A tactical data link (TDL) uses a data link standard in order to provide communication via radio waves or cable used by NATO nations. All military C3 systems use standardized TDL to transmit, relay and receive tactical data.
Multi-TDL network (MTN) refers to the network of similar and dissimilar TDLs integrated through gateways, translators, and correlators to bring the common tactical picture and/or common operational picture together.
The term tactical digital information link (TADIL) was made obsolete (per DISA guidance) and is now more commonly seen as tactical data link (TDL).
TDLs are characterized by their standard message and transmission formats. This is usually written as <Message Format>/<Transmission Format>.
In NATO, tactical data link standards are being developed by the Data Link Working Group (DLWG) of the Information Systems Sub-Committee (ISSC) in line with the appropriate STANAG.
In NATO, there exist tactical data link standards as follows:
| Link No | STANAG | Working Title | Final title / description | Communi- cation | Gene- ration | Comments | |
|---|---|---|---|---|---|---|---|
| 1 | 5501 | NATO data link between Air Defence Main Control Centres | Link 1 – Tactical Data Exchange for Air Defence | Point-to-point | 1st S–Series | Ground Link between NADGE entities limited and not secure | |
| 2 | Radar to Control Centre Data Link | 1st | Cancelled (includes in Link 1) | ||||
| 3 | Control Centre to higher HQ Data Links | SHOC Early Warning System | Point-to-point | 1st | Slow Speed Warning Link from evaluation centres to SHAPE | ||
| 4 | 5504 | Ground to Air Data Link | Link 4 – TDL for the Control of Military aircraft | Point-to-point | 1st C/R–Series | Compatible to US TADIL–C to be operated in NATO UHF (225–400 MHz) RF band | |
| 5 | Fast HF Automatic Link | Broadcast | 1st | Cancelled (see Link 11) | |||
| 6 | 5506 (Draft) | Missile Base to Control Centre Link | Link 6 – (NADGE Link) SAM Automatic Data Link | Point-to-point | 1st | Draft STANAG (US MBDL, ATDL–1, PADIL) | |
| 7 | 5507 (Draft) | ATC / Defence Link | Link 7 – TDL for ATC | Point-to-point | 1st | ||
| 8 | HF Automatic Link | Broadcast | 1st | Cancelled (see Link 1) | |||
| 9 | SOC / Airbase Link | 1st | |||||
| 10 | 5510 | Ship – Ship Link | Link 10 – Maritime Tactical Data Exchange | Broadcast | 2nd M–Series | STANAG cancelled (was used by BE, NL and UK) | |
| 11 | 5511 | Fast HF Automatic Link | Link 11 – Maritime Tactical Data Exchange | Broadcast | 2nd M–Series | Compatible to US TADIL–A to be operated in the HF & NATO UHF RF bands | |
| 11B | 5511 (Vol. II) | Link 11B – Tactical Data Exchange | Point-to-point | 2nd M–Series | Compatible to the US TADIL–B Ground to Ground TDL | ||
| 12 | Fast HF Automatic Link | Cancelled (see Link 11) | |||||
| 13 | HF Automatic Link | Broadcast | Cancelled (see Link 11) | ||||
| 14 | 5514 | Slow Semi–Automatic Link | Link 14 – Maritime TDL | Broadcast | 1st D/M/S/E–Series | Ship–Ship & Ship–Shore (only few applications) | |
| 15 | Slow Semi–Automatic Link | Ship–Ship, Cancelled | |||||
| 16 | 5516 | High Capacity, ECM Resistant, Multifunctional, TDMA Link | Link 16 – ECM Resistant Tactical Data Exchange | Broadcast | 3rd J–Series | Compatible to US TADIL–J (STANAG 4175 – Technical Characteristics of MIDS) | |
| 21 | 5521 (Draft) | Link in support of ACCS – (LISA) | Point-to-point | 3rd J–Series | Under development (planned to replace Link 1 and Link 11B) | ||
| 22 | 5522 (Draft) | NATO Improved Link 11 – (NILE) | Link 22 | 3rd J–Series | Under development (planned to replace Link 11) | ||
| 5601 | Standard for Interface of Data Links 1, 11, 11B, and 14 through a buffer | see AdalP 12 | |||||
| 5602 | Standard Interface for Multiple Platform Link Evaluation (SIMPLE) | Enables transmission of J-Series (TADIL-J) messages over IP-based protocols | |||||
| MIL-STD-6020 | 5616 | Standard for data forwarding between tactical data systems employing Links 11/11B and tactical data systems employing Link 16 | MIL-STD-6020, DoD Interoperability Standard: Data Forwarding between TDLs | ||||
| IJMS | ECM Resistant Communication System (ERCS) | IJMS – Interim JTIDS/MIDS Message Specification | Broadcast | 2nd, M–Series | Interim Data Link Standard to be replaced by Link 16 | ||
| SADL | Situational Awareness Data Link | SADL – Situational Awareness Data Link | Broadcast | 1st, K-Series 2nd, K/J–Series | Data link adopted from EPLRS to provide A-10s and F-16s data link capability air-to-ground and air-to-air |