text: Operational Art and Science
  2-136. As the size of the operational force increases, so must the sustainment force required to support it.
  Planners must ensure that sustainment units are built into the force flow to complement operations. As much
  of the Army’s sustainment capability resides in the Reserve Components, planners need to anticipate and
  plan for the additional lead-time required to mobilize and deploy those forces. Additionally, once operations
  commence and friendly forces seize terrain, additional sustainment units will need to traverse the additional
  distance between the JSA and the forward line of troops. For every increase of approximately 100 miles
  (161 kilometers) in operational depth, an additional echelon of distribution resources will need to conduct
  sustainment operations.
  Sustainment Nodes, Lines of Communication, and Modes
  2-137. In developing the initial concept of sustainment, commanders will place their assigned sustainment
  resources to support operations. Sustainment headquarters at each echelon also bear the responsibility for
  integrating additional sustainment assets, such as Army Health Support and forward-positioned assets from
  higher echelon headquarters into the overall plan. At the operational level, maintaining the lines of
  communication is vital to ensure continual support to the mission. This is typically accomplished in
  conjunction with the echelon’s rear command post, as these units may occupy a significant amount of terrain
  in the rear area and will often require security assistance.
  2-138. As friendly forces advance, additional sustainment nodes will need to ensure sustainment remains
  responsive to operational demands. The security of these nodes and the lines of communication that connect
  them will require additional combat power to secure. Commanders introduce protection assets, such as air
  defense, route clearance, and maintenance, to ensure uninterrupted movement of sustainment forward.
  Movement control, particularly in the corps and division areas, becomes vital, as the ability to distribute
  needed materiel forward can be constrained by the availability of transportation or the capacity of the lines
  of communication to accommodate the required traffic. Constant coordination between the corps and division
  transportation officers, ESC, and division sustainment brigade, and their supporting MEBs is required to
  prevent shortfalls of critical supplies in close operations.
  PROTECTION
  2-139. Protection is the preservation of the effectiveness and survivability of mission-related military and
  nonmilitary personnel, equipment, facilities, information, and infrastructure deployed or located within or
  outside the boundaries of a given operational area (JP 3-0). Commanders protect the force through the
  protection warfighting function—the related tasks and systems that preserve the force so the commander can
  apply maximum combat power to accomplish the mission (ADP 3-0). The protection warfighting function
  includes these tasks:
  * Conduct survivability operations.
  * Provide force health protection.
  * Conduct CBRN operations.
  * Provide explosive ordnance disposal (EOD) support.
  * Coordinate air and missile defense support.
  * Conduct personnel recovery.
  * Conduct risk management.
  * Implement physical security procedures.
  * Apply antiterrorism measures.
  * Conduct police operations.
  * Conduct detention operations.
  * Conduct population and resource control.
  * Conduct area security.
  * Perform cyberspace security and defense.
  * Conduct electromagnetic protection.
  * Implement operations security.
  * Airspace planning and management.