind of lossless migration module is carried out the method for lossless migration, lossless migration module on wireless network control (RNC) node in packet data polymerized agreement (PDCP) entity is displaced downwardly to after Radio Link control on the wireless base station, edge (ERS) (the RLC ') protocol entity, and this method comprises:

A, during the RLC service data unit transmits, on the transmitting terminal with receiving terminal on the RLC sequence number of Radio Link control (RLC ') each self refresh self maintained of protocol entity;

B, when the lossless migration module is carried out context transfer from service edge wireless base station (SERS) to object edge wireless base station (TERS), service edge wireless base station (SERS) obtains RLC service data unit sequence number from the Radio Link of this locality control (RLC ') protocol entity, sends to object edge wireless base station (TERS) by IP IAD (IAGW);

The RLC sequence number that exchange is safeguarded separately between C, subscriber equipment (UE) and object edge wireless base station (TERS) confirms to send but also is not received the reception condition of the RLC service data unit of affirmation;

D, after reorientation is finished, data send from first not confirmed RLC service data unit.

17, method as claimed in claim 16 is characterized in that described steps A further comprises:

When receiving a complete service data unit, the progressively increase reception RLC sequence number of its maintenance of the Radio Link control on the receiving terminal (RLC ') protocol entity, the control of the Radio Link on transmitting terminal simultaneously (RLC ') protocol entity sends acknowledge message.

18, method as claimed in claim 17, it is characterized in that described steps A further comprises: when receiving acknowledge message, the progressively increase transmission RLC sequence number of its maintenance of Radio Link on transmitting terminal control (RLC ') protocol entity is deleted all protocol Data Units corresponding with this service data unit in the retransmission buffer simultaneously.

19, method as claimed in claim 16 is characterized in that described step B further comprises: service edge wireless base station (SERS) directly obtains RLC service data unit sequence number from the Radio Link of this locality control (RLC ') protocol entity by primitive.

20, method as claimed in claim 16, it is characterized in that described step C further comprises: exchanged separately after the RLC sequence number of safeguarding, subscriber equipment (UE) and object edge wireless base station (TERS) notify the frame number of local wireless control (RLC ') the current RLC service data unit that will send of protocol entity replacement separately.

21, method as claimed in claim 20 is characterized in that described step C further comprises: subscriber equipment (UE) and object edge wireless base station (TERS) are separately by primitive notice local wireless control (RLC ') protocol entity.