Code word
From Free net encyclopedia
- For other uses, see Code word (disambiguation).
In telecommunication, the term code word has the following meanings:
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Cryptonym
A cryptonym used to identify sensitive intelligence data.
Classified information in the United States
A word that has been assigned a classification and a classified meaning to safeguard intentions and information regarding a classified plan or operation. This may allow the plan to be discussed or mentioned briefly without revealing its nature; the Manhattan Project was a famous example of an outright misleading code word.
Cryptography
Main article: Cryptography
A Code differs from a Cipher in that it operates on letter or word boundaries. In a code, a word that consists of a sequence of symbols assembled in accordance with the specific rules of the code and assigned a unique meaning. (e.g. Gray code).
Brevity Codes & Data compression
Main article: Data compression
A code may also be used to represent a compressed form of a word, phrase or data. (e.g. Huffman Code).
Clarity & Disambiguation
Phonetic code word systems are unambiguous words that can be pronounced and understood by those who transmit and receive voice messages by radio or telephone regardless of their native language, especially when the safety of navigation or persons is essential. Normally, uncommon and highly differentiable words are selected to represent otherwise ambiguous letters, numbers or words in order to clarify potentially confusing communication. Ideally, such code words are uniformly pronounced by all speakers. One such system in practical use is the NATO phonetic alphabet which principally addresses the homophony of distinct letter/number names across languages and the near-homophony of many letter/number names within single languages. For example it is difficult to distinguish between the number 3 and the letters b, c, d, e, g, p, t, v and z in spoken American English; however, the NATO phonetic alphabet replace the common words with TREE, BRAVO, CHARLIE, DELTA, ECHO, GOLF, PAPA, TANGO, VICTOR and ZULU respectively.
Radio Communication Procedure Words
Source: from Federal Standard 1037C and MIL-STD-188 and Department of Defense Dictionary of Military and Associated Terms and the UNHCR Procedure for Radio Communication
- SOS is a general distress call used by ships and aircraft worldwide. It was created in the early days of radio telegraphy, because of its simple Morse code structure ( ... --- ... ) and subsequently the backronym Save Our Souls was coined.
- Mayday is a general distress call, similar to SOS, though it's generally used in voice communication. Some say it's from the French m'aidez, meaning simply 'help me'. However, many official sources say it's made up as it is easy to remember, understand, and cannot be mixed up with other words. Do not use the keyword MAYDAY unless you are aboard a vessel or aircraft which is in immediate danger of sinking or crashing.
- Roger, a term used to acknowledge a radio transmission. Can also be used in direct conversation, such as between pilot and co-pilot.
- WILCO, means "I have received and understood your message and will comply (Only used by the addressee)"
- Say Again, a term that requests the sender repeat all of the last transmission.
- Over, a term used to indicate one is done talking. Early radio systems used just one channel for talking and receiving. Neither party can transmit and receive at the same time, so control of the conversation has to be handed over. This allows a rudimentary but effective form of manual Handshaking.
- Out, a term used to end a transmission (never properly used with OVER).
- Ten-Four or "10-4", another term used to acknowledge transmissions. It is one of the Ten-codes made popular during the CB craze of the 1970s.