text: Security Operations
  units to execute it. Often, the counterreconnaissance plan requires a unit to conduct a screen mission to
  acquire, identify, and defeat enemy reconnaissance forces.
  5-16. The counterreconnaissance force must be task organized to accomplish its mission with the enemy.
  Whatever option the commander employs, the counterreconnaissance fight should be firmly controlled,
  monitored at the higher headquarters level, coordinated early, and thoroughly rehearsed. An effective
  counterreconnaissance fight suppresses the enemy reconnaissance effort, forcing the enemy to attack without
  information about the friendly force disposition.
  SECTION III – SECURITY TYPES
  5-17. Leaders categorize security operations in terms of the degree of security provided and the amount of
  combat power required. (Refer to ADP 3-90 for more information.) The four primary types of security
  operations are—
  * Screen.
   Stationary.
   Moving (flank and rear).
  * Guard.
   Advance guard (stationary and moving).
   Flank guard (stationary and moving).
   Rear guard.
  * Cover.
   Offensive cover (advance and flank).
   Defensive cover (front, flank, and rear).
  * Area security.
   Route security.
   Convoy security.
  5-18. The four types of security operations provide varying levels of protection to the protected force and
  are dependent upon the size of the unit conducting the security operation. Screen operations provide early
  warning to the main body. Guard operations prevent enemy observation and direct fire on the main body.
  Cover operations protect the main body from enemy observation and effective direct fire. Area security
  protects friendly installations, routes, units, and facilities within a prescribed area. All types of security
  operations provide protection and early warning to the protected force, which in turn, provides reaction time
  and maneuver space to the commander and preserves freedom of action. Commanders should consider the
  following when assigning a security mission and employing a security force:
  * Force or area to secure.
  * Location and orientation of the security area.
  * Initial location and types of observation posts, if applicable.
  * Time allocated to establish the security operation.
  * Criteria for transitioning from the security operation to BCT decisive operations.
  * Task organization and augmentation of security forces.
  * Level of protection and minimum warning time requirements.
  * Threat considerations, such as the smallest enemy element allowed passage without engagement
  or the threat’s capability to influence main body activities.