This Recommendation I International Standard specifies a set of basic
encoding rules that may be used to derive the specification of a
transfer syntax for values of types defined using the notation specified
in ITU- T Rec. X.680 I ISO/lEG 8824-1, ITU-T Rec. X.681 I ISOIlEG 8824-
2, ITU-T Rec. X.682 I ISO/lEG 8824-3, and lTU-T Rec. X.683 I ISO/lEG
8824-4, collectively referred to as Abstract Syntax Notation One or
ASN.I. These basic encoding rules are also to be applied for decoding
such a transfer syntax in order to identifY the data values being
transferred. It also specifies a set of canonical and distinguished
encoding rules that restrict the encoding of values to just one of the
alternatives provided by the basic encoding rules.
These encoding rules are used at the time of communication (by the
presentation service provider when required by a presentation context).