Traffic Message Channel (TMC) is a technology that is used to transmit information about traffic jams and adverse traffic conditions. As a rule, data is transmitted in the form of digital codes, using the radio alert system (FM-RDS) for conventional FM receivers. Data can also be transmitted to radio or satellite radio . Road traffic data services are currently provided by state and commercial companies in most European countries. Support for TMC functions allows the car's navigation system to obtain information about areas with traffic incidents and to build an alternative route to bypass problem areas.
Principles of Operation
Data on each incident in traffic is transmitted as a TMC message. A message consists of an event code, a location code, and an event direction. Event codes are based on the Alert C standard ( ISO EN ISO 14819-6-2007 standard), which contains a list of 2048 events, the codes of these events can be transmitted to the TMC receiver in the user's language.
The source of traffic information, as a rule, are police services, security cameras on the roads , data from traffic control devices and others.
Location codes are supported at the state level, with each section of the road network assigned a unique code.
To create a national network, it is necessary to prepare TMC tables and certify them in the European non-governmental organization TISA (Traveler Information Services Association), which coordinates the implementation of TMC technologies and standards. After certification of tables in TISA, the organization that has applied for certification of tables, a certificate of compliance of the tables with TISA rules is issued, tables are assigned unique numbers, and data on them (location codes) are available to all members of this organization.
Organizations that are members of TISA who wish to use certified TMC tables in their navigation devices contact the organization that owns the certificate for the required table and receive permission to use. Navigation devices contain cartographic material, into which, after obtaining permission to use the TMC table, the necessary unique codes of this table are entered.
TISA members include major manufacturers of navigation systems and maps (including NAVTEQ and Tele Atlas ), car manufacturers, broadcasters, national traffic management services and many other companies. 
In April 2007, at a CanSecWest conference, two Italian hackers, Andrea Barisani and Daniele Bianco, demonstrated how to easily send false messages to navigation systems that receive traffic information via the FM channel. Their report on RDS-TMC was published , and detailed instructions and diagrams were posted in Phrack's hacker magazine (issue number 64). 
The fact that hackers are potentially able to emulate TMC messages and thus mislead drivers using navigation systems (or create problems for traffic) remains an urgent problem, since most of the European channels that transmit traffic information are not encrypted, but sent via TMC (although the TMC messages themselves can be encrypted) within the RDS channel. Currently, Transport Protocol Experts Group ( TPEG) technology is proposed as a replacement for TMC, but TPEG also lacks encryption, which does not completely solve the problem.
In the United States and Canada, the TMC security situation is much better, because the data is transmitted in encrypted form via satellite channels and through the DirectBand wireless data network, which also uses an FM band that is not occupied by radio stations for data transfer. The DirectBand network is built and managed by Microsoft , and operates in 125 cities in the United States and Canada.
Existing traffic information services
Intelematics Australia began providing RDS-TMC services in Australia's largest cities. These services are currently in the testing and debugging phase. Broadcasting is carried out by the national commercial FM radio company.
In Austria , ORF Broadcasting Company transmits data for free on 9 regional radio channels, this service is also supported by the Federal Ministry for Transport, Innovation and Technology of Austria (Federal Ministry for Traffic, Innovation and Technology (BMVIT)). Motorway and Motorway Financing Agency, Austria (ASFINAG) is responsible for setting location codes for the road network.
In Belgium, free TMC broadcasting is supported by three radio companies:
- VRT is a TIC-VL service on Radio 2, Flanders coverage, data provided by Verkeerscentrum Antwerpen.
- RTBF - CLASS.21 service on the Classic 21 channel, Walloon coverage, data provided by Center PEREX of the Ministere de l'Equipement et des Transports (MET) in collaboration with TMC4U.
- 4FM is a ViaTMC service from Vialis, which also supports TMC services in the Netherlands, Flanders coverage, data provided by Verkeerscentrum Antwerpen and PEREX and covers all regions of Belgium.
Commercial TMC services are planned to be provided by Be-Mobile, in collaboration with Proximus and Touring Mobilis.
Location codes ordered by a number of regional authorities were developed by Tritel.
Privately held iTIS Holdings provides commercial TMC iTMC services throughout England. Data is transmitted on the Classic FM channel. Service fees are charged when you purchase a car or when you purchase a navigation system. The service uses data collected from sensors installed on vehicles (Floating Vehicle Data system); about 50 thousand cars are involved in the system (Eddie Stobart haulage installed a system on 750 cars, The Automobile Association (AA Patrol) on 3800, National Express on 530).
RAC Live is supported by RAC Trafficmaster Telematics (RTT), a 50/50 joint venture of RAC Motoring Services and Trafficmaster. Broadcasting is provided on 3 commercial radio channels GWR, Capital radio and Chrysalis, which together cover the bulk of Britain. This service uses road infrastructure to measure speed, including sensors installed every few miles and equipped with a number recognition system.
Both services develop their own tables with location codes.
Free and commercial TMC services are available in Germany. Free TMC data is distributed by all publicly-owned television and radio companies and is available throughout the country.
The paid service TMCpro is provided by Navteq Services GmbH, a subsidiary of NAVTEQ (until 2009 T-Systems Traffic, a subsidiary of T-Systems ), since 2004 this service has been available throughout Germany. Data is provided by ddg Gesellschaft fur Verkehrsdaten mbh by a subsidiary of T-Systems Traffic GmbH, is encrypted in accordance with the TMC Forum specification, and the signal is distributed by private radio companies. One-time payment for using TMCpro is included in the initial cost of the navigation device.
The development of location codes for the country is carried out by BAST (German Federal Highway Research Institute).
The free DK-TMC service is provided by Vejdirektoratet or DRD (Danish Road Directorate), which is also responsible for developing location codes for the country. Radio station Danmarks Radio channels DR, P1, P2, P3, P4.
The TMC service is supported by Sam Road , an Iranian manufacturer of car navigation systems, a commercial company. Currently, the service is available only to Sam Road customers, however, the company plans to make this service publicly available until 2012.
A free TMC service is available on Radio Nacional de Espana. The service is provided by:
- SCT - Traffic Service in Catalonia
- DT at Basque Country Autonomous Community
- DGT (Traffic General Directorate) is a traffic service in other regions of the country.
The road network covers highways, national and first level roads. In addition, RACC is working on the creation of TMC services in major cities, planning to start with Seville and Barcelona. Broadcasting will be carried out on Radio Nacional de Espana (RNE 2).
Location codes are developed by DGT, Direccion General de Trafico.
Since July 1, 1998 free RDS-TMC services are provided by CCISS (National Traffic Information Center). Broadcasting on the RAI network on Radio 1. Coverage Northern Italy, from Turin to Venice.
Another TMC service is supported by the commercial RTL radio station in collaboration with InfoBlu, Broadcasting on RTL 102.5 radio stations. To use the service you need special software for the receiver. Coverage 90% of Italy.
Location codes are developed by RAI-CCISS.
TMC services are provided by TMC4U. Currently, these services are free, but it is planned to introduce paid services. Data is transmitted on the SkyRadio, Radio Veronica, Radio 1 and Radio 3 radio channels. The second ViaTMC service is provided by Vialis'. Data is transmitted on Q-music, BNR Nieuwsradio and Radio 538. The traffic jams, road works, etc. are identical in both services, but data from road speed radars are collected and provided independently.
Location codes are developed by AVV Transport Research Center.
Due to the transition to DAB, the DAB + radio system is no longer available from May 2017.
In Finland, the free TMC service is provided by Destia . Coverage area all major cities and roads (1999), i.e. service covers the whole country. TMC messages are transmitted by the national broadcaster YLE Radio Suomi .
Destia uses traffic camera data, special devices, and partner company data to collect traffic data. Transmitted data is encrypted based on specifications developed by TMC Forum.
France has free and commercial TMC services.
Free services are provided by toll road operators (AREA, ASF, ATMB, Cofiroute, ESCOTA, SANEF, SAPN, SAPRR, SFTRF and SMTPC). TMC data is broadcast on channel 107.7, and the coverage area is along toll motorways.
The paid V-Trafic service is provided by Mediamobile. This is a partnership between TDF , Renault , Trafficmaster and Cofiroute. Broadcasting on France Inter frequencies, covering the entire country (main motorways and Paris). Initially, the service was free, but now it has been paid. Although TMC data is not encrypted to restrict access, an alternative location code table is used. A similar method is recognized in the TMC Forum as "interim encryption". The service has about 60,000 customers.
The joint service ViaMichelin and Carte Blanche is broadcast on the Towercast network. In September 2005, PSA Peugeot Citroen signed a partnership agreement with ViaMichelin on the use of traffic data in its navigation systems.
The development of location codes for the country is carried out by the state agency SETRA (about 20,000 locations. SETRA also develops location codes for Andorra.
Since January 2006, 2 TMC services have been operating in the Czech Republic:
- DIC PRAHA service is available in Prague , broadcast on the Cesky Rozhlas radio station - Regina channel (92.6 MHz). Services are provided by TSK-PRAHA (Communication Technical Administration). Data - information about traffic incidents submitted by the Prague Traffic Center (TIC Praha).
- Joint Teleasist service and Global Assistance coverage area of the whole country, however, the data is less detailed than in DIC Praha. Radio station Cesky Rozhlas - CRo1 Radiozurnal.
The development of TMC services is coordinated by CEDA, which is also responsible for the development of country location codes.
The free TMC service is provided by the Swedish Road Administration (SRA or Vagverket), which is also responsible for the development of location codes.
Sweden is divided into 8 broadcasting zones, for data transmission only about local traffic. The coverage area of European, national and regional highways, TMC data includes information on traffic accidents, road works and weather. Broadcast on the Sveriges Radio network on SR P3.
The TMC service is provided by Viasuisse, and is broadcast by Swiss Broadcasting Corporation on FM chain 1.
The Swiss Federal Roads Authority FEDRO is responsible for developing the location codes, but they are being developed by B + S Ingenieur (Bundesamt fur Strassen).
USA and Canada
XM Satellite Radio and Sirius Satellite Radio broadcast TMC messages throughout the United States. TMC services also represent Clear Channel and Tele Atlas using FM-RDS in 77 US cities and 3 regions of Canada.
Microsoft supports its own DirectBand wireless network covering 125 cities in the USA and 3 cities of Canada, which also broadcasts TMC messages in the FM band. In September 2007, Microsoft released the MS Streets & Trips car navigation system, which combines three components — map software and two receivers: GPS and MSN Direct. The latter provides the user with information about road traffic and gas prices at each gas station he passes by. In addition, the novelty is integrated with the Live Search Maps directory, allowing travelers to get information about roadside infrastructure in any area of interest to them. The total number of objects included in Live Search Maps reaches 1.6 million, among them - ATMs, hotels, restaurants and various attractions. [four]
NAVTEQ, a global provider of digital maps for car navigation devices, bought Traffic.com in November 2006 (headquartered in Wayne, PA in 1998), which provides paid traffic information in 50 of the country's largest cities. Traffic.com is used by government and commercial organizations, various electronic media including AOL, Microsoft, The Weather Channel, Comcast, Garmin and XM Satellite Radio.
Plans for implementing TMC services in other regions
The introduction of TMC services is planned in Portugal and Hungary (test broadcasting is planned in the second half of 2008). In Ireland and Luxembourg, TMC services are not yet planned. In Poland, a private radio station made a test launch, but the Directorate for National Roads and Motorways GDDKIA has not yet decided on a full implementation. In Dubai, location codes are certified at the TMC Forum. In Turkey, the launch of the TMC service is only planned.
In China , studies are underway to select the technology on which the traffic information service will be based. The main applicants are the Japanese VICS system and the European TMC. However, the location code table is already certified by TMC Forum.
TMC in Russia
In Russia, there are several commercial services based on TMS.
On June 17, 2005, the Minister of Transport of the Russian Federation touched on the topic of processing data on traffic jams in navigation systems and stated that the state, represented by the Ministry of Transport of Russia and Roskartography, would actively work with private business to support “Russian navigation in all aspects”  . However, since then no activity of the Ministry of Transport in this area has been noticed.
The plans for participation in the creation of the TMC service in Russia were also announced by Navigation Charts, a Russian partner of TeleAtlas, a company that produces maps for full-time car navigation systems. 
On June 24, 2009 CJSC Navikom (the official supplier of Garmin in Russia) began broadcasting information on the speed of traffic on Moscow roads in the RDS-TMC format. This service is available only to users of Garmin Nuvi navigators with the letter "T" in the model name, for example, nuvi 2595LMT.  . Currently, traffic information is inaccurate due to the inability of the TMC system to provide information about the condition of all roads in large cities.  
As of December 1, 2017, Russia is broadcasting RDS-TMC traffic in 23 cities: Vladivostok , Vologda , Voronezh , Yekaterinburg , Irkutsk , Kazan , Kaliningrad , Kirov , Krasnodar , Krasnoyarsk , Moscow , Nizhny Novgorod , Novosibirsk , Rostov-on-Don , Samara , St. Petersburg , Sochi , Tver , Tolyatti , Ufa , Khabarovsk , Chelyabinsk , Yaroslavl .  Traffic data is taken from the Yandex traffic jam resource  and is broadcast in Moscow in the FM band at three frequencies: 99.6 ( Finam FM radio station ), 107.0 ( Russian News Service radio station ), 107.4 ( Hit FM radio station ) MHz .  
In early 2011, NAVTEQ began to provide information on the speed of transport through RDS-TMC in Moscow, and later in St. Petersburg, Yekaterinburg, Nizhny Novgorod, Novosibirsk, Rostov-on-Don, Samara and Kazan. In 2012, Nokia Location & Commerce (previously acquired NAVTEQ) expanded its broadcasting to Krasnodar, Krasnoyarsk, Chelyabinsk, Perm, Tolyatti and Voronezh. In 2013, HERE (a new brand replacing Nokia Location & Commerce in 2013) expanded its broadcasting to Kemerovo, Tyumen, Surgut, Saratov, Naberezhnye Chelny, Izhevsk, Ryazan, Lipetsk, Vladivostok, Sochi and Stavropol. In Moscow, broadcasting is carried out on the frequencies of Autoradio, Romance and Love radio. Also, information about traffic jams in these cities is available through the XML-TMC service (via the Internet), which has more detailed coverage and information about roads without traffic jams (free flow). At the end of 2012, NAVTEQ cards integrated TMS tables of 31 cities of Russia (except for the above, these are Sochi, Vladivostok, Kemerovo, Tyumen, Stavropol, Surgut, Saratov, Naberezhnye Chelny, Izhevsk, Ryazan, Irkutsk, Orenburg, Lipetsk, Barnaul, Volgograd, Omsk). In 2013, HERE cards integrated TMS tables of several other cities of Russia (in addition to the above, these are Moscow within the new borders, Astrakhan, Belgorod, Ulyanovsk, 16 cities of the Moscow Region). All tables are certified by TISA.
In 2012, the NAVTEQ Traffic service was used on the standard navigation systems of Volvo, Land Rover cars, as well as on Alpine devices. In 2013, the HERE Traffic service (RDS TMC) is used on the standard navigation systems of Volvo, Land Rover, Honda cars, as well as on Alpine devices. XML TMC is used on the standard navigation systems of SsangYong Actyon cars, as well as on aftermarket devices [ what? ] for Hyundai Solaris, Kia Rio.
Alternatives to TMC
A growing number of car navigators and cell phones with GPS have the ability to connect to the Internet, and navigation software providers are increasingly using the Internet connection to transmit traffic information online.
TMS was developed over 30 years ago to transmit information about traffic jams on highways. Each section of the road has its own identifier. When a traffic jam occurs, the identifier of the site, the direction of action (in which direction the traffic jam) and its state (idle, traffic jam, repair, traffic accident and much more) are sent to the air. There can be up to 65535 such sections for one TMC table. Navigation receivers compare the received information with the map, and if the map has the same identifiers on the roads, traffic information appears on the screen.
The problems of systems based only on TMS tables are that if some section of the road is not described in TMS tables, then it is not possible to show a traffic jam on it. For many countries poorly covered in TMS tables, this creates a problem. With the reconstruction of roads, TMS tables should also be updated (along with maps). To solve it, they use a new type of description of a traffic jam or other road event, which is not tied to the TMS code of the table, but to geographical coordinates. However, such a description increases the total amount of transmitted data by several times. Therefore, in coding information about traffic jams, it is considered promising to use a combination of both TMS tables, which reduces the amount of data and allows you to describe traffic jams on most roads, as well as descriptions in relation to coordinates, which makes it possible to describe traffic jams on a section of the road that is not encoded in TMS.
- Traffic Receiver . TomTom. Date of appeal June 15, 2014. (unavailable link)
- Archived copy (inaccessible link) . Date of treatment November 27, 2011. Archived on August 12, 2012. TMC-Forum Members
- Software News of May 7, 2007
- http://www.pcweek.ru/themes/detail.php?ID=83842&THEME_ID=13877 Microsoft is on guard of car owners' wallets
- https://web.archive.org/web/20061216015500/http://www.mintrans.ru/pressa/Novosty_050617_1.htm “Seminar. State policy and regulation in the field of car navigation. 05/17/2005 »
- http://www.kommersant.ru/doc.aspx?DocsID=710274 information is the same road element as asphalt. Kommersant 10/12/2006
- Archived copy (inaccessible link) . Date of treatment September 3, 2009. Archived July 21, 2009. CJSC Navikom started broadcasting information on the speed of transport on the roads of Moscow in the format RDS-TMC
- http://forum.garminych.ru/viewtopic.php?t=77 Report on the work of Garmin nuvi 765TFM with TMC service from Navikom
- iXBT.com: Annual joint press conference of Garmin and CJSC Navikom
- List of Russian cities with Navik Traffic service
- Company news: Yandex.Traffic in Garmin navigators (inaccessible link) . Date of treatment November 27, 2011. Archived October 27, 2011.
- Monitoring of Moscow radio broadcasting, list of RDS-TMC radio stations for Garmin
- The beginning of the TMC broadcast in Moscow (St. Petersburg and others) for Garmin
- Automotive Information and Communication System
- Intelligent Transportation System