CSA ISO/IEC 8825-7:20
Information technology — ASN.1 encoding rules: Specification of Octet Encoding Rules (OER)
This Recommendation | International Standard specifies a set of Basic Octet Encoding Rules (BASIC-OER) that may be
used to derive a transfer syntax for values of the types defined in Rec. ITU-T X.680 | ISO/IEC 8824-1, Rec. ITU-T X.681
| ISO/IEC 8824-2, Rec. ITU-T X.682 | ISO/IEC 8824-3, Rec. ITU-T X.683 | ISO/IEC 8824-4. This Recommendation |
International Standard also specifies a set of Canonical Octet Encoding Rules (CANONICAL-OER) which provides
constraints on the Basic Octet Encoding Rules and produces a unique encoding for any given ASN.1 value. It is implicit
in the specification of these encoding rules that they are also to be used for decoding.
The encoding rules specified in this Recommendation | International Standard:
– are used at the time of communication;
– are intended for use in circumstances where encoding/decoding speed is the major concern in the choice
of encoding rules;
– allow the extension of an abstract syntax by addition of extra values for all forms of extensibility described
in Rec. ITU-T X.680 | ISO/IEC 8824-1.