A system built into the hull of its host vessel, the Internal Electronic Countermeasure is classified as such because it doesn't launch any EWAR systems like the Sturm Electronic Countermeasure. There are several types of Internal ECM based upon the size and configuration of the host vessel.

The various models of ECM.

Built for the rigors of large-scale space combat, the Capital Ship ECM prioritizes the disruption of targeting systems over sensor systems.

While classified as a combat-based ECM system, the Cruiser/Escort ECM is considered a well-balanced system between combat capabilities and recon capabilities. Because of this, it has an equal priority in both targeting disruptions, sensor disruption, and communication disruption.

Primarily a recon-based ECM System, the Scout ECM prioritizes Sensor and Communication disruption rather than targeting disruption.

Due to the size constraints of a Strike Craft (fighters and drones) and Ground Vehicles (Tanks), the Strike Craft/Ground Vehicle ECM leaves targeting disruption to the Sturm Electronic Countermeasure while taking the role of sensor and communication disruption.

The various modules of ECM.

A standard Electronic Countermeasure since the Age of Conflict, the Electronic Scrambler is a “noise” generator used to flood either a single frequency or group of frequencies used by electromagnetic detection and/or communication devices. The effectiveness of the Scrambler is based upon the power output of the host vessel and the tactics of its operator.

Using the repeater version of electronic countermeasures, the Electromagnetic Deceiver receives electromagnetic emissions and then sends false readings/signals back to the transmitting source.

Based upon the old Pulse method of the gravatronic radar, the Graviton Pulse Generator pretty much sends ripples through the fabric of space-time to interfere with gravity based detection equipment as well as send false or distorted reading to Starship Subspace Mass.