Glossary

Abstract Syntax Notation One, a language used to describe the complex data structures independently from the underlying hardware. ASN.1 is a standard developed by the ITU-T and is described in X.680-X.694. ASN.1 is used in the H.323 and 3G-324M Recommendations in order to describe all the messages that are exchanged between two or more entities.

There are several different ways in which ASN.1 messages can be encoded into a binary format. The two most common ones are BER and PER.

A good, in depth book about ASN.1 is ASN.1 Complete by John Larmouth. It does have a few minor mistakes in its PER encoding examples though.