What are Traffic Location Tables (TMC) and how are they used in HERE map data?

SYMPTOMS / TRIGGERS

You may need this article if:

You need to understand what TMC location codes are and how they relate to HERE map data.
You received traffic data with TMC codes and need to decode them against a location table.
You are trying to identify which traffic location table version is used in your HERE map delivery.
You see references to EBU country code, LTN, or location_code in your data and do not know what they mean.
* You need to request a new TMC code or report incorrect TMC coding in the HERE map.

QUICK ANSWER

A Traffic Location Table (TLT) is a set of pre-defined, hierarchically structured locations identified by numeric codes (TMC codes). Traffic services use these codes to reference specific road positions in traffic messages. Your navigation system or application decodes incoming TMC codes against the matching location table to display traffic information on the correct road segment.

To find which table is included in your HERE map delivery, check the TMC metadata in your map format:
RDF format: query the RDF_LINK_TMC table.
GIS Data Suite: check the Streets_TMC table (Fields: EBU_COUNTRY_CODE, LOCATION_TABLE_NR, LOCATION_CODE).
HMC format: check the navigation-attributes layer for TrafficMessageChannelCodeAttribute.

HOW TRAFFIC LOCATION TABLES WORK

Traffic location tables follow a hierarchical structure with three levels:

1. Areas — Represent larger regions (countries, states, counties). These correspond to the administrative structure in the HERE database.
2. Linear locations — Represent named road stretches (e.g., highways). A linear location is a path of consecutive road elements along a road whose TMC codes correspond to a named road.
3. Point locations — Represent specific points on the road network. This is what is typically referred to as "the TMC location." Traffic providers tie incoming traffic conditions to the TMC code, which is then transmitted in the HERE traffic feed.

A system of pointers provides upward references from point locations to linear locations and from linear locations to areas.

KEY FIELDS IN HERE MAP DATA

When working with TMC data in HERE map extracts, you will encounter these fields:

EBU_COUNTRY_CODE: identifies the country (European Broadcasting Union code).
LOCATION_TABLE_NR (LTN): identifies the specific table within a country (1–63).
LOCATION_CODE: the 5-digit point location code.
TMC_PATH_DIRECTION: direction coding (N = internal negative, P = internal positive, - = external negative, + = external positive).
ROAD_DIRECTION: direction relative to digitized direction (F = from ref node, T = to ref node, B = both).

HOW TO REPORT TMC ISSUES

To request a new TMC code or report incorrect TMC coding in the HERE map:

1. Open the HERE Support Portal (HERESUP).
2. Select parent product: HERE Traffic.
3. Select component: Real-Time Traffic.4
4. Describe the TMC issue (new code request, incorrect coding, or missing table).

STANDARDS AND SPECIFICATIONS

Traffic location tables follow the international standard CEN/ISO TS 14819-3. Table versions are certified by the Traveller Information Services Association (TISA). New table versions are announced via TNM (Technical Network Maintenance) notifications.

ADDITIONAL REFERENCES

HERE Customer Technical Reference Guide (CTRG) — contains detailed TMC coding specifications per map format (RDF Appendix B, GDF Appendix C, File Geodatabase Appendix G, NAVSTREETS section 7.19.2).
Traffic Location Table versions and 3rd party contacts: see CTRG document "Traffic Location Tables (TMC) Table Versions and 3rd Party Contacts".
Non-restricted tables are delivered as additional content via the B2B Customer Download portal (EDD).
Restricted tables must be obtained directly from the table supplier.