A kinetic barrier uses mass effect technology to create a force field that repels or deflects objects that enter the field at dangerous speeds. Basic barriers simply "push back" against the projectile, slowing it to a harmless speed or (if strong enough) stopping it entirely. Advanced "cyclonic" barriers apply lateral force to projectiles, deflecting them so they miss the target.
Barrier technology is only effective against physical projectiles; barriers provide virtually no protection against directed-energy weapons.
Like all mass effect technology, barrier technology is scalable. Barrier generators can be installed in everything from dreadnought-class starships to personal body armor. Barriers can even be created by individuals with biotic abilities.