Field of the Invention

The present disclosure relates to method for initial NAS signalling in a wireless communication network. In particular, the invention relates to transport of initial NAS signalling messages on the interface between a relay node and another node in a mobile communication network.

Background

Wireless network technologies are widely deployed to provide various communication contents such as voice, video, packet data, messaging, broadcast, etc., which provide multiple-access systems capable of supporting multiple users by sharing the available system resources. In order to provide better qualities of service and wider communication ranges between wireless nodes, the concept of relay station has been introduced in network systems. The purpose of deploying relay station or Relay Node (RN) in network system is to extend the serving coverage of base station; hence, user equipment (UE) which is not within the communication coverage of base station can access the services provided by relay node as well via base station.

Wireless network architecture as defined by 3GPP introduces wireless relay node (RN) entity to extend the coverage of base station (evolved Node B or eNodeB or eNB). A long term evolution-advanced (LTE-A) system, as its name implies, is an evolution of the LTE system, considering relaying for cost-effective throughput enhancement and coverage extension. For example, a relay can be deployed at the cell edge where the eNB is unable to provide required radio quality/throughput for the UEs or at certain location where radio signals of the eNB cannot cover.

The Relay Node (RN) forms an independent physical cell. From a user equipment (UE) perspective, the RN is seen as a usual base station. The RN is connected via a wireless link to the base station. The relay node architecture deployment foresees that a RN emulates a base station for the UE, which means that the UE would see the RN as a usual base station. From the network side, the RN is seen as a usual UE by the base station. The base station or eNB, to which the RN is connected, is called Donor-eNB (Base station) hereinafter, referred to as Base station or eNB and operates as a usual base station. The deployment of RN in the 3GPP network architecture is described in 3GPP Technical Specification 36.806; "Relay architectures for E-UTRA (LTE-Advanced)".

In order for the user equipment to receive a service from the network, it needs to establish connectivity via base station, and initiating Non-Access Stratum (NAS) signalling messages with network nodes like Mobility Management Entity (MME) serving the UE. Consequential signalling messages are exchanged between network nodes to allocate bearer resources for UE and RN to service the UE request. The above bearer management procedure can be initiated by UE or the Evolved Packet Core (EPC in terms of 3GPP LTE) or simply the communication network..

Thus, whenever an initial UE bearer is created, the RN bearer create or modify procedures may be initiated by the RN. This increases the latency for the RN to modify/create a new bearer to service the UE. Thus, additional latency is introduced by the RN, when a bearer or multiple bearers are created for a UE during connection establishment, leading to delayed access service. Therefore, there is a need for a bearer management to optimize resources by effectively setting-up the bearers.

Summary of the invention

The summary represents the simplified condensed version of the claimed subject matter and it is not an extensive disclosure of the claimed subject matter. The summary neither identifies key or critical elements nor delineates the scope of the claimed subject matter. The summary presents the simplified form of the claimed subject matter and acts as a prelude to the detailed description that is given below.

The present invention and its embodiments are made to provide for a feasible solution for optimizing exchange of initial NAS signalling communication in a communication network.

An aspect of the invention provides for a method of managing initial NAS signalling in a communication network, by transporting "Union of Resource Request" (UR Request) signalling message from Evolved Packet Edge (EPE) entities to management entities of EPE via Base station and receiving "Independent Admission Response" (IA Response) signalling message for the transported UR Request from at least one of the said management entity of EPE by Base station, wherein the said management entity serves/manages all the entities in the EPE. EPE is a conglomeration of network nodes comprising of user equipment, relay node and all other network nodes that communicate over Evolved Packet Core (EPC) via Base station. Network nodes in the EPE may establish connectivity external to EPC like Internet or PSTN (Public Switch Telephone Network).

Another aspect relates to receiving "Independent Admission Response" (IA Response) signalling message for the transported UR Request from management entities of EPE by the Base station, wherein at least one of the said management entities are not serving/managing the same entities in the EPE. "Independent Admission Response" message comprises of granted bearer resources for UE and RN received independently by Base station from management entity or entities of EPE.

Another aspect relates to network nodes like RN, MMEJJE, MME_RN and systems facilitating the above method of managing bearers each comprising of at least a receiver, for receiving the said messages, processors for executing the functions, transmitter for transmitting messages, a memory for storing information and retaining instructions for executing functions associated with the above methods.

Other aspects, advantages, and salient features of the invention will become apparent to those skilled in the art from the following detailed description, which, taken in conjunction with the annexed drawings, discloses exemplary embodiments of the invention.

Description of the Drawings

The features, advantages and other aspects of the embodiments of the present invention will be obvious to any person skilled in the art to appreciate the invention when read with the following description taken in conjunction with the accompanying drawings.

Figure 1 is an illustration of existing bearer establishment procedure for user equipments (UE) and relay nodes (RN) as specified in 3GPP LTE (A) network architectures.

Figure 2 shows the network nodes conglomeration between two network entities in accordance with the principles of the invention.

Figure 3 is the flow chart of the functions performed by the relay node in accordance with the embodiments of the invention.

Figure 4 shows a detailed method of tagging (RN_TAG) in any one of the control plane protocol layers in accordance with the embodiments of the invention.

Figure 5 represents initial UE NAS signalling loop in accordance with various aspects of the invention.

The figures are not drawn to scale and are illustrated for simplicity and clarity to help understand the various embodiments of the present invention. Throughout the drawings it should be noted that like reference numbers are used to depict the same or similar elements, features and structures.

Detailed Description

The following descriptions with reference to the accompanying drawings are provided to assist in a comprehensive understanding of exemplary embodiments of the invention as defined by the claims and their equivalents. Accordingly, those of ordinary skill in the art will recognize that various changes and modifications of the embodiments described herein can be made without departing from the scope and spirit of the invention.

The terms and words used in the following description and claims are not limited to the bibliographical meanings, but, are merely used by the inventor to enable a clear and consistent understanding of the invention. The terms, component, module, system, and the like are intended to refer to an entity or entities within a communication network node comprising of; hardware, software, a combination of hardware and software. For e.g., a component may be, but not limited to being, a process running on a processor, a processor, an integrated circuit, or a computer. Both an application running on a computing device and the computing device can be a component. A component may be localized on one computer and/or distributed between two or more computers. The components may communicate by way of local and/or remote processes.

Those skilled in the art will understand that the principles of the present disclosure may be implemented in any suitably arranged systems. The terms used to describe various embodiments are exemplary. It should be understood that these are provided to merely aid the understanding of the description, and that their use and definitions in no way limit the scope of the invention.

Any term specifically reciting some of the present invention's characteristic, parameter, or value need not be achieved exactly, but that deviations or variations, including tolerances, measurement error, measurement accuracy limitations and other factors known to those of skilled in the art, may occur in amounts that do not preclude the effect the present invention was intended to provide.

The present invention and its embodiments are mainly described in relation to 3GPP specifications and standards (LTE-Advanced) for applicability of certain exemplary embodiments. The terminology used is therefore related thereto. Such terminology is used in the context of describing the embodiments of the invention and it does not limit the invention in any way. Any other network architecture or system deployment, etc., may also be utilized as long as it is compliant with the features described herein.

In particular, embodiments of the present invention may be applicable in any relay-enhanced (cellular) system with a need for signalling optimization. Embodiments of the present invention may be applicable for/in any kind of modern and future communication network including any mobile/wireless communication networks/systems.

Example embodiments to be described below are not intended to limit the present invention to any specific example, embodiment, environment, applications, or particular implementations described in these example embodiments. It should be appreciated that, in the following example embodiments and the attached drawings are illustrated for the ease of understanding, but not to limit the actual scale.

The following paragraphs will describe various embodiments of the invention. For exemplary purposes only, most of the embodiments are outlined according to the LTE-Advanced mobile communication system with the solution to the problem discussed in the background. It should be noted that the invention may be advantageously used in connection with the communication system described above, but the invention is not limited to its use in this particular exemplary communication network. The explanations given below are intended to better understand specific exemplary embodiments described herein and should not be understood as limiting the invention to the specific implementations of processes and functions in a mobile communication network. The improvements/solutions proposed herein may be readily applied in architectures/systems having relevance to relay architectures. Some embodiments of the invention may also make use of standard and improved procedures of these architectures/systems.

The techniques described herein may be used for various wireless communication networks such as CDMA networks, CDMA implementing radio technology such as UTRA, TDMA networks, TDMA implementing radio technology such as GSM, FDMA networks, OFDMA networks, OFDDA implementing radio technology such as Evolved URTA (E-UTRA), SC-FDMA networks.

User equipment (UE) used in the following description denotes various terminologies used like an access terminal (AT), wireless communication device, terminal, wireless handset, computer or wireless module, wireless module for use with a computer, personal digital assistant (PDA), tablet computer or device.

In the overall architecture of a network with a relay node (RN), a relay node has a Base station and a terminal side called as user equipment (UE). Towards UE the RN behaves as a conventional eNB using the access link (Uu interface) and the UE is not aware of whether it is communicating with a relay node or a base station. Relay nodes are therefore transparent for the UE. Towards base stations relay nodes initially operate as a UE using the radio interface to connect to the base station. Once connection is established and the relay node is configured, the relay uses a subset of the UE functionality for communication on the backhaul link (Un interface). In relay architecture eNB acts as a proxy between the core network and the relay node.

The UEs are connected to the RN by means of a Uu interface and the RN to the eNB by means of Un interface. When the network e.g., MME has no valid location or routing information for the UE, the UE cannot be reached. This is more likely when the UE is in a state of switched off, or out of coverage area. 3GPP defines this state as a de-registered state and this could also happen when the UE is in non-3GPP access. When the UE is attached to the network e.g., MME, it can receive Core Network services. This state is defined by 3GPP as registered state. In this registered state the UE can be in two different connection management states like RRCJDLE state and RRC_CONNECTED state. When no data is being transmitted and the radio resources are released, the UE has a valid IP configuration. In such idle state there is no Non-Access Stratum (NAS) signalling connection between the UE and the network, e.g., MME. Also during the idle state there is no S1 connection between the eNB and the Serving Gateway. In the RRC_CONNECTED state, there is an active connection between the UE and eNB, which implies a communication context being stored within the eNB for this UE. Both sides can exchange user data and or signalling messages over logical channels.

From the wireless network perspective, protocol structure for the User and Control planes correspond to user data transmission and signalling transmission. Control plane corresponds to the information flows actually considered as signalling by E-UTRAN and Core Network. This includes all the RRC (Radio Resource Control) E-UTRAN signalling (supporting functions such as Radio Bearer management, radio mobility, user paging) and NAS (Non Access Stratum) signalling. On the radio interface, the Control plane uses the Control plane protocol stack namely PDCP (Packet Data Convergence Protocol), RLC (Radio Link Control), MAC (Medium Access Control) and PHY (Physical) stack to transport both RRC and Core Network NAS signalling. The above protocol stack layers support the same functions for both the User and Control Planes. When a Non-Access Stratum (NAS) signalling connection needs to be established between UE and the MME routed via relay node, the UE and the MME shall enter the connected state. It should be noted that an eNB can have connections to one or more MMEs and S-GW node.

Figure 1 shows the initial NAS signalling message for bearer initiation procedure existing in 3GPP LTE specification. UE 20 sends an initial NAS message or service request to the MMEJJE 101a, which is routed through RN 10 and eNB 30. When a NAS layer in the UE has to send an initial NAS message denoted as 'UE NAS Msg' in fig 1, the UE first initiates the establishment of the Radio Resource Control (RRC) connection over the Uu interface. The RRC procedures are elaborated in 3GPP specification TS 36.331 available at www.3gpp.org. In parallel to the establishment of the RRC connection over the Uu interface, the RN initiates the establishment of the RRC connection over the Un interface. The RRC connection establishment procedure over the Uu and Un interfaces are as per the 3GPP specification.

The NAS message is directed to MME (UE) 101a and the RN 10 is transparent. The MMEJJE 101a understands the message and forwards it to the SGW/PGWJJE 102a for checking the UE subscription data. Then the SGW/PGWJJE 102a in conjunction with PCRF (not shown) authorizes MMEJJE 101a to create a dedicated bearer and sends the message over S11 interface (Interface between S/PGW and MME). On receiving the response, MMEJJE 101a sends bearer setup request to the UE 20 as an S1-AP message routed through RN 10. RN 10 understands this S1-AP message and initiates RRC configuration between UE 20 and RN 10. UE 20 sends RRC Reconfiguration Complete to RN 10. Then RN 10 sends initial context setup response to MMEJJE 101a. A bearer setup response may be sent by UE 20 to MMEJJE 101a routed via RN 10 and eNB 30 at NAS level. On receiving the response from UE 20, MMEJJE 101a establishes the bearers and sends the response to SGW/PGWJJE 102a. This process establishes radio bearers to enable data flow from the SGW/PGWJJE 102a to the UE 20. After completion of this procedure, the RN 10 may send a NAS message seeking bearer-resource request to MME_RN 101b via eNB 30. MME_RN 101b understands the message and provisions bearer resource allocation to RN 10. Upon receiving bearer resource allocation, RN 10 bearer establishment is completed. Radio resources for the relay node 10 are allocated so as to serve the already established UE's bearer requirements. Thus in the above instances whenever an initial UE 20 bearer is created, the RN bearer, modify or create may be initiated subsequently by the RN 10. Thus additional messages are exchanged separately for the UE 20 and for the RN 10 to modify/create a new bearer. This either wastes or underutilizes the backhaul bandwidth. Further, there is delay in traffic flow.

Figure 2 shows the network nodes conglomeration between two network entities in accordance with the principles of the invention. Network entity 625 is called as Evolved Packet Edge (EPE) comprising of plurality of network nodes like UE, RN and all other nodes that communicate with Evolved Packet Core Network entity 675 via Base station 30. Network nodes in the EPE 625 may establish connectivity external to EPC like Internet 106 or PSTN (Public Switch Telephone Network) 107. EPC entity 675 comprises of network nodes like Mobility Management Entity (MME), Serving gate way/Packet gate way (S/PGW), Policy of Charging Rules Function etc. These nodes essentially manage the entities in the EPE. For e.g., a UE bearer resource request is processed and allowed only by the MME serving the UE. Without any loss of generality, it is appropriate to indicate MME serving the UEs as MME_UE and MME serving the RNs as MME_RN. It can happen that MME serving the UEs and RNs respectively can be one single MME.

As part of bearer management signalling as envisaged, a communication from EPE 625 comprising of initial bearer resource request of UE and the consequential bearer resource request of RN is transported via Base station 30 to EPC as a single signalling message over uplink channel 651 hereinafter referred to as "Union of Resource Request" (UR Request) message. The response message comprising of bearer resource response from either one of the managing entity or managing entities of EPC 675 are transported as a single signalling message to Base station 30 over the downlink channel 652 hereinafter referred to as "Independent Admission Response" (IA Response). This manages bearer setup signalling loop, with a single transportation of 'UR Request' signalling message and receiving "Independent Admission Response" signalling message over uplink and downlink channels respectively.

When the UE 20 is in the de-registered state, UE NAS signalling message that initiates a transition from the de-registered state to the connected state are 'Attach Request', Tracking Area Update Request', 'Service Request' or 'Detach Request'. The UE NAS message received as part of RRC Connection Setup Complete is initial UE NAS message which is not an encrypted message. If the UE has valid security parameters stored, then the initial UE NAS message shall be integrity protected. Otherwise, the initial UE NAS message will not be integrity protected. The request of UE 20 for allocating bearer resources is referred to as 'service request' message.

Figure 3 is the flow chart representing the functionality 800 performed by the relay node 10, in accordance with the embodiments of the invention. As described above, the embodied functionality of RN 10 begins at 801 wherein it receives initial UE NAS Message and at 802, the initial UE NAS message is checked by the RN to identify whether it is a 'service request' message. If the received message is a 'service request' message then at 803 the RN checks whether the requested bearer resources of UE are not within the available resources of the RN to cater to the said UE service request. If the UE service request is not within its available resources, then at 804, RN adds its identity with the received initial UE NAS message, denoted as 'Initial UE NAS msg+RN_ID' referred to as 'tagged message' (RN_TAG). Relay node identity or RNJD is a unique identifier that helps identifying the MME serving the said RN. Relay node identity comprises of MME Group ID, MME code of MME_RN. At 805, the RN forwards the said tagged message to the managing entity of EPC 675 via Base station 30. The tagged message is available at the EPC as 'UR Request' message, which is essentially a service request message for the RN and the UE. At 802, if the RN finds that the received message is not a 'service request' message, or finds at 803, that the UE service request is within its available resources so as to cater to the UE bearer requirements then the RN handles the received initial UE NAS message as other control plane signalling message at the above stages of 806 and 807 respectively. "Union of Resource Request" message received by the Base station are forwarded to the respective management entities of EPE.

Figure 4 depicts protocol layers through which insertion of RN_TAG (comprising of RNJD and type prefix for the said RNJD) by the RN 10 preferably at NAS layer or at any one of the other control plane protocol layers like, S1-AP, SCTP, PDCP, RLC, MAC, PHY, is accomplished in accordance with the embodiments of the invention. For the sake of illustration the flow of uplink signalling data in case of two radio bearers is shown with possible RN_TAG insertion points, at any one of the protocol layers. For the sake of brevity, the control plane protocol layer 410 above PDCP layer 401 is shown as an integrated layer comprising of NAS, S1-AP, and SCTP (Stream Control Transmission Protocol).

Figure 5 represents initial bearer setup signalling loop, with a single transportation of 'UR Request' signalling message by EPE entities and receiving "Independent Admission Response" signalling message by Base station in accordance with the embodiments of the present invention. Initial UE NAS messages are generated by UE (Step 1). When the RN 10 receives the initial UE NAS Message (Step 2), from UE 20, the RN 10 adds (Step 3) the received 'initial UE NAS Message' with the identity of the said relay node 'RNJD' after verifying it to be UE service request message as explained above in figure 3, to be sent to the MMEJJE 101a via Donor eNB 30. The denotation 'Initial UE NAS Msg+RNJD' means that it is a tagged message essentially consisting of service request message of UE and RN 10 Identity (Step 4). The above denotation is specifically defined for the purpose of this invention as a tagged message denoted as RN_TAG. The RN_TAG is then transmitted from the RN 10 to the MMEJJE 101a via Base station 30 over Un interface as a control plane signalling message. When this RN_TAG arrives at Base station 30, Base station 30 understands the message to be a 'RNJTAG' message except when tagged at NAS layer and then forwards it to MMEJJE 101a; the MMEJJE 101a, understands the message (Step 5) and the MMEJJE 101a processes UE 20 service request and grants utmost UE service request. If MMEJJE 101a grants the request, an 'S1-AP message for UE' is generated and forwarded to Base station 30. Base station 30 receives the 'S1-AP message for UE' (Step 6) and forwards to RN. Simultaneously MMEJJE generates a relay node resource request (RR Request) message to be sent to MME_RN 101b. If the MMEJJE 101a does not grant UE 20 service request, then MMEJJE 101a generates 'UE NAS message for bearer resource reject' and forwards it for UE 20 via Base station 30 (Step 11).

The 'RR Request' message generated by the MMEJJE 101a for MME_RN 101b is a service request on behalf of RN 10. The message essentially is an establishment of RN bearer to serve UE bearer QoS requirements (Step 7).

Once RN 10 bearer request is granted, MME_RN 101b generates 'S1-AP message for RN' and then forwards it to Base station 30 (Step 9). If the MME_RN 101b does not grant 'RR Request' made by MMEJJE 101a, then MME_RN 101b generates 'RN NAS message for bearer resource reject', and then forwards it to RN 10(Step 8). Base station 30 processes the received 'S1-AP message' for RN (Step 10) and performs RRC configuration (Step 12) for the downstream relay node and forwards 'S1-AP messages for the remaining EPE entites. Performing RRC configuration for the downstream relay node by Base station and performing RRC configuration by relay node to the UE (Step 13) are similar to those functions elaborated in 3GPP specification.

"Independent Admission Response" (IA Response) that are available to Base station 30 comprises of bearer resource allocation message pertaining to the respective EPE entities. For e.g., if MMEJJE grants UE service request x to UE (Y), it generates an 'S1-AP message for UE' and forwards to Base station which may be in the form of Y(x). Similarly RN NAS messages seeking bearer allocation for the relay node 'P' is forwarded to the respective MME_RN. MME_RN may grant the same resources 'x' to the relay node 'P'. In such cases MME_RN serving the RN 'P' may generate an 'S1-AP message for RN' which may be in the form of x(P) and forward it to Base station. The "Independent Admission Response" from MMEJJE i.e., Y(x), is understood by the Base station as a message comprising of allocated bearer resources corresponding to the value of 'x' to UE. "Independent Admission Response" from MME_RN i.e., x(P) is understood by the Base station as a message comprising of allocated bearer resources corresponding to the value of 'x' for the relay node 'P. In the above given example, in case MME_RN grants bearer resources for the relay node 'P' corresponding to the value less than the granted value of UE i.e., 'x-a', then the 'S1-AP message for RN' would be in the form b(P), (where x-a=b). When this "Independent Admission Response" message is received by Base station, it understands as a message comprising of allocated bearer resources corresponding to the value of 'b' for the relay node 'P'. It is also possible that MMERN managing the relay node 'P' denies granting any of the bearer resources for the relay node 'P', then the "Independent Admission Response" message that is generated by MME_RN would be 'P()When this "Independent Admission Response" is received by the Base station, it understands as a message comprising of 'RN NAS message for bearer resource reject'. It should be noted that in case of a single management entity (like, MME) serving all the entities in the EPE, the above functions of independently allocating or denying service requests of UE and RN are performed by that management entity alone as illustrated above.

Another embodiment of the invention relates to the implementation of the above described various embodiments using hardware and software. It is recognized that the various embodiments of the invention may be implemented or performed using computing devices (processors). A computing device or processor may for e.g., be general purpose processors, digital signal processors (DSP), application specific integrated circuits (ASIC), field programmable gate arrays (FPGA) or other programmable logic devices, etc. The various embodiments of the invention may also be performed or embodied by a combination of these devices

Further, the various embodiments of the invention may also be implemented by means of software modules, which are executed by a processor or directly in hardware. Also a combination of software modules and a hardware implementation may be possible. The software modules may be stored on any kind of computer readable storage media, for example RAM, EPROM, EEPROM, flash memory, registers, hard disks, CD-ROM, DVD, etc.

It is to be noted that respective functional blocks or elements according to above-described aspects can be implemented by any known means, either in hardware and/or software, respectively, if it is only adapted to perform the described functions of the respective parts. The mentioned method, steps can be realized in individual functional blocks or by individual devices, or one or more of the method, steps can be realized in a single functional block or by a single device.

The present invention also covers any conceivable combination of method steps and operations described above, and any conceivable combination of nodes, apparatuses, modules or elements described above, as long as the above-described concepts of methodology and structural arrangement are applicable.

It should be further noted that the individual features of the different embodiments of the invention may individually or in arbitrary combination be subject matter to another invention.

It would be appreciated by a person skilled in the art that numerous variations and/or modifications may be made to the present invention as shown in the specific embodiments without departing from the spirit or scope of the invention as broadly described. The present embodiments are, therefore, to be considered in all respects to be illustrative and not restrictive.

We Claim:

1. A method for initial NAS signalling in a communication network, the method comprising of;
Forming "Union of Resource (UR) Request" message for the initial UE NAS message in the Evolved Packet Edge (EPE), wherein EPE includes at least a user equipment (UE) and one relay node (RN);

Transporting the "UR Request" message from the EPE via Base station to managing entity of user equipment (UE) within EPC, wherein 'managing entity of UE' are network nodes that manage or administer UE, like mobility management entity serving the user equipment (MME_UE), serving gate way, packet gate way, PCRF, HSS or combination thereof; and

Receiving "Independent Admission (IA) Response" by the Base station for the transported "UR Request" from one of the said management entity, wherein the said management entity is the mobility management entity that serves/manages all the entities in the EPE.

2. A method for initial NAS signalling in a communication network, the method comprising of;

Forming "Union of Resource (UR) Request" message for the initial UE NAS message in the Evolved Packet Edge (EPE), wherein EPE includes at least a user equipment (UE) and one relay node (RN);

Transporting the "UR Request" message from the EPE via Base station to managing entity of user equipment (UE) within EPC, wherein 'managing entity of UE' are network nodes that manage or administer UE like mobility management entity serving the user equipment (MMEJJE), serving gate way, packet gate way, PCRF, HSS or combination thereof; and

Receiving "Independent Admission (IA) Response" by the Base station for the transported UR Request, from one of the said management entities within EPC wherein at least one of the said management entities is the mobility management entity not serving/managing the same entities in the EPE.

3. The method of claim 1, wherein forming "UR Request" for the initial UE NAS message comprises of;

Identifying the received initial UE NAS message by the relay node to be a service request wherein identifying may include, identifying whether the received message is integrity protected or not; identifying whether the received initial UE NAS message is a service request or not; checking the available bearer resources of the said relay node to cater to the needs of initial UE service request;

Treating the received initial UE NAS message as other control plane signalling message if the initial UE NAS message is not a service request, if the available bearer resources of the relay node caters to the needs of the initial UE service request;

Tagging the initial UE NAS message received by the relay node if the received initial UE NAS message is an UE service request, wherein tagging includes adding relay node identity (RNJD) with the said received initial UE NAS message, at least in any one of the control plane protocol layers like PDCP, RLC, MAC, PHY, S1-AP, SCTP, preferably over NAS; and

Forwarding the said 'tagged message' to the MMEJJE via Base station.

4. The method of claim 2, wherein forming "UR Request" for the initial UE NAS message comprises of;

Identifying the received initial UE NAS message by the relay node to be a service request wherein identifying may include,

identifying whether the received message is integrity protected or not; identifying whether the received initial UE NAS message is a service request or not; checking the available bearer resources of the said relay node to cater to the needs of initial UE service request;

Treating the received initial UE NAS message as other control plane signaling message; if the initial UE NAS message is not a service request, if the available bearer resources of the relay node caters to the needs of the initial UE service request;

Tagging the initial UE NAS message received by the relay node if the received initial UE NAS message is an UE service request, wherein tagging includes adding relay node identity (RNJD) with the said received initial UE NAS message, at least in any one of the control plane protocol layers like PDCP, RLC, MAC, PHY, S1-AP, SCTP, preferably over NAS; and

Forwarding the said 'tagged message' to the MMEJJE via Base station.

5. The method of claim 1 further comprising of;

Receiving the tagged message by MMEJJE;

Granting utmost "UR Request" by the said MMEJJE, wherein granting includes generating 'S1-AP message for UE' and 'S1-AP message for RN' for the relay node identified by the said relay node identity (RNJD) if accepted, and generating 'UE NAS message for bearer resource reject' and generating 'RN NAS message for bearer resource reject' if rejecting, for the said received tagged message'; and

Forwarding to Base station, one among the messages comprising of: 'UE NAS message for bearer resource reject', 'S1-AP message for UE' and 'S1-AP message for RN' for the relay node identified by the said relay node identity (RNJD);

6. The method of Claim 2 further comprising of;

Receiving the tagged message by MMEJJE;

Granting utmost "UR Request" by the said MMEJJE, wherein granting includes understanding, rejecting, accepting, and generating 'UE NAS message for bearer resource reject' if rejecting, generating 'S1-AP message for UE' and generating relay node resource request (RR request) message for MME_RN identified by relay node identity (RNJD) for the granted UE resources by MMEJJE, if accepting, for the said received tagged message;

Forwarding to Base station, one among the generated messages comprising of: 'S1-AP message for UE', 'UE NAS message for bearer resource reject';

Forwarding the generated 'RR Request' message to MME_RN identified by relay node identity (RNJD);

Receiving 'RR Request' message by MME_RN from MMEJJE;

Granting utmost "RR Request" by the said MME_RN, wherein granting includes, rejecting, accepting, and generating 'RN NAS message for bearer resource reject' if rejecting, generating 'S1-AP message for RN' for the relay node identified by the said relay node identity (RNJD), if accepting, for the said received "RR Request" message; and

Forwarding to Base station, one among the generated messages comprising of: 'RN NAS message for bearer resource reject' 'S1-AP message for RN', for the relay node identified by the said relay node identity (RNJD);

7. An initial NAS signalling system for relay node in a communication network comprising of;

A receiver for receiving at least a UE NAS Message, RN NAS message, 'S1-AP message for UE' and 'S1-AP message for RN';

A processor for identifying the received initial UE NAS message to be a service request wherein identifying may include identifying whether the received message is integrity protected or not; identifying whether the received initial UE NAS message is a service request or not; checking the available bearer resources of the said relay node to cater to the needs of initial UE service request;

A processor for treating the received initial UE NAS message as other control plane signalling message; if the initial UE NAS message is not a service request, if the available bearer resources of the relay node caters to the needs of the initial UE service request;

A processor for tagging if the received initial UE NAS message is an UE bearer resource request wherein, tagging includes adding relay node identity (RNJD) with the said received initial UE NAS message, at least in any one of the control plane protocol layers like PDCP, RLC, MAC, PHY, S1-AP, SCTP, preferably over NAS;

A processor for understanding the received 'S1-AP Message for downstream node', 'RN NAS message' and 'UE NAS message' from Base station and performing RRC configuration, if the received message is an 'S1-AP Message';

A transmitter for transmitting the tagged message to Base station; and transmitting, 'NAS message', RRC radio bearer configuration message, 'S1-AP message'; and

A memory for retaining instructions for executing functions associated with the receiver, processor/processors, and transmitter and as well as measured or computed data that may be generated during executing such functions.

8. An initial NAS signalling system for MME_UE in a communication network comprising of;
A receiver for receiving at least a tagged message from Base station, comprising initial UE NAS Message and relay node identities (RNJDs);

A processor for granting utmost UE resource request and generating 'S1-AP message for UE', 'RR Request' message for MME_RN, if UE resource request has been granted, and for generating a 'UE NAS message for bearer resource reject' if the UE resource request has not been granted;

A Transmitter for transmitting 'RR Request' messages to MME_RN, one among 'UE NAS message for bearer resource reject', 'S1-AP message for UE' to Base station; and

A memory for storing and retaining instructions for executing functions associated with the receiver, processors, and transmitter and as well as measured or computed data that may be generated during executing such functions.

9. An initial NAS signalling system for MME_RN in a communication network comprising of;

A receiver for receiving at least a 'RR Request' message from MME_UE comprising RN service request for relay node;

A processor for granting 'RR Request' and generating 'S1-AP message for RN', for the relay node identified by the relay node identity (RNJD), if the relay node resource request has been granted, and for generating a 'RN NAS message for bearer resource reject' if the relay node resource request has not been granted;

A Transmitter for transmitting to Base station, one among the generated messages comprising of: 'RN NAS message of bearer resource reject' 'S1-AP message for RN', for the relay node identified by the relay node identity (RNJD); and

A memory for retaining instructions for executing functions associated with the receiver, processors, and transmitter and as well as measured or computed data that may be generated during executing such functions.