WO2014187601A1

WO2014187601A1 - Device to device communication

Info

Publication number: WO2014187601A1
Application number: PCT/EP2014/056540
Authority: WO
Inventors: Anand MURALIDHAR; Jayashree SUBRAMANIAN; Satish Kanugovi
Original assignee: Alcatel Lucent
Priority date: 2013-05-20
Filing date: 2014-04-01
Publication date: 2014-11-27

Abstract

Method(s) and system(s) for device to device discovery are disclosed. The method comprises, receiving a service request from a service availing device (102) seeking to avail at least one service, wherein the service request indicates the at least one service. The method further comprises providing a link message to the service availing device (102) and at least one service offering device (102) associated with the at least one service, based on the service request, for initiating device discovery to establish a D2D link for availing the at least one service.

Description

DEVICE TO DEVICE COMMUNICATION

FIELD OF INVENTION

[0001] The present subject matter relates to device to device (D2D) communication and, particularly, but not exclusively, to D2D discovery.

BACKGROUND [0002] Over the years, there has been an exponential increase in the number of users availing communication services offered by a service provider over communication networks. The users typically avail such services using user devices, such as cellular phones, smart phones, personal digital assistants (PDAs), portable computers, and desktop computers. However, with the increase in the number of users, the network traffic exchanged over the communication network has also increased significantly. With advancement in technology, alternate communication techniques, such as device-to-device (D2D) communication have been developed for reducing network traffic and providing efficient mode of data transfer without incurring network usage charges. The D2D communication concerns wireless communications directly between two user devices. For example, WiFi Direct is a technique by which devices can directly communicate over WiFi channels without any intermediary network elements.

SUMMARY

[0003] This summary is provided to introduce concepts related to device to device (D2D) communication. This summary is not intended to identify essential features of the claimed subject matter nor is it intended for use in determining or limiting the scope of the claimed subject matter.

[0004] In one implementation, a method for device to device discovery is described. The method includes receiving a service request from a service availing device seeking to avail at least one service, wherein the service request indicates the at least one service. The method further comprises providing a link message to the service availing device and at least one service offering device associated with the at least one service, based on the service request, for initiating device discovery to establish a D2D link for availing the at least one service. Further, a registration request from each of the one or more service offering devices is received, wherein the registration request includes at least one of an identity credentials, service name, and service information, and wherein the service information includes at least one of a name, a type, a quality of service, and a service discovery range. The method further comprises registering each of the one or more service offering devices based on the corresponding identity credentials included in the registration request. Further, a service list including service details of one or more services offered by the one ore more service offering devices registered with the base station is broadcasted, wherein each of the one or more services is provided by one or more service offering devices associated with the service.

[0005] In another implementation, a method for establishing a device to device link is described. The method comprises providing a service request for availing at least one service to a base station, wherein the service request indicates the at least one service. The method further comprises receiving a link message for initiating device discovery with at least one service offering device associated with the at least one service based on the service request. Further, a service list including service details of one or more services is obtained, wherein each of the one or more services is provided by one or more service offering devices associated with the service. The method further comprises, sending a registration request for registering with the base station, wherein the registration request includes at least one of an identity credentials, service name, and service information, and wherein the service information includes at least one of a name, a type, a quality of service, and a service discovery range.

[0006] In another implementation, a base station for facilitating device to device discovery is described. The base station includes a processor and a broadcast module coupled to the processor. In one implementation, the broadcast module receives a service request from a service availing device seeking to avail at least one service, wherein the service request indicates the at least one service. The broadcast module further provides a link message to the service availing device and at least one service offering device associated with the at least one service, based on the service request, for initiating device discovery to establish a D2D link for availing the at least one service. The broadcast module may further generate a service list based on a registration request, wherein the service list includes service details of one or more services offered by one or more service offering devices registered with the base station, wherein each of the one or more services is provided by one or more service offering devices associated with the service. Thereafter, the broadcast module broadcasts the service list. The base station may further include a registration module coupled to the processor. The registration module receives the registration request from the service availing device and each of the one or more service offering devices, wherein the registration request includes at least one of an identity credentials, a service name, and a service information. Further, the registration module registers the service availing device and the one or more service offering device based on the identity credentials.

[0007] In accordance with another implementation of the present subject matter, a computer-readable medium having embodied thereon a computer program for executing a method of D2D discovery is described. The method includes receiving a service request from a service availing device seeking to avail at least one service, wherein the service request indicates the at least one service. The method further comprises providing a link message to the service availing device and at least one service offering device associated with the at least one service for initiating device discovery based on the service request.

BRIEF DESCRIPTION OF THE FIGURES

[0008] The detailed description is described with reference to the accompanying figures.

In the figures, the left-most digit(s) of a reference number identifies the figure in which the reference number first appears. The same numbers are used throughout the figures to reference like features and components. Some embodiments of system and/or methods in accordance with embodiments of the present subject matter are now described, by way of example only, and with reference to the accompanying figures, in which:

[0009] Figure 1 illustrates an exemplary network environment implementation for device to device (D2D) communication, according to an embodiment of the present subject matter; [0010] Figure 2 illustrates a method for device to device (D2D) discovery, according to an embodiment of the present subject matter; and

[0011] Figure 3 illustrates a method for establishing a D2D link, in accordance with an embodiment of the present subject matter.

DESCRIPTION OF EMBODIMENTS [0012] With advancement in technology, communication techniques, such as device- device (D2D) communication have been developed as an alternate means of communication amongst user devices for reducing network traffic over a conventional wireless communication network. The D2D communication typically involves communication between two user devices, in proximity to each other, without the use of network elements, such as a base station. For instance, Wifi Direct and Bluetooth techniques enable two or more user devices, in proximity to each other, to communicate with each other over a D2D link established between them.

[0013] Establishment of the D2D link is typically preceded with a D2D discovery mechanism used for discovering a user device for establishing the D2D link. In a conventional D2D discovery mechanism, a user device continually scans the surrounding environment for determining presence of one or more user devices offering several services in the surrounding environment. The user device then ascertains the service being offered by each of the user devices and subsequently selects a second user device for seeking the services offered by the second user device. However, continuous scanning of the surrounding environment by the user device may lead to high consumption of battery power, thereby resulting in limited operational time and low battery backup for the user device. Further, the scanning capabilities of the user device may be limited due to the limited transmission range of the user device, thereby limiting the operational capabilities of the user device. In a conventional method for establishing a D2D link, a first user device may continually transmit beacon signals in order to discover other devices in radio frequency (RF) proximity of the first user device. For example, in a mall or a stadium, a group of friends seeking to establish the D2D link amongst themselves may continually transmit beacon signals over the wireless network. In such a case, continuous transmission of such beacon signals may thus lead to increase in the number of channel resources being utilized resulting in network congestion. [0014] The present subject matter discloses systems and methods for D2D discovery.

According to an embodiment of the present subject matter, one or more service offering devices may offer services, such as music broadcast, gaming, printing, content sharing, and video broadcasting in an environment supporting D2D communication between user devices. In order to avail any of the aforementioned services using the D2D communication, a user may initially select the service through a corresponding service availing device. Upon selection of the service, a base station associated with a network operator of the service availing device may provide the details of service offering devices offering the selected services to the service availing device. The service availing device may thus establish a D2D link based on the details. The present subject matter thus facilitates the D2D discovery. In one implementation, one or more user devices may initially register with the base station associated with their respective network operators in order to avail or provide the services.

[0015] In said embodiment, the base station may initially broadcast a service list having details of one or more services offered by the one or more service offering devices such that each of the one or more services is provided by one or more user devices associated with the service. In one implementation, the service list may include services which a user device may avail in its RF proximity. In another implementation, the service list may also include the services provided by service offering devices that are not in RF proximity of the service availing devices but are present in the same geographical region as the service availing devices. The user of the service availing device in such a case may move closer to the service offering devices to come in their RF proximity for availing the service.

[0016] Upon receiving the broadcast, a user of a service availing device may seek to avail a service from amongst the one or more services enlisted in the service list. For example, the user upon receiving the service list including services, such as gaming, music broadcast, and content sharing, may wish to listen to music and may subsequently select the music broadcast service from the service list.

[0017] Upon receiving a user input from the user, the service availing device may select the service which the user seeks to avail. Subsequently, the service availing device may transmit a service request indicating the selected service to the base station. Upon receiving the service request, the base station may determine a service offering device from the one or more service offering devices providing the service. The base station may subsequently provide a link message to the service availing device and the service offering device for initiating a device discovery mechanism. In one implementation, the link message may include, identity credentials, such as an internet protocol (IP) address and a machine address (MAC-id). In another implementation, the base station may transmit the link message to the service availing device and more than one service offering devices providing the service.

[0018] Thereafter, the service availing device may initiate a device discovery mechanism based on the link message and may subsequently establish a D2D link with the service offering device for availing the service. In another implementation, the service offering device may initiate the device discovery based on the link message and establish the D2D link with the service availing device. The service offering device may subsequently offer the service to the service availing device over the D2D link.

[0019] In another embodiment, before receiving the service list, a service availing device may send a service request to the base station for availing a service which the user may seek to avail. Upon receiving the service request, the base station may ascertain the availability of the service based on an internal service record. In a case where the service is available, the base station may transmit a link message to the service availing device and at least one service offering device providing the service. The service availing device and the at least one service offering device may subsequently establish a D2D link in a manner as described above.

[0020] As will be understood from the foregoing description, the services available in a geographical region or a nearby geographical region of the user device is broadcasted by the base station, in the form of a service list, the need for continually transmitting the beacon signals for discovering other user device offering services is averted. Thus, the D2D discovery in accordance with the present subject matter results in an efficient utilization of spectrum and channel resources. Further, establishment of the D2D link based on the link message results in lower battery consumption as the user device is provided with a smaller set of user devices offering the desired service. Thus, the need for scanning the surrounding environment and subsequently ascertaining the service provided by each of the user device present in the proximity is eliminated leading to less battery power consumption. Further, processing of a limited number of user devices for establishing the D2D link helps in reducing the time involved in the D2D discovery mechanism. Moreover, the presence of a centralized network entity, such as the base station helps in monitoring and providing the services across an increased range of discovery as the base station broadcasts the list of available services to all the user devices. The user device may thus be provided with a range of choices of services and service offering devices as compared to the situation where, the user device, when scanning on its own, may be able to determine the devices and corresponding services in its radio frequency (RF) proximity only. Thus, the range of discovery over which the services may be discovered is substantially increased. Further, the deployment of base station for D2D discovery enables intelligent monitoring of the user devices. For instance, the base station may alert two users connected through a social networking service, such as a friend application or a social networking website, when the corresponding user devices are in vicinity of each other. [0021] It should be noted that the description and figures merely illustrate the principles of the present subject matter. It will thus be appreciated that those skilled in the art will be able to devise various arrangements that, although not explicitly described or shown herein, embody the principles of the present subject matter and are included within its spirit and scope. Further, all examples recited herein are principally intended expressly to be only for pedagogical purposes to aid the reader in understanding the principles of the present subject matter and the concepts contributed by the inventor(s) to furthering the art, and are to be construed as being without limitation to such specifically recited examples and conditions. Moreover, all statements herein reciting principles, aspects, and embodiments of the present subject matter, as well as specific examples thereof, are intended to encompass equivalents thereof. [0022] The manner in which the systems and the methods for D2D communication shall be implemented has been explained in details with respect to the Figures 1-3. While aspects of described systems and methods for D2D communication can be implemented in any number of different computing systems, transmission environments, and/or configurations, the embodiments are described in the context of the following exemplary system(s). [0023] Figure 1 illustrates a network environment 100 for device to device (D2D) communication. The network environment 100 includes one or more user devices 102-1, 102-2, 102-3, and 102-N, hereinafter collectively referred to as the user devices 102 and individually referred to as the user device 102, through a network 104, according to an embodiment of the present subject matter. [0024] The user devices 102 may be defined as User Equipments (UEs) used by users to communicate with each other. Examples of the user devices 102 include, without limitation, mobile phones, landline phones, desktop computers, hand-held devices, laptops or other portable computers, network computers, and the like. Each of the user devices 102 work on a communication protocol as defined by the communication network to which the user device 102 is coupled. In one implementation, the user devices 102 may communicate with each other for availing services, such as gaming, music broadcast, location services, printing, content sharing, and the like in D2D communication mode. The D2D communication involves direct communication between the user devices 102 without using network resources, such as a base station 106. [0025] The network 104 may be a wireless network, or a combination of wired and wireless networks. The network 104 can be a collection of individual networks, interconnected with each other and functioning as a single large network (e.g., the internet or an intranet). Examples of such individual networks include, but are not limited to, 3rd Generation Partnership Project (3GPP), Long Term Evolution (LTE), and the like. Further, depending on the technology, the network 104 may include various network entities, such as gateways, routers; however, such details have been omitted for ease of understanding. The network 104 further comprises the base station 106. In one implementation, the base station 106 enables communication between the user devices 102 over the network 104.

[0026] According to an embodiment of the present subject matter, one or more user devices 102 may offer several services, such as gaming, content sharing, music broadcast, video broadcast, printing, location based services, advertisement messages, and the like in a D2D communication mode. The D2D communication involves direct communication between two user devices, in proximity of each other, without using conventional wireless communication networks and network elements thereof. In said embodiment, a user may seek to avail any of the services available in the D2D communication mode through a corresponding user device, such as the user device 102-1. For the sake of clarity, and not as a limitation, in a case where the user devices 102 may offer any of the aforementioned services, the user devices 102 may be referred to as the service offering devices 102. Further, where the user may avail any of the aforementioned services through any of the user devices 102 corresponding to the user, the user devices 102 may be referred to as the service availing devices 102. In one implementation, the base station 106 facilitates a D2D discovery mechanism for enabling the service availing device 102 to establish a D2D link with the service offering device 102 to avail the services offered by the service offering device 102.

[0027] In one implementation, the user device 102 and the base station 104 include processors 108-1 and 108-2, respectively. The processors 108-1 and 108-2, hereinafter collectively referred to as the processor 108, may be implemented as one or more microprocessors, microcomputers, microcontrollers, digital signal processors, central processing units, state machines, logic circuitries, and/or any devices that manipulate signals based on operational instructions. Among other capabilities, the processor(s) is configured to fetch and execute computer-readable instructions stored in the memory. [0028] The functions of the various elements shown in the figure, including any functional blocks labeled as "processor(s)", may be provided through the use of dedicated hardware as well as hardware capable of executing software in association with appropriate software. When provided by a processor, the functions may be provided by a single dedicated processor, by a single shared processor, or by a plurality of individual processors, some of which may be shared.

[0029] Also, the user device 102 and the base station 104 include I/O interface(s) 110-1 and 110-2, respectively. The I/O interfaces 110-1 and 110-2, collectively referred to as I/O interfaces 110 may include a variety of software and hardware interfaces that allow the user device 102 and the base station 104 to interact with the network 106, or with each other. Further, the I/O interfaces 110 may enable the user device 102 and the base station 104 to communicate with other communication and computing devices, such as web servers and external repositories. The user device 102 and the base station 104 may further include memory 112-1, and 112-2, respectively, collectively referred to as memory 112. The memory 112-1 and 112-2 may be coupled to the processor 108-1, and the processor 108-2, respectively. The memory 112 may include any computer-readable medium known in the art including, for example, volatile memory (e.g., RAM), and/or non-volatile memory (e.g., EPROM, flash memory, etc.).

[0030] The user device 102 and the base station 104 include modules 114-1, 114-2 and data 116-1, 116-2, respectively, collectively referred to as modules 114 and data 116, respectively. The modules 114 include routines, programs, objects, components, data structures, and the like, which perform particular tasks or implement particular abstract data types. The modules 114 further include modules that supplement applications on the user device 102 and the base station 104, for example, modules of an operating system.

[0031] Further, the modules 114 can be implemented in hardware, instructions executed by a processing unit, or by a combination thereof. The processing unit can comprise a computer, a processor, such as the processor 108, a state machine, a logic array or any other suitable devices capable of processing instructions. The processing unit can be a general-purpose processor which executes instructions to cause the general-purpose processor to perform the required tasks or, the processing unit can be dedicated to perform the required functions. [0032] In another aspect of the present subject matter, the modules 114 may be machine- readable instructions (software) which, when executed by a processor/processing unit, perform any of the described functionalities. The machine-readable instructions may be stored on an electronic memory device, hard disk, optical disk or other machine-readable storage medium or non-transitory medium. In one implementation, the machine-readable instructions can be also be downloaded to the storage medium via a network connection. The data 116 serves, amongst other things, as a repository for storing data that may be fetched, processed, received, or generated by one or more of the modules 114.

[0033] In an implementation, the modules 114-1 of the user device 102 include an interaction module 118, an analysis module 120, and other module(s) 122. In said implementation, the data 116-1 of the user device 102 includes interaction data 124, analysis data 126, and other data 128. The other module(s) 122 may include programs or coded instructions that supplement applications and functions, for example, programs in the operating system of the user device 102. The other data 128 comprise data corresponding to one or more other module(s) 122. [0034] Similarly, in an implementation, the modules 114-2 of the base station 104 include a registration module 130, a broadcast module 132, and other module(s) 134. In said implementation, the data 116-2 of the base station 104 includes registration data 136, broadcast data 138, and other data 140. The other module(s) 134 may include programs or coded instructions that supplement applications and functions, for example, programs in the operating system of the base station 104. The other data 140 comprise data corresponding to one or more other module(s) 134.

[0035] In one implementation, a user may seek to avail at least one service in the D2D communication mode through a corresponding service availing device 102. For the purpose, the interaction module 118 may send a registration request to the registration module 130. In one implementation, the registration request may include identity credentials, such as an internet protocol (IP) address, a media access control (MAC) address, and device identity.

[0036] Similarly, one or more service offering devices 102 may initially register with a network operator for offering the services in the D2D communication mode. For the purpose, the interaction module 118 may send the registration request to the registration module 130. In said implementation, the registration request may include identity credentials of the service offering devices 102, a service name of the service being offered, and service information. The service name and the service information may, together or individually, be referred to as service details. In one example, the service information may include at least one of a type, a quality of service parameter, and a service discovery range. The service discovery range as used herein indicates a desired range, of area, over which the service may be discovered and availed by the service availing devices 102. For example, a service offering device 102-1 may wish to be discovered across multiple cells and thus may specify the service discovery range accordingly.

[0037] In one implementation, the user device 102 may register both as the service offering device and the service availing device in case the user of the user device 102 seeks to avail certain services and offer certain other services.

[0038] Upon receiving the registration request, from the user devices 102, the registration module 130 may subsequently authenticate and register the service offering devices 102 and the service availing devices 102 based on identity credentials included in the registration request. In one implementation, the registration module 130 may register the service availing devices 102 and the service offering devices 102 in separate listings.

[0039] Upon successful registration of each of the service offering devices 102, the registration module 130 may generate a service list based on the registration request. In one implementation, the service list may include the service names of the services being offered. In another implementation, the service list may include the service names and the service information corresponding to each of the service name included in the service list. For instance, the service list may include service names like abc, xyz, and pqr and corresponding service information like music broadcast, gaming, and printing. Thus, the service information may aid the user in selecting a particular service from the service list. Further, the registration module 130 may maintain a service record for keeping a record of the one or more services being offered and the corresponding service offering devices 102 associated with each of the service. In one implementation, the registration module 130 may store the service list and the service record in the registration data 136. [0040] In one implementation, the service list may include both, the services being offered in the RF proximity and the services being offered in the nearby geographical region of the service availing devices.

[0041] Upon generation of service list, the broadcast module 132 may broadcast the service list to enable the service availing devices 102 to select a service they may wish to avail. In one implementation, the broadcast module 132 may broadcast the service list periodically, say, on hourly basis. In another implementation, the broadcast module 132 may broadcast the service list at predetermined time durations of a day. In yet another implementation, the broadcast module 132 may broadcast the service list either upon detecting presence of a new user device 102 in the vicinity or upon each updation of the service list. For the purpose, the broadcast module may obtain the service list stored in the registration data 136 and may subsequently transmit the service list.

[0042] In one implementation, the interaction module 118 of the service availing devices, say a service availing device 102-1, in vicinity of the base station 106 may receive and store the service list in the interaction data 124. Upon receiving the service list, the user may seek to avail a particular service, in the RF proximity or the nearby geographical region, included in the service list and may provide a user input for selecting the service name. Based on the user input, the analysis module 120 may generate a service request including request details, such as the service name and the service type which the user may wish to seek. The analysis module 120 may subsequently transmit the service request to the broadcast module 132. [0043] Upon receiving the service request, the broadcast module 132 may store the service request in the broadcast data 138. Based on the service requested, the broadcast module 132 may ascertain at least one service offering device, say a service offering device 102-2 from the corresponding offering devices 102 associated with the service. The broadcast module 132 may obtain the service record stored in the registration data 136 and may subsequently select the service offering device 102-2 based on the service information associated with the service offering device 102-2. In another implementation, the broadcast module 132 may select more than one service offering devices 102 from the one or more service offering devices 102. Subsequently, the broadcast module may generate a link message. In one implementation, the link message may include identity credentials of the service availing device 102-1 and the identity credentials and the service information of the service offering device 102-2. In another implementation, where the broadcast module 132 may select more than one service offering device 102, the link message may include the identity credentials and the service information corresponding to each of the selected service offering device 102.

[0044] Subsequently, the broadcast module 132 may transmit the link message to the service availing device 102-1 and the service offering device 102-2 for establishing the D2D link. Thereafter, the service availing device 102-1 may establish the D2D link with the at least one service offering device 102 based on the identity credentials of the service offering device 102-2 included in the link message. As mentioned previously, the service availing device 102-1 may seek to avail a service in the nearby geographical region. In such a case, the service availing device 102-1 may move in the RF proximity of the service offering device and then subsequently establish the D2D link with the service offering device 102-2.

[0045] In another implementation, the broadcast module 132 may transmit the link message to the service availing device 102-1 and each of the selected service offering devices 102. Upon receiving the link message, in one case, any of the selected service offering devices 102 may initiate the D2D link establishment based on the identity credentials of the service availing device 102-1. In another case, the service availing device 102-1 may select the at least one service offering device 102 from the selected service offering devices 102 based on the service information included in the link message and may subsequently establish the D2D link with the at least one service offering device 102. [0046] In another embodiment, upon successful registration with the network operator and before receiving the service list, the user may wish to seek a particular service, for example, a printing service. For the purpose, the interaction module 118 may transmit the service request to the broadcast module 132. In one implementation, the service request may include the service information corresponding to the service the user may wish to seek. For instance, in the previous example of printing service, the service request may include the type of service as printing service. In another implementation, the service request may include the service name. For example in a case where the user may seek to play a particular game, the service request may include the name of the game. [0047] Upon receiving the service request, the broadcast module 132 may scan the service list stored in the broadcast data 138 and ascertain the availability of the service. Further, in an implementation, the broadcast module 132 may scan the broadcast data to determine whether a new service has been registered which may not have been included in the service list. In a case, where the broadcast module 132 ascertains that the service is available, the broadcast module 132 may subsequently provide the link message to the service availing device 102-1 in a manner as described above. Further, in the case where the service has not been updated in the service list, the broadcast module 132 may update the service list. The service availing device 102-1 may then establish a D2D link with a service offering device, say service offering device 102-2 to avail the printing service. [0048] In another embodiment, where the D2D link needs to be established in a haste, the base station 106 may reserve one or more channel resources from the pool of channels for such quick D2D link establishment. For instance, two users travelling in different vehicles, in close proximity of each other, may seek to establish a D2D link for sharing content amongst themselves Subsequently, upon receiving the registration request from the service availing device 102-1 and the service offering device 102-2 seeking to establish the D2D link in said embodiment, the base station 104 may transmit channel information corresponding to the reserved channel resources to the service availing device 102-1 and the service offering device 102-2. The service availing device 102-1 and the service offering device 102-2 may subsequently establish the D2D link over the reserved channel resources. [0049] In yet another embodiment, the service offering device 102-2 may provide relay services that the service availing device 102-1 may wish to seek. For example, the service offering device 102-2 may wish to act as a transmitter, such as a wireless router, for transmitting data packets received from the base station 106 to the service availing device 102-1. In such a case, upon successful registration, the broadcast module 132 may transmit a link message to the service availing device 102-1 and the service offering device 102-2. In such a case, the link message may include the identity credentials of both the service availing device 102-1 and the service offering device 102-2. Upon receiving the link message, either of the service availing device 102-1 and the service offering device 102-2 may subsequently initiate the D2D link establishment based on the link message. [0050] Figure 2 illustrates a method 200 for device to device (D2D) discovery, according to an embodiment of the present subject matter. Figure 3 illustrates a method 300 for establishing a D2D link, according to an embodiment of the present subject matter.

[0051] The order in which the methods 200 and 300 are described is not intended to be construed as a limitation, and any number of the described method blocks can be combined in any order to implement methods 200 and 300, or an alternative method. Additionally, individual blocks may be deleted from the methods 200 and 300 without departing from the spirit and scope of the subject matter described herein. Furthermore, the methods 200 and 300 may be implemented in any suitable hardware, machine readable instructions, firmware, or combination thereof. [0052] A person skilled in the art will readily recognize that steps of the methods 200 and

300 can be performed by programmed computers. Herein, some examples are also intended to cover program storage devices and non-transitory computer readable medium, for example, digital data storage media, which are machine or computer readable and encode machine- executable or computer-executable instructions, where said instructions perform some or all of the steps of the described methods 200 and 300. The program storage devices may be, for example, digital memories, magnetic storage media, such as a magnetic disks and magnetic tapes, hard drives, or optically readable digital data storage media.

[0053] With reference to Figure 2, at block 202, a service list including details of one or more services is broadcasted. In one implementation, one or more service offering devices may offer several services, such as gaming, printing, music broadcast, location based services, and video broadcast in a device to device (D2D) communication mode. Further, a service availing device may seek to avail any of the services. For the purpose, both the service availing device and the service offering device may register with the network operator. Thereafter, the service list may be generated based on the services being offered by the service offering devices. The service list may include one or more services, such that each of the one or more services is provided by the one or more service offering devices associated with the service. In one implementation, the service list may be broadcasted by a base station of the network operator. For example, the base station 104 may broadcast the service list after a predetermined interval. [0054] At block 204, a service request from a service availing device is received. In one implementation, a user may seek to avail a service enlisted in the service list. For the purpose, the user may send a service request through a corresponding service availing device. The service request may indicate the service which the user may wish to seek. In one implementation, the base station 104 may receive the service request. [0055] At block 206, a link message is provided based on the service request. In one implementation, upon receiving the service request, at least one service offering device, from amongst the one or more service offering device, associated with the service included in the service request is ascertained. Thereafter, a link message is provided to the service availing device and the at least one service offering device. The link message may include identity credentials of the service availing device and the at least one service offering device. Subsequently, either of the service availing device and the at least one service offering device may initiate the device discovery mechanism based on the link message for establishing a D2D link amongst themselves. In another implementation, identity credentials of one or more service offering devices, offering the service, may be provided in the link message along with the identity credentials of the service availing device. In such a case, the D2D link may be established between the service availing device and any one of the service offering device.

[0056] As described previously, figure 3 illustrates a method for establishing a D2D link.

With reference to figure 3, at block 302, a registration is performed with a base station for availing services in device to device communication mode. In one implementation, a registration request may be sent for registering a service availing device in order to avail services in the D2D communication mode. The registration request may include identity credentials, such as an IP address, a MAC address, and device identity. Upon receiving the registration request, the device may be registered. In one implementation, the base station 104 may receive a registration request from the service availing device 102-1. [0057] At block 304, a service list is obtained from the base station. Upon successful registration of the service availing device, a service list is obtained. In one example, the service list may include service details of one or more services, where each of the one or more service is provided by one or more service offering devices associated with the service. In one example, the service availing device 102-1 may obtain the service list broadcasted by the base station 106. [0058] At block 306, a service request is provided. In one example, a user may select a service from the service list. Subsequently, a service request may be sent to the base station. The service request may indicate the selected service. In one example, the service availing device 102-1 may send the service request to the base station 106.

[0059] At block 308, a link message based on the service request is received. Upon receiving the service request, a link message including identity credentials of at least one service offering device associated with the service and the identity credentials of the service availing device is received by the service availing device.

[0060] At block 310, a D2D link is established. Based on the identity credentials included in the link message, the D2D link is established between the service availing device and the at least one service offering device. In one implementation, the service availing device may initiate the process of establishment of the D2D link. In another implementation, the at least one service offering device from amongst the one or more service offering devices may initiate the D2D link establishment upon receiving the link message.

[0061] Although embodiments for methods and systems for D2D communication have been described in a language specific to structural features and/or methods, it is to be understood that the invention is not necessarily limited to the specific features or methods described. Rather, the specific features and methods are disclosed as exemplary embodiments for D2D communication.

Claims

A method for device to device (D2D) discovery, the method comprising:

receiving, by a base station (106), a service request from a service availing device (102) seeking to avail at least one service, wherein the service request indicates the at least one service; and

providing, by the base station (106), a link message to the service availing device (102) and at least one service offering device (102) associated with the at least one service, based on the service request, for initiating device discovery to establish a D2D link for availing the at least one service.

The method as claimed in claim 1, wherein the method further comprises:

receiving, by the base station (106), a registration request from each of the one or more service offering devices (102), wherein the registration request includes at least one of an identity credentials, service name, and service information, and wherein the service information includes at least one of a name, a type, a quality of service, and a service discovery range; and

registering, by the base station (106), each of the one or more service offering devices (102) based on the corresponding identity credentials included in the registration request. The method as claimed in any of the preceding claims, wherein the method further comprises broadcasting, by the base station (106), a service list including service details of one or more services offered by the one ore more service offering devices (102) registered with the base station (106), wherein each of the one or more services is provided by one or more service offering devices (102) associated with the service.

The method as claimed in claim 3, wherein the method further comprises generating the service list based on the registration request.

The method as claimed in any of the preceding claims, wherein the service details include at least one of the service name and the service information.

6. The method as claimed in claim 1, wherein the method further comprises ascertaining, by the base station (106), availability of the at least one service using a service record stored in the base station (106), based on the service request.

7. A method for device to device (D2D) discovery, the method comprises:

providing, by a service availing device (102), a service request for availing at least one service to a base station (106), wherein the service request indicates the at least one service;

receiving, by the service availing device (102), a link message for initiating device discovery with at least one service offering device (102) associated with the at least one service, based on the service request, to establish a D2D link for availing the at least one service.

8. The method as claimed in claim 7, wherein the method further comprises obtaining, by the service availing device (102), a service list including service details of one or more services from a base station (106), wherein each of the one or more services is provided by one or more service offering devices (102) associated with the service.

9. The method as claimed in claim 7, wherein the method further comprises establishing, by the service availing device (102), the D2D link with the at least one service offering device (102) associated with the at least one service.

10. The method as claimed in claim 7, wherein the providing further comprises selecting the at least one service based on a user input.

11. The method as claimed in claim 7, wherein the method further comprises sending, by the service availing device (102), a registration request for registering with the base station (106), wherein the registration request includes at least one of an identity credentials, service name, and service information, and wherein the service information includes at least one of a name, a type, a quality of service, and a service discovery range.

12. A base station (106) comprising:

a processor (108-2);

an broadcast module (132) coupled to the processor (108-2) to,

receive a service request from a service availing device (102) seeking to avail at least one service, wherein the service request indicates the at least one service; and provide a link message to the service availing device (102) and at least one service offering device (102) associated with the at least one service, based on the service request, for initiating device discovery to establish a D2D link for availing the at least one service.

13. The base station (106) as claimed in claim 12, wherein the base station (106) further comprises a registration module (130) coupled to the processor (108-2) to,

receive a registration request from the service availing device (102) and each of the one or more service offering devices (102), wherein the registration request includes at least one of an identity credentials, a service name, and a service information; and

register the service availing device (102) and the one or more service offering device based on the identity credentials.

14. The base station (106) as claimed in claim 12, wherein the broadcast module (132) further,

generates a service list based on the registration request, wherein the service list includes service details of one or more services offered by one or more service offereing devices registered with the base station (106), wherein each of the one or more services is provided by one or more service offering devices (102) associated with the service; and broadcasts the service list.

15. The base station (106) as claimed in claim 12, wherein the broadcast module (132) further ascertaining, by the base station (106), availability of the at least one service based on a service record stored in the base station (106).

16. A computer-readable medium having embodied thereon a computer program for device to device (D2D) discovery, the method comprising:

receiving a service request from a service availing device seeking to avail at least one service, wherein the service request indicates the at least one service; and

providing a link message to the service availing device and at least one service offering device associated with the at least one service, based on the service request, for initiating device discovery to establish a D2D link for availing the at least one service.