The methods of communications used by DF nets are landline teletypewriter, radio teletypewriter, CW, and radiotelephone. All of these methods of communications must be secured with cryptosystems. A prime consideration of a DF net is the security and speed with which its users may effectively, communicate.
Job descriptions and qualification factors for United States Army Enlisted Jobs (Military Occupation Specialties). On this page, all about 35N - Signals Intelligence Analyst
The application Cryptool is a free e-learning application for Windows. You can use it to apply and analyze cryptographic algorithms. The current version of Cryptool is used all over the world. It supports both contemporary teaching methods at schools and universities as well as awareness training for employees.
What is Electronic Intelligence (ELINT)? ELINT is information derived primarily from electronic signals that do not contain speech or text (which are considered COMINT). Cryptologic History Center - NSA pdf file.
Radio Fingerprinting. 1960's to 21st century. World War Two. From an old timer's memoirs : The USN radio intelligence organization grew from 75 officers, ... No attribution