Abstract Syntax Notation One (ASN.1)

An international standard for classifying data structures. It specifies 27 data types with tag values starting with 1; for example, Boolean (1), integer (2), and bit string (3). ASN.1 uses additional rules to designate physical data. The primary set is the Basic Encoding Rules (BER), which are often considered synonymous with ASN.1. ASN.1 is widely used in ground and cellular telecommunications as well as in aviation.