Defense Dev Solutions- Cursor on Target (CoT) is a small, simple message format that says what something is, where it is and when that is true.
- MITRE created it in 2002 for the U.S. Air Force, to let systems that were never designed to work together share data automatically.
- Its simplicity is the point: any system that can read and write CoT can join the picture, which is why it spread well beyond TAK.
- A CoT type such as a-h-G-U-C encodes affiliation, battle dimension and function, which map onto MIL-STD-2525 and NATO APP-6 military symbols.
- TAK clients use CoT for everything they share, and newer versions can carry the same information in compact binary form as TAK Protocol.
What Cursor on Target is
Cursor on Target (CoT) is a message format for sharing the what, where and when of anything worth tracking. Each CoT message, called an event, describes one thing: what kind of thing it is, where it is, when the information was created and how long it stays valid. That thing can be a person, a vehicle, an aircraft, a sensor detection, a map marker or a point of interest.
CoT messages are usually written in XML and are small enough to send many times a second over modest networks. Every product in the TAK family uses CoT to share data, which is why it comes up in almost every conversation about TAK integration. If you are new to TAK, start with What is ATAK?.
A short history of CoT
Cursor on Target dates to 2002. At a C4ISR summit hosted by the U.S. Air Force's Electronic Systems Center, then Chief of Staff General John Jumper challenged the community to get existing systems sharing information automatically, with as little human effort as possible. In the speech, he put the goal in a single line:
“The sum of all wisdom is a cursor over the target.”
General John P. Jumper, USAF Chief of Staff, 2002
MITRE, working for the Electronic Systems Center, took up the challenge and turned that line into a name. As MITRE's own developer guide notes with some humour, CoT was never really about cursors, and only sometimes about targets. It was about agreeing on the smallest possible common language so that systems built by different programs could exchange the essentials without being redesigned.
The approach caught on quickly. The Air Force established a Cursor on Target program office at Hanscom Air Force Base, ran regular user group meetings, and saw CoT adopted across air, ground and maritime systems. By 2014, MITRE reported CoT operationally deployed around the clock, worldwide, in more than 300 systems. When the Air Force Research Laboratory began building ATAK, CoT was the natural choice for how it would talk to everything else.
Why CoT works
CoT succeeded where larger, more complete data standards struggled, and the reasons are all about restraint. A minimal event looks like this:
<event version="2.0" uid="TGT-0417" type="a-h-G-U-C" how="h-e"
time="2026-10-27T15:20:00Z" start="2026-10-27T15:20:00Z"
stale="2026-10-27T15:50:00Z">
<point lat="36.7310" lon="-76.5790" hae="9" ce="50" le="25" />
<detail />
</event>| Part | What it answers |
|---|---|
uid | Which thing is this? Later messages with the same UID update it rather than adding a new one. |
type | What is it? A hostile ground combat unit, a friendly aircraft, a map point, a chat message. |
point | Where is it, and how accurate is that? Latitude, longitude, height and error estimates. |
time / start / stale | When was this reported, and when should everyone stop trusting it? |
how | How was it produced? Machine-generated GPS, a human estimate, and so on. |
detail | Everything else, from callsigns and remarks to sensor data and links to video. |
- Small core, open edges. Every system agrees on the core fields. Anything system-specific goes into
detail, which other systems can safely ignore if they do not understand it. - Built-in expiry. The
staletime means old information fades out on its own instead of cluttering the map or misleading anyone. - Easy to translate. Because the core is so small, writing a translator from almost any other format into CoT is straightforward. That made it possible to connect existing systems without changing them.
- Transport-agnostic. CoT can travel over whatever network is available, from a local radio network to a server connection across the world.
How systems beyond TAK use CoT
TAK is the best-known user of CoT today, but CoT was built to connect many systems, and it still does. Public examples include:
- Tactical data links and mission planning. MITRE has reported CoT translators for Link 16, the Variable Message Format (VMF), FalconView and Google Earth, letting their data reach CoT-speaking systems and the other way round.
- Close air support. CoT was used to help pass target coordinates to strike aircraft and to share position data with joint terminal attack controllers alongside tools such as ROVER video receivers.
- Disaster response and search and rescue. U.S. Coast Guard briefings on interagency response from Hurricane Katrina to Hurricane Ike describe CoT feeds, including airborne surveillance tracks, being brought into search-and-rescue planning.
- Training and range systems. Joint Range Extension software, used to connect live, virtual and constructive training, has integrated CoT and TAK capabilities.
- Commercial GIS. Platforms such as Esri's ArcGIS Velocity can take in TAK and CoT feeds and bring them into enterprise mapping and analytics.
- Video and sensor tools. Software that reads drone video metadata can output CoT, so an aircraft and its sensor's point of interest appear in any CoT-aware system. Our article on drone video and sensor footprints in ATAK covers this in more detail.
- Open-source projects. Community TAK servers and CoT libraries in many programming languages make it easy for new systems to read and write CoT.
CoT types and NATO military symbols
The type field is where CoT connects to military symbology. A type is a short string of codes separated by hyphens, read left to right from general to specific. Take a-h-G-U-C:
- Atom (a). The event describes a physical thing in the world. Types beginning with other letters describe other kinds of data, such as map points, chat messages and drawings.
- Affiliation (h). Whose side it is on. This is the part most people recognize on the map.
- Battle dimension (G). Where it operates: air, ground, sea surface, subsurface or space.
- Function (U-C). What it is, getting more specific with each code: a unit, then a combat unit, and so on.
| Code | Affiliation | Frame and colour |
|---|---|---|
| f | Friend | Rectangle, blue |
| h | Hostile | Diamond, red |
| n | Neutral | Square, green |
| u | Unknown | Clover shape, yellow |
CoT also defines finer-grained affiliations such as assumed friend, suspect and pending, which follow the same military conventions.
How this relates to MIL-STD-2525 and APP-6
These codes were not invented for CoT. They follow the structure of MIL-STD-2525, the U.S. Department of Defense standard for military map symbols, which is closely aligned with NATO's APP-6 joint military symbology. In both standards, a symbol is built from the same ideas: a standard identity (friend, hostile, neutral, unknown) that sets the frame shape and colour, a battle dimension, and a function that sets the icon inside the frame.
CoT's affiliation, dimension and function codes line up with those parts, so a CoT type can be translated into a military symbol. That is how ATAK can receive a-h-G-U-C from any system and draw the red diamond of a hostile ground combat unit that every trained user recognizes, and how allied systems using APP-6 can show the same picture.
CoT in TAK today
Inside the TAK ecosystem, CoT carries far more than tracks. Positions, map markers, drawn shapes, routes, chat messages, alerts, sensor points of interest and links to video all travel as CoT events, each identified by its type.
Newer TAK clients can also send CoT as TAK Protocol, which carries the same information in a compact binary form built on Protocol Buffers. It saves bandwidth on constrained links, while the underlying model of what, where and when stays the same. Systems that integrate with TAK generally work with both.
Two decades after General Jumper's speech, the idea behind CoT still holds: agree on a few essentials, and very different systems can share one picture. If you need a sensor, system or data source to speak CoT, that is what our TAK integration work is built around, often delivered through ATAK plugins or TAK Server.
Talk to the engineers who wrote this guide.