Currently Online 
As Ukrainian troops assault, Russian forces move reinforcements and fire artillery in response, exposing their positions and defensive strategies. They switch on electronic jamming systems, revealing how this equipment will be used in the fighting.
The Ukrainian military is using what it learns in these assaults to strike Russian artillery positions, said Mr. Samus, softening up defenses for an actual breakthrough battle that will come later. The larger fight "is still ahead of us and where exactly it will be we still don't know."
The main Russian defensive tactic, military analysts have said, is to deploy a thinly manned first line to detect an assault as it is overrun. Behind this line are minefields and then more trenches. Even farther back are reinforcements, which rush forward to counterattack the assaulting troops as they try to cross the minefields.
With Probes of Russian Lines, Ukraine’s Counteroffensive Takes Shape - The New York Times
