Computer Security Resource Center

Computer Security Resource Center

Computer Security
Resource Center

A  |  B  |  C  |  D  |  E  |  F  |  G  |  H  |  I  |  J  |  K  |  L  |  M  |  N  |  O  |  P  |  Q  |  R  |  S  |  T  |  U  |  V  |  W  |  X  |  Y  |  Z

{ }

Abbreviation(s) and Synonym(s):

None

Definition(s):

  In this Recommendation, the curly braces { } are used in the following three situations: (1) {x} is used to indicate that the inclusion of x is optional; for example, the notation “Input: w, {x}, y, and z” implies that the inclusion of x as an input is optional. (2) If both X and Y are binary strings, the notation of binary string “Y{||X}” implies that the concatenation of string X is optional. (3) {x1, x2, …, xk} indicates a set with elements x1, x2, …, xk.
Source(s): NIST SP 800-56A Rev. 2