1. [n]  code of correct conduct; "safety protocols"; "academic protocol"
2. [n]  forms of ceremony and etiquette observed by diplomats and heads of state
3. [n]  (computer science) rules determining the format and transmission of data

1. \Pro"to*col\, n. [F. protocole, LL. protocollum, fr.
   Gr. ? the first leaf glued to the rolls of papyrus and the
   notarial documents, on which the date was written; prw^tos
   the first (see {Proto-}) + ? glue.]
   1. The original copy of any writing, as of a deed, treaty,
      dispatch, or other instrument. --Burrill.
   
   2. The minutes, or rough draught, of an instrument or
      transaction.
   
   3. (Diplomacy)
      (a) A preliminary document upon the basis of which
          negotiations are carried on.
      (b) A convention not formally ratified.
      (c) An agreement of diplomatists indicating the results
          reached by them at a particular stage of a
          negotiation.
   
   
   
   

2. \Pro"to*col\, v. t.
   To make a protocol of.
   
   

3. \Pro"to*col\, v. i.
   To make or write protocols, or first draughts; to issue
   protocols. --Carlyle.
   
   

A set of formal rules describing how to transmit data, especially across a network. Low level protocols define the electrical and physical standards to be observed, bit- and byte-ordering and the transmission and error detection and correction of the bit stream. High level protocols deal with the data formatting, including the syntax of messages, the terminal to computer dialogue, character sets, sequencing of messages etc.

Many protocols are defined by rfcs or by osi.

See also handshaking.

[jargon file]