ITS Standardization Oyunchimeg Shagdar, Inria Thierry Ernst, Mines Paris Tech JNCT: Les Journées Nationales des Communication dans les Transports 29 Mai 2013
ITS: Intelligent Transportations Systems Systems in which information and communication technologies are applied in the field of road transport, including infrastructure, vehicles and users, and in traffic management and mobility management, as well as for interfaces with other modes of transport. EU Directive 2010/40/EU Overview of the talk ITS applications ITS standards in USA, Europe, and Japan Cooperative ITS Harmonization of ITS Standards 2
ITS Applications Cooperative ITS: Application Road safety applications Traffic efficiency applications Infotainment applications Cooperative ITS: Application Diversity Ernst Cooperative ITS April 2013 2 Ernst Cooperative ITS April 2013 3
ITS applications (cont ) 4
ITS Standards are to enable interoperability by specifying Who communicate with whom (vehicle, pedestrian, road-side infrastructure, central servers) Using what type of message Which media (wireless frequency band) and which protocol (MAC/IP/..) For which application? 5
ITS standards developing organizations (SDO) Regularity constraints (e.g., radio frequency) are different depending on the country/region. Standardization activities USA: IEEE, SAE (Society of Automotive Engineers) ping Organisations Japan: ITS Info-Communications Forum, ARIB (Association for radio industry and business), ISO ds Developing Organisations Europe: CEN (European committee for standardization), ETSI (European telecommunications standards Institute), NewISO TC starting ITS Standards Developing Organisations ITS Standards Developing ISO TC204: ITS (1993) New TC starting IEEE 802.11p IEEE P1609 TC ITS (2007) ng and partly CEN TC278: J2735 RTTT (1992)J2945 IEEE 802.11p IEEE P1609 competing ITS Standards Developing Organisatio TC ITS (2007) J2735 J2945 IEEE 802.11p IEEE P1609 J2735 New TCJ2945 starting ISO TC204: ITS (1993) New TC starting ISO TC204: ITS Challenge: SDOs and RTTT partly competing CEN TC278: (1993)are overlapping are overlapping and partly competing TC ITS (2007) Proliferation of standards(1992) n of standards 6 CEN TC278: RTTT TC ITS (2007) IEEE 802.11p IEEE IEE J27
Radio spectrum dedicated to ITS Communications Frequency (MHz) 500 1,000 5,800 5,900 ITU-R 5,725 5,875 Europe 5,795 5,875 5,905 5,815 5,855 5,925 North America 902 5,850 5,925 928 Japan 700 MHz Band 5,770 5,850 10 MHz expected in this band In use Allocated Potential 7
ITS Standards in USA IEEE WAVE 8
IEEE and SAE standards (USA) Safety applications Non Safety applications Safety application sublayer Application SAE J2735 IEEE 1609.3 Message sublayer WSMP 1609.2 Security Transport (TCP/UDP) Network (IPv6) IETF RFC 793/768 IETF RFC 2460 IEEE 802.2 IEEE 1609.4 IEEE 802.11p LLC sublayer MAC sublayer extension MAC sublayer PHY layer 9
WAVE: Application to Middle layers SAE J2735: Defines message sets, message formats for especially safety applications IEEE 1609.3 WSMP (WAVE short message protocol) for safety application Reduced overhead: WSMP has 11 bytes of overhead Allows applications directly control lower-layer parameters 10
WAVE: MAC/PHY IEEE 802.11p PHY: IEEE 802.11a: OFDM (3 to 27 Mbps) at 5.9 GHz MAC: IEEE 802.11e (CSMA/CA) for QoS, No access point functionality IEEE 1609.4 Multichannel operation: CCHs Time-division channel coordination 100 ms 100 ms 100 ms SCH SCH SCH CCH SCH SCH SCH 5.855 5.865 5.875 5.885 5.895 5.905 5.915 5.925 Spectrum (GHz) Guard interval CCH interval 50 ms Guard interval SCH interval 50 ms Guard interval CCH interval 50 ms Guard interval SCH interval 50 ms Guard interval CCH interval Guard interval SCH interval 50 ms 50 ms time 11
ITS Standards in Japan ARIB 12
Support multi-types of applications by DSRC Main concern: safety applications Fast (single/multi hop) message dissemination Allows internet applications. DSRC protocol stack No presentation/session/transport/network layers Application Sub Layer (ASL) For various types of, IP-based, Non-IP-based applications Application layer (L7) Presentation layer (L6) Session layer (L5) Transport layer (L4) Network layer (L3) Data link layer (L2) Physical layer (L1) 13
ITS communications media and Access Control 80% of traffic accidents in Japan occur at intersections DSRC over 5.8GHz band, CSMA/CA, Considering the compatibility with IEEE 802.11p Use of 700 MHz Compared to 5.8GHz, 700 MHz has larger coverage and bends well fits better to Intersection scenarios Design of V2V and R2V Time division access [ Types of traffic accidents] [ Collisions with pedestrians Rear-end collisions Other 32% 9% 14% 26% Collisions with cross traffic at intersections V2V and R2V communications zone V2V communications zone Right-turn or left-turn collisions R2V interval R2V interval Time 14
System architecture advanced ITS radiocommunications in Japan. APP1 APP2 APP3 APP4 System Management SME _SAP IVRLME _SAP MLMEX _SAP MLME _SAP PLME _SAP IVC-RVC Management Entity (IVRLME) MLME Extension MAC Sub-layer Management Entity (MLME) PHY Sub-layer Management Entity (PLME) SME _SAP L7:Application Layer IVRI_SAP IVC-RVC Integrated Access Control Information LLC_SAP LLC Sub Layer MAC_SAP MAC Sub Layer IVC-RVC Integrated Access Control PHY_SAP PHY SEC _SAP IP extension (TCP/IP UDP/IP) LLC_SAP SEC _SAP SEC _SAP Security Management 9 15
ITS Standards in Europe ETSI 16
ETSI TC ITS (Europe) A new layer: facilities layer Geonetworking in Networking & Transport Layer 17
ETSI -- Applications Basic set of applications Road safety Emergency vehicle, slow vehicle, wrong way driving, etc. Traffic efficiency Speed limits notifications, enhanced route guidance Management Applications Facilities Network &Transport Access Technologies Security 18
Facilities (Application Support) ITS stations (vehicle, roadside, central, personal) exchange information used by several applications Managed in the facilities layer CAM (Cooperate awareness message): status information of ITS stations, e.g., position, speed, moving direction DENM (Decentralized Environmental Notification Message): information of road traffic event, e.g., traffic accident, road work, traffic jam Management Applications CAM Facilities DENM Network &Transport Access Technologies Security 19
Facilities: LDM (Local Dynamic Map) 20
ETSI Network and Transport Geonetworking Information delivery to particular geographical destination area BTP UDP-like protocol for Geonetworking IP networking Information delivery using IP addresses UDP/TCP Transport Basic Transport Protocol Transmission Control Protocol User Datagram Protocol Geonetworking Internet Protocol (IPv4, IPv6) Network 21
GeoNetworking: Network layer message dessimination protocol Information dissemination to a particular geographical region. Geobroadcast: to all nodes in an area Geounicast: to a node Geomulticast: to a set of nodes GeoAnycast: to any node in an area Functionalities Building neighbor location table based on periodical beacons (or use CAMs) Geonetworking forwarding decision utilizing the neighbor location table MAC Header LLC Header GeoNetworking Header GeoNetworking Security Header (optional) Payload (optional) Common Header Extended Header Common header: 36 bytes. Contains geographical location of the sender (24 bytes). Extended header: depends on the dissemination type. GeoUnicast: 52 byes 22
IP networking Internet based and E2E service between ITS stations Maintaining information flow over any available media (11p, 11n, cellular, satellite, ) Inter-operability between various ITS and non-its sectors 23
Combination of IP and Geonetworking IP tunneling / IP over Geonetworking 24
ETSI Access technology (ITS-G5) Use of IEEE 802.11p (MAC/PHY)over the European spectrum ES 202 663 Decentralized Congestion Control TS 102 687 Motivation: Channel congestions can largely degrade communication performance Cross layer congestion control at Access layer (E.g., Transmit power/rate control) Network & Transport Facilities Management plays a central role 25
ITS New Paradigm: Cooperative ITS Harmonization activities - 26
Traditional ITS Often designed for a single use case / application (silo) Built in with a specific communication box/media Cooperative ITS ITS reference architecture (ISO/ ETSI) supporting diversity of ITS stations (vehicle, roadside, central, personal) Media (802.11p, 2G/3G, 802.11n) Applications (road safety, traffic efficiency, comfort) Communications protocols: Internet protocol (IPv6) and non-ip protocols Management Applications Facilities Networking & Transport Access Technologies... Security - 27
ITS Standards Harmonization (USA EU JP) -Summary- Protocol stack: ETSI/ISO ITS reference architecture Use of various media: Common understanding 5.8-5.9 GHz : CSMA/CA: Harmonized Channel coordination A number of CCHs and SCHs: USA and EU Switching between CH and SH: Only USA R2V and V2V Time division access: Only JP Congestion control Cross layer congestion control: Only EU (details are not clear) Non-IP and IP communications: Same consensus Large difference in handling Non-IP messages Geonetworking on Network layer: Only EU Use of IPv6 for Internet applications: common understanding, needs more effort 28
Thank you 29