text: Chapter 1
  Figure 1-3. The electromagnetic spectrum
  TRENDS AND CHARACTERISTICS
  1-30. The rapid proliferation of cyberspace and EMS capabilities has further congested an already
  challenging OE. In addition to competing with threat actors in cyberspace and the EMS, U.S. forces also
  encounter challenges resulting from neutral actors. Such neutral systems as commercial aircraft and airports,
  Worldwide Interoperability for Microwave Access, and commercial cellular infrastructures contribute to
  continuing congestion in cyberspace and the EMS. Figure 1-4 on page 1-9, depicts cyberspace and the EMS in
  a congested OE.
  1-31. Several key trends and characteristics impact a commander’s ability to use cyberspace and the EMS.
  Such trends and characteristics include—
  * Congested environments.
  * Contested environments.
  * Threats.
  * Hazards.
  * Terrain.
  CONGESTED ENVIRONMENTS
  1-32. Both cyberspace and the EMS are increasingly congested environments that friendly, neutral, and
  threat actors use to transmit and process large amounts of information. Since 2000, the Army’s use of networked
  information systems in almost every aspect of operations has increased tenfold. Neutral and threat actors have
  similarly expanded their use of cyberspace and the EMS for a wide range of military and non-military purposes.