45. Intelligence Sources – 3. SIGINT

In blog entry Number 19 I posted a brief explanation of how intelligence works and the general categories of intelligence sources. I want to significantly expand that now, to present the complexity of gathering intelligence data in the modern world.

Sources are classified into about eight categories. Finished intelligence (for dissemination) is a fitting together of pieces from overlapping sources. In the following entries I will present each of these sources. I will review the sources here.

1. Open Sources


2. HUMINT


3. Signal interception – SIGINT


4. Imagery


5. Measurement and Sensing




1. MASINT


2. UGS




6. Scientific and Technical Intelligence


7. Other




1. Diplomatic reports


2. Liaison relationships


3. Interrogation

Signals Intelligence. Known as SIGINT, this is information gathered from interception of signals. SIGINT is a category of intelligence comprising, either individually or in combination, all communications intelligence. It is derived from foreign communications and electronics signals in two principal categories, COMINT; and ELINT. It also includes foreign instrumentation signals intelligence (TELINT) and FISINT. The general categories of SIGINT are:

1. COMINT— Communications Intelligence derived from the intercept of foreign communications. COMINT usually requires decryption and decoding. Enigma machines (Ultra, etc.) are examples of methods of denying communication information from other countries by encryption. During WW II codebreakers radically changed the war by breaking very difficult codes. The Germans used several methods, including Geheimschreiber (secret writer) – the traffic was known a Fish. For some of these machines, the Allies could read the messages almost in real time. Japan had "System 97 Printing Machine for European Characters" or Angōki Taipu-B, codenamed Purple by the Allies. The decrypted traffic was known as Magic. Decryption of Soviet traffic (after WWII) led to the Venona project and identification of several Soviet as well as British and American agents. In current times, the cell phone is an excellent device for counterintelligence. All terrorists carry cell phones. They are trackable, and provide many bits of information, even DNA if they are found abandoned.
   
2. ELINT—Electronic Intelligence derived from the analysis of foreign noncommunications and electromagnetic radiation emitted from other than nuclear detonations or radio-active sources.
   
3. TELINT—Telemetry Intelligence: the collection and analysis of telemetry data from the target’s missile or sometimes from aircraft tests.
   
4. FISINT—Foreign Instrumentation Signals Intelligence
   

NSA is responsible for the US SIGINT program. Each military service has a service cryptological agency, operationally directed by NSA through the Central Security Service (CSS), to ensure missions are properly assigned and duplication of effort is avoided. In the Air Force, this mission is assigned to Air Intelligence Agency (AIA). The Army Intelligence and Security Command (INSCOM) and the Naval Security Group (NSG) make up the remaining agencies of the military NSA and CSS structure. The Director of NSA also serves as Chief of CSS.

SIGINT has many uses, but its application requires a thorough knowledge of the product. Order of battle depends heavily on correlation and analysis of COMINT and ELINT. Mission route planning requires current intelligence on enemy defensive positions and capabilities. Targets can be detected and located through airborne direction finding techniques. Intelligence concerning enemy operational plans may be obtained through signal analysis or cryptologic procedures. Confirmation of other types of intelligence can be made by targeting personnel with the aid of SIGINT reports. Finally, post strike or attack data and damage resulting from missions may also be obtained.

1. Advantages of SIGINT




1. Potential for almost instantaneous information


2. Can sometimes reveal specific information on enemy units


3. Levels of activity and significant changes in these levels can often be determined


4. Organizational structure and order of battle may be obtained


5. Can cue other systems


6. Equipment capability can be learned


7. Emitter location can be approximated or pinpointed (dependent on accuracy capability of the system)


8. Site function can be determined




2. Limitations of SIGINT




1. Data may be denied by use of secure communications


2. False information may be passed by the enemy for deception purposes


3. Collection subject to atmospheric conditions


4. Locations derived from SIGINT may be imprecise


5. Specially configured collection platforms required


6. Use of SIGINT collection platforms requires extensive coordination between collectors and users

The next entry will be on Imagery.