Patent ID: 12238621

DETAILED DESCRIPTION

FIG.1Ais a diagram of an example communications system100in which one or more disclosed embodiments may be implemented. The communications system100may be a multiple access system that provides content, such as voice, data, video, messaging, broadcast, etc., to multiple wireless users. The communications system100may enable multiple wireless users to access such content through the sharing of system resources, including wireless bandwidth. For example, the communications systems100may employ one or more channel access methods, such as code division multiple access (CDMA), time division multiple access (TDMA), frequency division multiple access (FDMA), orthogonal FDMA (OFDMA), single-carrier FDMA (SC-FDMA), and the like.

As shown inFIG.1A, the communications system100may include wireless/wired transmit/receive units (WTRUs)102a,102b,102c,102d, a radio access network (RAN)104, a core network106, a public switched telephone network (PSTN)108, the Internet110, and other networks112, though it will be appreciated that the disclosed embodiments contemplate any number of WTRUs, base stations, networks, and/or network elements. Each of the WTRUs102a,102b,102c,102dmay be any type of device configured to operate and/or communicate in a wireless environment. By way of example, the WTRUs102a,102b,102c,102dmay be configured to transmit and/or receive wireless/wired signals and may include user equipment (UE), a mobile station, a fixed or mobile subscriber unit, a pager, a cellular telephone, a personal digital assistant (PDA), a smartphone, a laptop, a netbook, a personal computer, a wireless sensor, consumer electronics, an infrastructure node, and the like.

The communications systems100may also include a base station114aand a base station114b. Each of the base stations114a,114bmay be any type of device configured to wirelessly interface with at least one of the WTRUs102a,102b,102c,102dto facilitate access to one or more communication networks, such as the core network106, the Internet110, and/or the other networks112. By way of example, the base stations114a,114bmay be a base transceiver station (BTS), a Node-B, an eNode B, a Home Node B, a Home eNode B, a site controller, an access point (AP), a wireless router, and the like. While the base stations114a,114bare each depicted as a single element, it will be appreciated that the base stations114a,114bmay include any number of interconnected base stations and/or network elements.

The base station114amay be part of the RAN104, which may also include other base stations and/or network elements (not shown), such as a base station controller (BSC), a radio network controller (RNC), relay nodes, etc. The base station114aand/or the base station114bmay be configured to transmit and/or receive wireless signals within a particular geographic region, which may be referred to as a cell (not shown). The cell may further be divided into cell sectors. For example, the cell associated with the base station114amay be divided into three sectors. Thus, in one embodiment, the base station114amay include three transceivers, i.e., one for each sector of the cell. In another embodiment, the base station114amay employ multiple-input multiple-output (MIMO) technology and, therefore, may utilize multiple transceivers for each sector of the cell.

The base stations114a,114bmay communicate with one or more of the WTRUs102a,102b,102c,102dover an air interface116, which may be any suitable wireless communication link (e.g., radio frequency (RF), microwave, infrared (IR), ultraviolet (UV), visible light, etc.). The air interface116may be established using any suitable radio access technology (RAT).

More specifically, as noted above, the communications system100may be a multiple access system and may employ one or more channel access schemes, such as CDMA, TDMA, FDMA, OFDMA, SC-FDMA, and the like. For example, the base station114ain the RAN104and the WTRUs102a,102b,102cmay implement a radio technology such as Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access (UTRA), which may establish the air interface116using wideband CDMA (WCDMA). WCDMA may include communication protocols such as High-Speed Packet Access (HSPA) and/or Evolved HSPA (HSPA+). HSPA may include High-Speed Downlink Packet Access (HSDPA) and/or High-Speed Uplink Packet Access (HSUPA).

In another embodiment, the base station114aand the WTRUs102a,102b,102cmay implement a radio technology such as Evolved UMTS Terrestrial Radio Access (E-UTRA), which may establish the air interface116using Long Term Evolution (LTE) and/or LTE-Advanced (LTE-A).

In other embodiments, the base station114aand the WTRUs102a,102b,102cmay implement radio technologies such as IEEE 802.16 (i.e., Worldwide Interoperability for Microwave Access (WiMAX)), CDMA2000, CDMA2000 1×, CDMA2000 EV-DO, Interim Standard 2000 (IS-2000), Interim Standard 95 (IS-95), Interim Standard 856 (IS-856), Global System for Mobile communications (GSM), Enhanced Data rates for GSM Evolution (EDGE), GSM EDGE (GERAN), and the like.

The base station114binFIG.1Amay be a wireless router, Home Node B, Home eNode B, or access point, for example, and may utilize any suitable RAT for facilitating wireless connectivity in a localized area, such as a place of business, a home, a vehicle, a campus, and the like. In one embodiment, the base station114band the WTRUs102c,102dmay implement a radio technology such as IEEE 802.11 to establish a wireless local area network (WLAN). In another embodiment, the base station114band the WTRUs102c,102dmay implement a radio technology such as IEEE 802.15 to establish a wireless personal area network (WPAN). In yet another embodiment, the base station114band the WTRUs102c,102dmay utilize a cellular-based RAT (e.g., WCDMA, CDMA2000, GSM, LTE, LTE-A, etc.) to establish a picocell or femtocell. As shown inFIG.1A, the base station114bmay have a direct connection to the Internet110. Thus, the base station114bmay not be required to access the Internet110via the core network106.

The RAN104may be in communication with the core network106, which may be any type of network configured to provide voice, data, applications, and/or voice over internet protocol (VoIP) services to one or more of the WTRUs102a,102b,102c,102d. For example, the core network106may provide call control, billing services, mobile location-based services, pre-paid calling, Internet connectivity, video distribution, etc., and/or perform high-level security functions, such as user authentication. Although not shown inFIG.1A, it will be appreciated that the RAN104and/or the core network106may be in direct or indirect communication with other RANs that employ the same RAT as the RAN104or a different RAT. For example, in addition to being connected to the RAN104, which may be utilizing an E-UTRA radio technology, the core network106may also be in communication with another RAN (not shown) employing a GSM radio technology.

The core network106may also serve as a gateway for the WTRUs102a,102b,102c,102dto access the PSTN108, the Internet110, and/or other networks112. The PSTN108may include circuit-switched telephone networks that provide plain old telephone service (POTS). The Internet110may include a global system of interconnected computer networks and devices that use common communication protocols, such as the transmission control protocol (TCP), user datagram protocol (UDP) and the internet protocol (IP) in the TCP/IP internet protocol suite. The networks112may include wired or wireless communications networks owned and/or operated by other service providers. For example, the networks112may include another core network connected to one or more RANs, which may employ the same RAT as the RAN104or a different RAT.

Some or all of the WTRUs102a,102b,102c,102din the communications system100may include multi-mode capabilities, i.e., the WTRUs102a,102b,102c,102dmay include multiple transceivers for communicating with different wireless networks over different wireless links. For example, the WTRU102cshown inFIG.1Amay be configured to communicate with the base station114a, which may employ a cellular-based radio technology, and with the base station114b, which may employ an IEEE 802 radio technology.

FIG.1Bis a system diagram of an example WTRU102. As shown inFIG.1B, the WTRU102may include a processor118, a transceiver120, a transmit/receive element122, a speaker/microphone124, a keypad126, a display/touchpad128, non-removable memory130, removable memory132, a power source134, a global positioning system (GPS) chipset136, and other peripherals138. It will be appreciated that the WTRU102may include any sub-combination of the foregoing elements while remaining consistent with an embodiment.

The processor118may be a general purpose processor, a special purpose processor, a conventional processor, a digital signal processor (DSP), a plurality of microprocessors, one or more microprocessors in association with a DSP core, a controller, a microcontroller, Application Specific Integrated Circuits (ASICs), Field Programmable Gate Array (FPGAs) circuits, any other type of integrated circuit (IC), a state machine, and the like. The processor118may perform signal coding, data processing, power control, input/output processing, and/or any other functionality that enables the WTRU102to operate in a wireless environment. The processor118may be coupled to the transceiver120, which may be coupled to the transmit/receive element122. WhileFIG.1Bdepicts the processor118and the transceiver120as separate components, it will be appreciated that the processor118and the transceiver120may be integrated together in an electronic package or chip.

The transmit/receive element122may be configured to transmit signals to, or receive signals from, a base station (e.g., the base station114a) over the air interface116. For example, in one embodiment, the transmit/receive element122may be an antenna configured to transmit and/or receive RF signals. In another embodiment, the transmit/receive element122may be an emitter/detector configured to transmit and/or receive IR, UV, or visible light signals, for example. In yet another embodiment, the transmit/receive element122may be configured to transmit and receive both RF and light signals. It will be appreciated that the transmit/receive element122may be configured to transmit and/or receive any combination of wireless signals.

In addition, although the transmit/receive element122is depicted inFIG.1Bas a single element, the WTRU102may include any number of transmit/receive elements122. More specifically, the WTRU102may employ MIMO technology. Thus, in one embodiment, the WTRU102may include two or more transmit/receive elements122(e.g., multiple antennas) for transmitting and receiving wireless signals over the air interface116.

The transceiver120may be configured to modulate the signals that are to be transmitted by the transmit/receive element122and to demodulate the signals that are received by the transmit/receive element122. As noted above, the WTRU102may have multi-mode capabilities. Thus, the transceiver120may include multiple transceivers for enabling the WTRU102to communicate via multiple RATs, such as UTRA and IEEE 802.11, for example.

The processor118of the WTRU102may be coupled to, and may receive user input data from, the speaker/microphone124, the keypad126, and/or the display/touchpad128(e.g., a liquid crystal display (LCD) display unit or organic light-emitting diode (OLED) display unit). The processor118may also output user data to the speaker/microphone124, the keypad126, and/or the display/touchpad128. In addition, the processor118may access information from, and store data in, any type of suitable memory, such as the non-removable memory130and/or the removable memory132. The non-removable memory130may include random-access memory (RAM), read-only memory (ROM), a hard disk, or any other type of memory storage device. The removable memory132may include a subscriber identity module (SIM) card, a memory stick, a secure digital (SD) memory card, and the like. In other embodiments, the processor118may access information from, and store data in, memory that is not physically located on the WTRU102, such as on a server or a home computer (not shown).

The processor118may receive power from the power source134, and may be configured to distribute and/or control the power to the other components in the WTRU102. The power source134may be any suitable device for powering the WTRU102. For example, the power source134may include one or more dry cell batteries (e.g., nickel-cadmium (NiCd), nickel-zinc (NiZn), nickel metal hydride (NiMH), lithium-ion (Li-ion), etc.), solar cells, fuel cells, and the like.

The processor118may also be coupled to the GPS chipset136, which may be configured to provide location information (e.g., longitude and latitude) regarding the current location of the WTRU102. In addition to, or in lieu of, the information from the GPS chipset136, the WTRU102may receive location information over the air interface116from a base station (e.g., base stations114a,114b) and/or determine its location based on the timing of the signals being received from two or more nearby base stations. It will be appreciated that the WTRU102may acquire location information by way of any suitable location-determination method while remaining consistent with an embodiment.

The processor118may further be coupled to other peripherals138, which may include one or more software and/or hardware modules that provide additional features, functionality and/or wired or wireless connectivity. For example, the peripherals138may include an accelerometer, an e-compass, a satellite transceiver, a digital camera (for photographs or video), a universal serial bus (USB) port, a vibration device, a television transceiver, a hands free headset, a Bluetooth® module, a frequency modulated (FM) radio unit, a digital music player, a media player, a video game player module, an Internet browser, and the like.

FIG.1Cis a system diagram of the RAN104and the core network106according to an embodiment. As noted above, the RAN104may employ an E-UTRA radio technology to communicate with the WTRUs102a,102b,102cover the air interface116. The RAN104may also be in communication with the core network106.

The RAN104may include eNode-Bs140a,140b,140c, though it will be appreciated that the RAN104may include any number of eNode-Bs while remaining consistent with an embodiment. The eNode-Bs140a,140b,140cmay each include one or more transceivers for communicating with the WTRUs102a,102b,102cover the air interface116. In one embodiment, the eNode-Bs140a,140b,140cmay implement MIMO technology. Thus, the eNode-B140a, for example, may use multiple antennas to transmit wireless signals to, and receive wireless signals from, the WTRU102a.

Each of the eNode-Bs140a,140b,140cmay be associated with a particular cell (not shown) and may be configured to handle radio resource management decisions, handover decisions, scheduling of users in the uplink and/or downlink, and the like. As shown inFIG.1C, the eNode-Bs140a,140b,140cmay communicate with one another over an X2 interface.

The core network106shown inFIG.1Cmay include a mobility management entity gateway (MME)142, a serving gateway144, and a packet data network (PDN) gateway146. While each of the foregoing elements are depicted as part of the core network106, it will be appreciated that any one of these elements may be owned and/or operated by an entity other than the core network operator.

The MME142may be connected to each of the eNode-Bs140a,140b,140cin the RAN104via an S1 interface and may serve as a control node. For example, the MME142may be responsible for authenticating users of the WTRUs102a,102b,102c, bearer activation/deactivation, selecting a particular serving gateway during an initial attach of the WTRUs102a,102b,102c, and the like. The MME142may also provide a control plane function for switching between the RAN104and other RANs (not shown) that employ other radio technologies, such as GSM or WCDMA.

The serving gateway144may be connected to each of the eNode Bs140a,140b,140cin the RAN104via the S1 interface. The serving gateway144may generally route and forward user data packets to/from the WTRUs102a,102b,102c. The serving gateway144may also perform other functions, such as anchoring user planes during inter-eNode B handovers, triggering paging when downlink data is available for the WTRUs102a,102b,102c, managing and storing contexts of the WTRUs102a,102b,102c, and the like.

The serving gateway144may also be connected to the PDN gateway146, which may provide the WTRUs102a,102b,102cwith access to packet-switched networks, such as the Internet110, to facilitate communications between the WTRUs102a,102b,102cand IP-enabled devices.

The core network106may facilitate communications with other networks. For example, the core network106may provide the WTRUs102a,102b,102cwith access to circuit-switched networks, such as the PSTN108, to facilitate communications between the WTRUs102a,102b,102cand traditional land-line communications devices. For example, the core network106may include, or may communicate with, an IP gateway (e.g., an IP multimedia subsystem (IMS) server) that serves as an interface between the core network106and the PSTN108. In addition, the core network106may provide the WTRUs102a,102b,102cwith access to the networks112, which may include other wired or wireless networks that are owned and/or operated by other service providers.

Other network112may further be connected to an IEEE 802.11 based wireless local area network (WLAN)160. The WLAN 160 may include an access router165. The access router may contain gateway functionality. The access router165may be in communication with a plurality of access points (APs)170a,170b. The communication between access router165and APs170a,170bmay be via wired Ethernet (IEEE 802.3 standards), or any type of wireless communication protocol. AP170ais in wireless communication over an air interface with WTRU102d.

V2X (vehicle to everything) communication may be employed in various architectures to enable communication of a vehicle to another point/node in a network. One possible embodiment as shown inFIG.2has a V2X architecture based on proximity service (ProSe) PC5 architecture. In another embodiment shown inFIG.3a V2X architecture may be based on enhanced multimedia broadcast multicast services (eMBMS).

In the example ofFIG.2the architecture may have a V2X Control Function for a public land mobile network PLMN A operator201connected via a V2 reference point to a V2X Application Server (AS)207. There may be other V2X Control Function PLMN B201, or any number n V2X Control Function PLMNs202that connect to the V2X Application Server207. The V2X Application server207may host/run a V2X application214. The V2X Control Function PLMNs202may serve as an intermediary between a WTRU205and the V2X Application server207. The WTRU205may be a vehicle. Another WTRU205or WTRU213may be in or a part of a vehicle. Another WTRU203may be operated and/or carried by a pedestrian. Another WTRU215may be stationary, like a Road Side Unit (RSU). Each WTRU203,205,206,213, or215may run a V2X application204,206,214, or216respectively. The EPC components may include a HSS209, MME210, S/P-GW211, a the E-UTRAN212and may facilitate communication with the various WTRUs203,205,206,213, or215. V2 may be a reference point between a V2X application and a V2X Control Function. V3 may be a reference point between a V2X enabled WTRU and a V2X Control Function. V4 may be a reference point between an HSS and a V2X Control Function. V5 may be a reference point between V2X applications. LTE-Uu may be a reference point between a V2X enabled WTRU and an E-UTRAN. PC5 may be a reference point between V2X enabled WTRUs Vehicle to Vehicle, Vehicle to Infrastructure, or Vehicle to Pedestrian communications.

FIG.3shows an example system diagram of a reference architecture for V2X communication based on evolved multimedia broadcast multicast services (eMBMS). In this example transmission, reception, or both of V2X messages may occur facilitated by an eMBMS architecture. The broadcast multicast service center (BM-SC)310may provide membership, session and transmission, proxy and transport, service announcement, security, and content synchronization. The BM-SC310communicates with the V2X Application Server311as the source of content for a multicast. An EPC may include an HSS303, MME305, S/P-GW306, and E-UTRAN308to facilitate communication over LTE for the V2X messages. A MBMS gateway (GW)309may perform MBMS session control signaling towards the E-UTRAN308, and sometimes via an MME305. Alternatively/additionally the MBMS GW309may distribute user plane data to eNBs part of the EPC using IP multicast. The E-UTRAN308communicates with a V2X enabled WTRU307. There may be a plurality of V2X WTRUs307and they may be a mixture of vehicles, pedestrians, or RSUs. A policy and charging rules function (PCRF)304may be connected to the S/P-GW306and/or the V2X Application Server311. Elements on the left side of the dotted line may be part of a H-PLMN301and the elements on the right side of the dotted line may be part of an Application Domain302. M1 may be a reference point between a MBMS GW and a E-UTRAN for MBMS data delivery where IP multicast may be used to forward data. M3 may be a reference point for the control plane between the MME and the E-UTRAN. Sm may be a reference point for the control plane between MME and the MBMS-GW. SGi-mb may be the reference point between BM-SC and the MBMS-GW function for MBMS data delivery. SGmb may be the reference point for a control plane between the BM-SC and the MBMS GW. Uu may be a reference point between a V2X enabled WTRU and an E-UTRAN. A Rx is an interface between application function (AF) and PCRF. A Gx is an interface between PCRF and PGW. A S6a is an interface between MME and HSS. A VMB2-C is a control plane interface between V2X application server and BMSC. A VMB2-U is a user plane interface between V2X app server and BMSC.

FIG.4is a system diagram of an example of V2X operation including a WTRU based RSU. A V2X Application401aoperating on a WTRU402a. In one example the WRTU402ais a part of or connected to a vehicle. The RSU403may include at least a V2X application401boperating on a stationary WTRU402bor a new standalone functional entity. A PC5 reference point may connect WTRU402aand WTRU402band a V5 reference point may connect the two instances of the V2X applications401aand401b.

FIG.5is a system diagram of an example of V2X operation including an eNode-B based RSU. While similar to the example shown inFIG.4in that a V2X application501aoperates on a WTRU502,FIG.5differs in that the RSU503may contain an eNode-B505operating a V2X application501bconnected to a local gateway (L-GW)504. A Uu reference point may connect the eNB505to the WTRU502and a V1 reference point may connect the two instances of the V2X application501aand502b.

FIG.6is a system diagram of an example of local network architecture for V2X services.FIG.6is similar to the example shown inFIG.3in that it may utilize an MBMS architecture. The BM-SC603may provide membership, session and transmission, proxy and transport, service announcement, security, and content synchronization. The BM-SC603may communicate with the V2X Application Server601as the source of content for a multicast. The L-GW/S-GW602may communicate with the V2X Application Server601to assist distributing a V2X broadcast to the MME604and/or eNB606. A MBMS GW605may distribute user plane data to eNB606, sometimes via the MME604. The eNB606communicates with a V2X enabled WTRU607aand/or607. There may be a plurality of V2X WTRUs307and they may be a mixture of vehicles, pedestrians, or RSUs. M1 may be a reference point between a MBMS GW and an eNB for MBMS data delivery where IP multicast may be used to forward data. M3 may be a reference point for the control plane between the MME and the E-UTRAN. Sm may be a reference point for the control plane between MME and the MBMS-GW. SGi-mb may be the reference point between BM-SC and the MBMS-GW function for MBMS data delivery. SGmb may be the reference point for a control plane between the BM-SC and the MBMS GW. LTE-Uu may be a reference point between a V2X enabled WTRU and an eNB. A S1-U is a userplane interface between eNB and SGW. A S1-C is a control plane interface between eNB and MME. A MB2 is an interface between application server and BMSC. A S11 is an interface between S-GW and MME.

FIG.7is a system diagram of an example of local MBMS network architecture for V2X services with a Local MCMS Entity (LME)708. As seen inFIG.7, the user plane related MBMS functions, such as, for example, the user plane functions of a BM-SC and the MBMS gateway (MBMS-GW) may be moved closer to the RAN712thanFIG.6since these functions would be internal to the LME708. LME708may contain similar functions as the core network (CN) MBMS Entity702. V2X messages may be distributed to target eNBs709, and ultimately to a WTRU710aand710b. The WTRU710aand710bmay be a pedestrian, a vehicle, or a RSU. By having an architecture with an LME708, V2X messages may be sent without traversing the core network nodes, for example, the BM-SC703, MBMS-GW704, and the MME705. The control plane may remain at the main MBMS nodes, i.e. BM-SC703, MBMS-GW704and MME705in the CN MBMS Entity702. Further, the LME708may host the necessary functions to transmit the data received directly from the Local V2X Server701to eNB709via M1 reference point (e.g., SYNC function, IP multicast distribution function and the like). The Multi Cell Coordination Entity (MCE)706may facilitate a connection between the CN MBMS Entity702and the eNB709. M1 may be a reference point between an MBMS GW and an eNB for MBMS data delivery where IP multicast may be used to forward data. M3 may be a reference point for the control plane between the MME and the MCE. M2 may be a reference point between an eNB and the MCE. SGmb may be the reference point for a control plane between the BM-SC and the MBMS GW. LTE-Uu may be a reference point between a V2X enabled WTRU and an eNB. A M2 is an interface between the MCE and eNB. A MB2-C is a control plane interface between BMSC and application server. A My is a new proposed interface between MBMS-GW and LME.

In one embodiment for a V2X communication system, configuration information may be used to enable V2X services. For a V2X WTRU to be able to access various V2X services it may need to be properly configured with various parameters by the network. The configuration information may either be pre-configured in the WTRU, sent by the V2X Control Function, V2X Application Server, or the multiple network nodes, e.g., an eNB or MME. By ensuring that V2X WTRUs are properly configured, a V2X communication system may enable the exchange of messages to and from a WTRU in a variety of situations, such as: when the WTRU is roaming and not-roaming; when the WTRU is served by an Evolved UMTS Terrestrial Radio Access Network (E-UTRAN) and when the WTRU is not served by an E-UTRAN; and when certain messages need to be prioritized to meet latency requirements.

Configuration information/parameters may be required to enable V2X services. The network may have to provide certain configuration parameters to the WTRU for the WTRU to be able to communicate to the network. Such configuration parameters may be pushed or facilitated by various network nodes including, but not limited to, an Access Network Discovery and Selection Function (ANDSF), a ProSe Function, an MME, an eNB and the like. The V2X WTRU may receive one or more configuration parameters from the aforementioned nodes and the V2X Control Function via a V3 interface, such as the V3 interface shown inFIG.2.

Configuration information/parameters may depend on the local network architecture, such as but not limited to the example network architectures as described herein. In the following examples, a V2X WTRU connects to a local network and receives configuration information/parameters associated with the local network architecture.

In one example, the V2X WTRU may be provided with an access point name (APN) of the local network for V2X communication. The V2X WTRU may use this APN information to request PDN connectivity to the local network which is designated for various V2X commination scenarios. The V2X WTRU may be configured with multiple APNs for different types of V2X communication, e.g., a specific APN for V2X safety communication and a different APN for non-safety communication.

In another example, the V2X WTRU may be provided with an LGW address or local home network (LHN) identity. The V2X WTRU may provide this information to the network (eNode-B, MME and the like) to facilitate the selection of the gateway responsible for the desired V2X communication.

In another example, the V2X WTRU may be provided with relay node information, such as a user information ID, a relay service code, a Layer 2 address, a Group ID and the like. The information of the relay node may be configured for both within E-UTRAN coverage and out of E-UTRAN coverage operation.

In another example, the V2X WTRU may be provided with a V2X Application Server address. Such information may include an address (for example, an IP address, a host name, a uniform resource identifier (URI) and the like) of V2X Application Server(s) for a particular V2X application.

In another example, the V2X WTRU may be provided with an address of the RSU(s). This address may be a specific broadcast address (Layer2 ID) which indicates that the message is directed for an RSU. Alternatively, the WTRU may be configured with RSU prefix(s) suggesting that the destination of the message is an RSU (either WTRU based or eNode-B based).

In another example, the V2X WTRU may be provided with geographic area information to be able to broadcast or disseminate the message(s) which are only relevant to a certain region. For example, the V2X WTRU may be provided with a broadcast number that may indicate the number of times the message should be rebroadcasted.

In another example, the V2X WTRU may be provided with QoS parameters for V2X operations. The QoS parameters may include, for example: mapping information from application level priority to V2X priority, bit rate information, QoS Class Indicator (QCI), PPPP value and the like. The QoS parameters may also be configured. In one instance, QoS and priority parameters may be assigned on a per V2X message basis (e.g., safety or non-safety). Also, different parameter sets may be configured for control messages and V2X data messages. In another instance, the V2X WTRU may be provided with TMGI or other MBMS service area ID (SAI) related information for V2X devices supporting MBMS architecture and receiving V2X messages via an MBMS broadcast.

The information or parameters described in the non-limiting examples above may be sent by the V2X Control Function, V2X Application Server, or other network nodes. These network nodes may send such information/parameters to the V2X WTRU before the start of the communication or during the V2X communication. Management objects (MOs) may be employed by the network nodes to push certain information to the V2X WTRU. In a case where the network employs MOs to send information to a WTRU, the WTRU may provide the MO information to the V2X layer in the protocol stack. In some cases the V2X layer in the WTRU may be the same or similar to the ProSe protocol layer. In alternative communication cases, the configuration information/parameters may be sent to the WTRU by the network (per a V2X Control Function) upon request from the WTRU. The WTRU may transmit a request message to the V2X Control Function before communication initiated or during the V2X communication.

In a V2X communication system, certain V2X messages may receive priority handling. Under 3GPP ProSe, ProSe Per Packet Priority (PPPP) may be defined such that the application layer assigns 8 different priority levels to every packet sent from the application layer in the WTRU to the Access Stratum layer. The Access Stratum layer may then queue/transmit the packets within the WTRU based on the received priority level or PPPP from the upper layers. V2X messages may be prioritized based on message type, such as safety messages prioritized over non-safety messages. V2X messages may also be based on the type of WTRU that is sending the message (e.g., ambulance, patrol car and the like). Priority handling procedures may be required for V2X communication over the Uu interface because current PPPP mechanisms only apply to PC5 communication (direct WTRU to WTRU communication) but in the case of V2X, per message priority may be applicable to Uu (LTE radio) transmissions, such as when safety messages have to be prioritized over non-safety messages.

As used herein, the application layer may include other higher layers, including but not limited to one or more of a V2X facilitation layer, a V2X messaging layer (used by, for example, signal phase and timing (SPAT) and other V2X protocols), and/or a Transport layer (used by, for example, a protocol such as wireless access for vehicular environment (WAVE) short message protocol (WSMP)).

The application layers or higher layers may provide some indication of the priority of the V2X message to the lower layers or 3GPP protocol stack (for example, a V2X layer, a ProSe protocol layer or an Access Stratum layer) similar to the per packet priority concept. The application level priority may be used as an input by the 3GPP protocol to determine the final message priority for the PC5 link or the Uu link. The application level priority may be used in one or more of the following ways.

In one example, the per message priority indicated by the application layer may be directly mapped to the 3GPP priority, such as the PPPP or logical channel ID based on the mapping rules received in the configuration information. Also, the ProSe protocol layer or V2X protocol layer may check the authorization information/configuration information to get the WTRU status/type (e.g., whether the WTRU is an RSU or whether the WTRU is an ambulance or a police patrol car). Based on this authorization check, the application level priority received from the upper layers may be upgraded or downgraded by the V2X (ProSe) protocol layer. For example, if the application level sends a PPP value of 4 for a particular message, the priority of this message may be upgraded to a PPP value of 2 if the authorization check indicates that the WTRU type is a police patrol car. The ProSe protocol layer and the V2X protocol layer are example protocol layers which may implement the described functionality; however, such functionality may also be implemented in other 3GPP layers, e.g., the Access Stratum.

For WTRUs in coverage, the priority of various V2X messages, particularly safety messages, may be determined using assistance from the eNode-B/MME insofar as the network may provide priority levels for specific safety messages via system information block (SIB) broadcast by the eNode-B. Alternatively, the priority levels may be provided via the V3 (PC3) interface as part of configuration information (as described elsewhere herein) or as a direct V3 control message exchange between the V2X WTRU and the V2X Control Function. The determination of the final priority may be based on a combination of application level priority and priority levels provided by the network. Alternatively, the network may inform a WTRU whether network based priority levels should be employed rather than priority levels received from the application layer. In such a case, the WTRU may ignore the application level priority and transmit messages based on priority levels received from the network.

In one example, the relay WTRU may be an L3 router meaning that the relay WTRU may not be aware of the contents of the V2X message or the type of the V2X message. The relay WTRU may therefore need a mechanism to forward the message to other WTRUs and/or the network with the appropriate priority. The relay WTRU may use a ProSe priority PPP to QCI mapping mechanism to transmit the message to the network in the uplink direction over the Uu interface. In one instance, the relay WTRU may determine priority when the message is relayed to other WTRUs. In another instance, a priority determination mechanism as defined elsewhere herein may also be applicable to a relay WTRU.

One method to facilitate the relay WTRU in determining the priority of the V2X message may be to include the Message type information included in the header of the V2X message. The message type information may consist of a few bits representing the category of the message. Some of the categories may include various safety messages (e.g., accident broadcast, road blockade and the like) and other categories may include traffic status messages. Message type fields may also be used for non-safety messages. Infotainment services may be an example that fits the criteria of non-safety messages. The initiating WTRU may include such type information in the header of the message. Upon receiving the V2X message, the relay WTRU may look for message type information to determine the priority to forward this message accordingly. The priority may be determined by a simple mapping of the message to a priority level or in combination with other parameters which are described elsewhere herein. The message header as discussed herein may be the IP header, packet data convergence protocol (PDCP), radio link control (RLC) or medium access control (MAC) header.

An initiating WTRU may also include the WTRU type or similar information in the header of the V2X message for priority reasons. As mentioned earlier, the WTRU type information may describe certain properties of the WTRU which is transmitting or broadcasting the V2X message. Police patrol car, fire engine, safety officer and the like are some of the examples of WTRU types which may be included in the V2X message header that have some priority. The WTRU type information may be preconfigured in the WTRU or the initiating WTRU may receive this information from the application layer/server or the V2X control layer/ProSe layer in the WTRU. When the relay WTRU receives the V2X message, it may look for the WTRU type field in the header of the message to be able use it as an input to decide on the priority for forwarding of the message. The WTRU type information may be either directly mapped to the priority level of the V2X message or may be used in conjunction with other parameters such as message type to determine the priority with which the message may be relayed by the relay WTRU.

The relay WTRU may also be able to determine the message priority from the L2 address or IP address used for PC5 communication. If such a procedure is employed, a relay may have certain configured information usable to map the broadcast address used for PC5 communication to a certain priority level. Such information may be in the form of message type or WTRU type. In other words, certain broadcast addresses may be used for particular messages or specific WTRU types by the initiating WTRU. Looking for such broadcast addresses in the PC5 message, the relay WTRU may be able to glean either the message type, WTRU type, or both. Alternatively, there may be a direct mapping between the broadcast address and priority level that may be configured at the relay WTRU.

V2X communication may use per message priority over the Uu interface. The characteristics of a V2X system requires that every message transmitted may have a different priority due to the various urgency levels of different messages. Traffic broadcast messages may have lower priority compared to safety messages as an example. Even within the category of safety messages there may be variable priorities depending on the nature of a message or the situation/incident that results in the transmission of a V2X message.

Per packet priority or per message priority may also be applicable to an entire V2X system, including message transmission over the Uu interface (e.g., the direct air interface between the WTRU and the eNode-B). As discussed herein, there may be a mechanism for exchange of a PPP or PMP between a V2X Application Server and the V2X WTRU. Such priority may be applied by the V2X WTRU for messages transmitted over the Uu interface. Applying these concepts to the example ofFIG.6, a mechanism may be used for the LGW/eNB system to receive the PMP to be applied by any one of the nodes as shown inFIG.6in the downlink direction (from the V2X Application server601to the WTRUs607aor607b). The V2X Application Server601may send a PMP or PPP to the LGW602via the SGi interface to be applied for the messages in the downlink direction. In case of a MBMS architecture for multicast/broadcast transmission of V2X messages, the V2X Application Server601may send the PPP or PMP over a MB2 interface. Once the LGW602receives a message with a particular PPP level, it may forward the message with the PPP/PMP or priority level to the eNB606over the S1-U interface. The eNB606may then use the PMP or PPP to schedule the messages in such a way that messages with higher priority are sent first to the WTRU607aor607bin the downlink direction over the LTE-Uu interface. While an example was provided applying the priority mechanism to the example architecture ofFIG.6, the priority mechanism may be applied to any architecture, including other architectures as discussed herein.

For PPP to be applied in the UL direction, the V2X application in the WTRU may receive priority levels for every message from the V2X Application Server. The application layer in the WTRU may pass the PPP along with the message to the access stratum or the lower layers. The lower layers may schedule the message over the Uu interface according to the received PPP value from the upper layers. Note that a PPP/PMP value received by the lower layer for Uu transmission may be different than a parameter used for PC5 transmission. This may enable the WTRU to differentiate whether the received PPP is to be applied to the corresponding Uu or PC5 transmission.

A similar transfer of priority level, as compared to the V2X priority message example processes based on the L-GW architecture discussed herein, may be applied to the MBMS architecture in the downlink (DL) direction.

In the alternative, a PPP value or a range of PPP values may be included in the policy control and charging (PCC) messages sent from the policy control and charging rules function (PCRF) to the GW during the setup of a selective IP traffic offload (SIPTO) PDN connection between the WTRU and the LGW or during the update of a SIPTO PDN connection. The LGW may apply these PPP values in the downlink direction as described elsewhere herein.

The WTRU may also receive PPP values during the setup or update of the connection for the uplink (UL) transmission. The MME may send the PPP value(s) to the WTRU in the non-access stratum (NAS) message. Further, the MME may receive these PPP values from the L-GW/S-GW over the S-11 interface.

In a V2X communication system, the transmission and/or reception of V2X messages may be made between two WTRUs such as a vehicle and a RSU. For example, a V2X message may be transmitted from a vehicle to an RSU, where the vehicle has a WTRU. An RSU can transmit a V2X message to a vehicle or distribute a V2X message to multiple vehicles. In some scenarios, the V2X message may be forwarded from an RSU to other RSU(s). To support V2X message transmission/reception between a vehicle and an RSU for V2X, processes must be made to enable vehicles to determine that a message needs to be sent to a RSU instead of another vehicle/pedestrian. From an RSU's perspective, the process can either forward the message to a vehicle, another RSU, or a V2X Application Server. In such cases, procedures have to be outlined for an RSU to be able to make the appropriate forwarding decision. Furthermore, the vehicle may either send unicast or broadcast messages to the RSU and then the RSU may either send a unicast message to the same or a different vehicle or send a broadcast message to different WTRUs. In one scenario, the addressing scheme for various unicast/broadcast communication to/from the vehicle or to/from the RSU may be addressed herein so that messages can be sent to or received by the intended recipients in a V2X communication system. Any reference to vehicle in the above discussion could also be a WTRU embodied in another form factor/use such as pedestrian.

A V2X message for vehicle to infrastructure (V2I) service(s) may be transmitted from a vehicle to an RSU. An RSU may also transmit a V2X message for V2I service(s) to a vehicle or distribute a V2X message for V2I service(s) to other vehicles. In some of these cases, the V2X message may be forwarded from an RSU to other RSU(s).

FIG.8is a system diagram of an example RSU communication scenario. In this example a WTRU may be a vehicle, a pedestrian, or other non-RSU embodiments. Looking atFIG.8there may be two scenarios: 1) communication804between one or more WTRUs801and an RSU1802, and 2) communication805between the RSU1802and other RSU(s)803. In either scenario the communication may either be PC5 communication or Uu communication in unicast, multicast, or broadcast form.

Communication with a RSU may happen via the PC5 interface, such as shown in inFIG.4. Also, such communication may be unicast, multicast, or broadcast depending on the application or the communication scenario. A signal phase and timing (SPAT) application, for example, may use unicast communication between the vehicle and the RSU, whereas a traffic status application or protocol may use broadcast communication from the RSU to the WTRU.

For any V2X communication scenario, PC5 messages may need to be sent to a particular destination with an L2 address and/or a particular IP address. The L2 destination address may be included in the PDCP header. These addresses may be assigned to the WTRU at a configuration stage or upon request from the WTRU-type RSU over the V3 interface between the RSU WTRU and the V2X Control Function. The procedures described herein may assume that a WTRU-type RSU has been assigned or preconfigured an L2 address and/or/IP address and/or Application Server, which may be there after referred to as an RSU address. The procedures may also assume that a V2X Control Function is cognizant of the RSU address in certain scenarios.

The example procedures described herein may be executed when the WTRU, such as a vehicle, enters a new area (such as, for example, a new geographic area) and may contact or receive messages from the RSUs in that area. The procedures may also be executed when the vehicle changes its public land mobile network (PLMN) and the vehicle does not have the authorization to access RSUs in that PLMN or the vehicle does not have the address of the RSU in the new PLMN. Interaction between a home PLMN (HPLMN) V2X and visited (VPLMN) V2X may occur in these examples, that is, in the case of the inter-PLMN RSU address procedure.

The V1 interface between the application client in a V2X WTRU and the V2X Application Server may be used to request the RSU address in a particular geographic region or for a specific V2X service. Upon receiving the request from the WTRU, the V2X Application Server may contact the V2X Control Function responsible for the location that the WTRU is in or the PLMN that the WTRU is camped on. The respective V2X control may in turn send the RSU address or prefix(es) to the V2X Application Server over the V2 interface after optionally performing the authorization check with the home subscriber server (HSS). The V2X Application Server may then forward the RSU address to the V2X WTRU.

FIG.9is a diagram of an example V1 procedure to acquire an RSU address. At905the V2X WTRU901may send an application level message to the V2X Application Server904over a V1 interface to request an RSU address. The message may contain one or more of: an application ID, a WTRU ID, an application type, a V2X protocol type (e.g., SPAT), information about a geographic area the WTRU901is located in, the PLMN the WTRU is camped on, an indication about a home operator, and other related information.

At906, based on the received information from the V2X WTRU901, the V2X Application Server904may decide which V2X function to contact to get an RSU address. This determination may be based on the WTRU's location, the service the WTRU is trying to access, the WTRU's home PLMN or the PLMN the WTRU is registered in.

At907the V2X Application Server904may send the RSU address request to the V2X Control Function903to retrieve the RSU address the WTRU901is interested in. This RSU address request may be a V2 interface message which may contain WTRU ID, information about the application (e.g., App ID), WTRU location information and the like.

At908, the V2X Control Function903may perform an authorization check with the HSS902to confirm if the WTRU901is allowed to connect to a particular RSU. An Authorization Request (which may include WTRU ID, request type (RSU address request), App ID etc.) message may be sent to the HSS902by the V2X Control Function903.

At910, the HSS902may check if the WTRU901is allowed to communicate with the RSU and/or the HSS902may check if the WTRU901is allowed to access the requested service. At910, the HSS902may respond back to the V2X Control Function903with an Authorization Response message.

If the request is authorized by the HSS902, the V2X Control Function903may then determine at911the RSU which can meet the required parameters received by the V2X Control Function903at907. At912, the V2X Control Function903may respond to the V2X Application Server204with an RSU address response message which may include the required RSU address. The RSU address may then be sent to the WTRU901in a V1 interface response message at913by the V2X Application Server904.

In an alternative scenario, the process described with relation toFIG.9may differ by performing fewer or additional actions. For example, a V2X Control Function may decide not to perform authorization with an HSS. Once the V2X WTRU receives the RSU address, this address may be used by the WTRU as a destination address in a PC5 message for a particular RSU.

In another alternative, when a WTRU receives the source address of a RSU, the V2X WTRU may filter out all the received PC5 broadcast messages based on the received source RSU address. The WTRU may only pass on the PC5 message to the upper layers whose source address matches the RSU source address as previously received.

In another alternative, a WTRU may request an RSU address from a V2X Control Function over a V3 interface. Upon receiving the request from the WTRU, the V2X Control Function may contact the V2X Application Server based on the information in the received V3 interface message from the WTRU. The V2X Application Server may then inform the V2X Control Function if the V2X WTRU is allowed to access the particular service or RSU providing that provides that service. If this check is successful then the V2X control may send the RSU address or address prefix(es) to the V2X WTRU over the V3 interface. The V2X Control Function may also optionally perform the authorization check with the HSS during this procedure.

FIG.10is a diagram of an example V3 procedure to acquire an RSU address. At1005the V2X WTRU1001may send a V3 interface message to the V2X Control Function1003to request an RSU address. The message may contain one or more of: an application ID, a WTRU ID, an application type, a V2X protocol type (e.g., SPAT), information about a geographic area the WTRU is located in, the PLMN the WTRU is camped on, an indication about a home operator, and the like.

At1006, upon receiving the RSU request from the V2X WTRU1001, the V2X Control Function1003may determine which V2X Application Server is responsible for providing the required V2X service. At1007, the V2X Control Function1003may send a V2 interface message to the V2X Application Server to check if the WTRU1001is authorized to use that application or access the RSU which provides that service. This message may include WTRU ID and/or location information about the V2X WTRU1001.

At1008the V2X Application Server may perform the authorization check based on the parameters received at1007. At1009, the V2X Application Server may respond with an Authorization response message.

The HSS authorization part at1010of this procedure between the V2X Control Function1003and the HSS1002may be similar to that shown in the example ofFIG.9. If the authorization(s) is successful, the V2X Control Function1003may retrieve the RSU address(es) or prefix(es) at1011. At1012the V2X Control Function103may send the RSU address(es)/prefix(es) in the RSU address response message over the V3 interface to the WTRU1001.

In an alternative, if a V2X Control Function does not have the local Application Server address, it may contact the V2X Application Server in macro network to request the address of the local Application Server. For such a retrieval process the V2X Control Function may send the geographic area information/location information of the local area whose local V2X Application Server the V2X WTRU is requesting the address for.

In another alternative, the process described with relation toFIG.10may differ by performing fewer or additional actions. For example, a V2X Control Function may decide not to perform authorization with an HSS. Once the V2X WTRU receives the RSU address, this address may be used by the WTRU as a destination address in a PC5 message for a particular RSU.

In another alternative, a WTRU may receive the source address of the RSU. In that case, the V2X WTRU may filter out all the received PC5 broadcast messages based on the received source RSU address. The WTRU may only pass on the PC5 message to the upper layers whose source address matches the RSU source address received previously.

In certain emergency situations, low latency or out of coverage scenarios, certain RSU addresses may be provided to a WTRU as part of a configuration. These addresses may be source addresses, destination addresses, or both. For such emergency or safety applications, the WTRU may perform procedures different than those described inFIG.10or9. The WTRU may just use the configured RSU address to send the PC5 message or the configured source address may be used to filter out the PC5 message which may be broadcasted by various RSUs in the vicinity of the V2X WTRU. When the V2X WTRU broadcasts a PC5 message, any RSU receiving the message may be able to infer that the broadcasted message is an emergency message based on the characteristics of the address. The emergency address may be a special address known to RSUs. Therefore, the RSU may be able to take the appropriate action upon receiving the message with an emergency destination address. For example, the RSU may rebroadcast the message with high priority and/or forward the message to the V2X Application Server. Similarly, the V2X WTRU may also be able to receive a PC5 message with the emergency address.

The eNB type RSU as illustrated inFIG.5consists of an eNB with a LGW that may interface with a V2X application. To be able to connect to the V2X application via eNB type RSU, the WTRU may need to have a SIPTO connection with the LGW. Therefore, in one example, similar procedures as described inFIG.9andFIG.10may be used by the V2X WTRU to retrieve the APN to be used for a SIPTO PDN connection with eNB RSUs. The RSU address may be sent to the WTRU by either a V2X Application Server or a V2X Control Function because the eNB type RSU address may be an APN for the SIPTO PDN connection. Such an APN provision by the V2X Control Function or the V2X Application Server may be applicable to both RSUs operating in normal E-UTRAN mode or operating in isolated E-UTRAN mode with a local EPC.

When the WTRU receives an APN in the RSU address response message, it may know that it needs to connect to an eNB type RSU and, therefore, may send a PDN connection request which includes the received APN. The WTRU thus may be able to create a PDN connection with the RSU and may be able sent a V2X message to that RSU via the SIPTO PDN connection.

In on example, an eNode-B type RSUs may broadcast the services they provide and possibly APNs corresponding to those services in the SIB messages. The V2X WTRU may read those SIBs and request connection with the RSUs the V2X WTRU is interested in.

FIG.5may be used to demonstrate one specific example of an eNB based on the SIPTO LGW architecture. There may however be other possible implementations for eNB type RSUs. One such implementation may be based on eMBMS or local eMBMS architecture.

FIG.11is a system diagram of an example of an eNB type RSU supporting local MBMS.FIG.11shows an example eNB type RSU1102including a MBMS-GW1105, a BM-SC1104and a V2X Application Server1107. The MBMS-GW1105and the BM-SC1104may either be collocated with the eNB1106or standalone nodes. A WTRU A1103, such as a vehicle, may run an instance of a V2X Application1101. The WTRU A1103may communicate with the RSU1102.

For an eNB type RSU, the RSU address may be a TMGI or Service area ID which may be sent to the V2X WTRU as described by the procedures above herein. The V2X WTRU may then look for the specific TMGI corresponding to the V2X service it may be interested in.

In one embodiment, the uplink messages may need to be addressed to a particular RSU and the WTRU may need to obtain the RSU address for the transmission of uplink messages. The USD (User Service Description) information received by the WTRU for receiving downlink messages may also contain information about the uplink RSU address. Such USD information may be sent to the WTRU via short message service (SMS), SIB broadcast, or MBMS broadcast (such as a service announcement over a global or well-known TMGI) used for disseminating MBMS configuration information for specific MBMS or V2X services.

FIG.12is a diagram of an example procedure using options for acquiring an eNB based RSU address. In the example shown inFIG.12, the WTRU1201may obtain the RSU address or V2X Application Server address from one of the three illustrated options1205a,1205b, and1205cshown. For1205a, USD information received via SMS, wireless application protocol (WAP), or hypertext markup language (HTML) push messages and the like may include the RSU server address/V2X Application Server1204address. For1205b, the V2X WTRU1201may be configured with the well-known TMGI used to monitor service announcement messages for various V2X services from the MBMS-GW/BMSC1203; such a service announcement may also include information about the uplink RSU address/V2X Application Server address. For1205c, the SIB broadcast may include the RSU address/V2X Application Server address from the eNB1202.

After receiving the address, the WTRU1201may include the received address in the uplink V2X message at1206. At1207, the uplink V2X messages may get routed to the appropriate V2X Application Server1204based on the RSU address.

In one embodiment relating to a V2X communication system, there may be a geographic scope for a V2X message given that in at least one scenario a message may only relate to a specific geographic area. When the V2X WTRU, RSU or eNB transmits a message, it may only be applicable to a certain location. For instance, an accident report message may only be relevant in the vicinity of the area where the accident took place. If an accident took place, the V2X messages may be localized to a certain geographic scope relating to the accident. In another example, information about a traffic jam at location X may not need to be broadcasted at location Y. In yet another example, a distressed vehicle may only need to send out an SOS type message only in its surrounding location.

The system therefore may need to provide mechanisms for a V2X WTRU or RSU to be able to restrict the transmission or rebroadcast of certain messages to a particular geographic area. Further to this requirement, the geographic area may be of varying size such that that dissemination of the message to a particular area size may depend on the type of the message or even the contents of the message. V2X messages may be rebroadcast by various nodes in the V2X system, for example, V2X vehicles, V2X infrastructure, V2X RSUs, V2X pedestrians, and the like. However, this rebroadcast of messages may be restricted to a geographic area.

FIG.13is a diagram of an example procedure for restricting a message in a geographic location. At1301a V2X WTRU may receive a V2X broadcast message with a geographic scope. The received message header may contain a broadcast number. Every time the message is rebroadcast, a node that rebroadcasts the message may include the broadcast number e.g.,1in the message header. At1302the receiver of the message may check the broadcast number in the message header. At1303, the message is passed to the App layer and if the message header is greater than 0, the message may be broadcast again subtracting 1 from the number in the message header. At1304when the broadcast number is less than 0, the WTRU may just pass the message to the V2X application in the WTRU and not re-broadcast the message thereby confining the number of times the message is re-broadcast based on the number of times it has been received and re-broadcast.

The broadcast number may be configured at the WTRU during the initial V2X configuration or may be sent with to the WTRU during V2X RSU address procedure along with the RSU address as described earlier in this section. In an example, the broadcast number may be provided by the V2X Application Server or application layer in the WTRU as the application may be aware of the location and, therefore, may have enough information to decide how far the message should be broadcast.

In one example, a local eMBMS server may have certain MBMS functionality, such as userplane functionality, reside closer to the eNB or RAN node; these functions may be known as an LME and such a configuration may be seen inFIG.7as discussed herein. The V2X Application Server may need to send the DL MBMS messages to the LMEs for which the geographic scope of the message is intended. In such a scenario, the V2X Application Server may send the list of MBMS Service area IDs/cell IDs to the BM-SC for the service areas for which the downlink V2X message is intended; this case may be based on the assumption that the V2X Application Server is configured with either a list of cell IDs or MBMS Service Area IDs (SAIs). The BM-SC may then select one or more LMEs based on the received cell IDs or MBMS SAIs.

FIG.14is a diagram of an example procedure for selecting one or more LMEs based on received cell IDs or MBMS SAIs. At1407the V2X Application Server1403may be configured with Cell IDs or MBMS SAIs and possibly mapping between the V2X geographic area and SAIs/Cell IDs. At1408the V2X Application Server1403may send a TMGI allocation request message to the BM-SC1406, which includes the SAIs of the area where the V2X Application Server1403is interested in broadcasting the message. At1409, based on the received MBMS SAIs, the BM-SC1406may send the information about the LME1402that serves the area of interest to the V2X Application Server1403. The LME information may be the IP address of the LME, LME Identifier, and the like. The V2X Sever1403may be preconfigured with LME information (e.g. FQDN or IP address for the LME). When there is a need to establish delivery path for V2X message, the V2X Server1403initiates at1410Local Distribution Request procedure with the LME1402. This message may include TMGI as an identifier. At1411the LME1402may reply with the Local Distribution Response message including the IP address/port in LME for receiving the data, and the associated information of Local MBMS Distribution, e.g., IP Source Address, and IP Multicast Address in LME for IP multicast distribution. In LME, there may be a1:1mapping between the IP address/port for receiving the data, and the associated IP source address/IP Multicast address. At1412the V2X Server1403may initiate Activation MBMS Bearer Request procedure, where the message of the procedure may include information of Local MBMS Distribution (IP Multicast address). At1413the BM-SC may initiate MBMS Session Start procedure where upon the reception of the information of Local MBMS Distribution the MME/MBMS-GW1405may skip the normal processing for IP multicast distribution, e.g. allocate an IP multicast address. At1414the MBMS Session Start Request message is sent from the MME/MBMS-GW1405to MME (not shown) where it is forwarded to the eNB/MCE1401. At1415the eNB1402joins the IP Multicast group in the LME1402. Now Thereafter the LME1402may send V2X Data via the IP/port address received previously.

In another example, when the BM-SC receives the MBMS SAIs in a TMGI monitoring request message or a similar message, it may include the preference for local eMBMs. The BM-SC may then retrieve the LME info based on receiving the BM-SC and directly trigger the local LME to start the MBMS session.

In a system for V2X communication, V2X messages containing data may be sent over the control plane. Specifically, in one example, V2X data may be sent over PC5 signaling (PC5-S) (a PC5 control plane in the case of PC5 communication). In another example, for the case of a Uu interface, the V2X data may be sent over a Signaling Radio Bearer (SRB), e.g., in a radio resource control (RRC) message to the eNB.

PC5-S messages may be exchanged between the ProSe Protocol Layers (V2X Control Layers) of the WTRUs. The V2X application may interface with the ProSe protocol layer or V2X layer in the WTRU to send V2X messages over the PC5-S. The ProSe protocol layer may include certain information in the header of the PC5-S message to indicate that the message contains data or particularly the type V2X data (SPAT, WSMP, and the like). At the PDCP layer of the transmitting WTRU, the SDU may be labeled or the PC5-S codepoint for the SDU may be used. PC5-S messages passed down to the lower layer in the transmitting WTRU may have an associated priority based on the priority determination procedures described herein. Alternatively, such a PC5-S message (which may contain V2X data) may always receive the highest priority treatment by the lower layers in the WTRU.

At the receiver side, the PDCP may then check a code point and infer that it has received a PC5-S message. The message may therefore be passed onto the ProSe protocol layer (V2X Control Function). Upon examination of the PC-5 message at the ProSe Protocol layer it may be determined (based on the PC5-S header) that the message contains V2X data. The data part of the message may then be forwarded to the appropriate V2X application. For such steps to happen, additional information about the type of V2X application, application Id or V2X may be included in the PC5-S message.

V2X messages (both IP and non-IP) may also be sent over the Uu control plane while performing V2X services over the LTE air interface. The V2X application layer or facilitation layer may send the message directly to the access stratum, e.g., RRC or PDCP in the V2X WTRU. A new information element (IE) may be defined for the RRC message to indicate that the RRC message contains V2X data or special code point in the PDCP defined for such purpose.

When the eNode-B receives the RRC message with an indication that it contains V2X data or gleans from a PDCP header code point that a V2X data payload is contained in the message, it may not forward the control message to the MME via the S1-AP interface (which is the normal behavior). Instead the eNode-B may extract the V2X data from the control message and send it to the V2X Application Server either directly or via the LGW. As described earlier herein, the message may contain additional information about the application to assist the eNode-B to direct the message to the appropriate V2X AS.

In the DL direction, similar actions may be performed by the transmitting eNode-B and the receiving WTRU. The difference may be that eNode-B may receive the data directly from the Application Server, LGW or MBMS GW.

Although features and elements are described above in particular combinations, one of ordinary skill in the art will appreciate that each feature or element can be used alone or in any combination with the other features and elements. In addition, the methods described herein may be implemented in a computer program, software, or firmware incorporated in a computer-readable medium for execution by a computer or processor. Examples of computer-readable media include electronic signals (transmitted over wired or wireless connections) and computer-readable storage media. Examples of computer-readable storage media include, but are not limited to, a read only memory (ROM), a random access memory (RAM), a register, cache memory, semiconductor memory devices, magnetic media such as internal hard disks and removable disks, magneto-optical media, and optical media such as CD-ROM disks, and digital versatile disks (DVDs). A processor in association with software may be used to implement a radio frequency transceiver for use in a WTRU, UE, terminal, base station, RNC, or any host computer.