Encoding functions and methods generated by the ASN1C compiler are designed to be similar in use across the different encoding rule types. In other words, if you have written an application to use the Basic Encoding Rules (BER) and then later decide to use the Packed Encoding Rules (PER), it should only be a simple matter of changing a few function calls to accomplish the change. Procedures for such things as populating data for encoding, accessing decoded data, and dynamic memory management are the same for all of the different encoding rules.

This section describes common procedures for encoding or decoding data that are applicable to any of the different encoding rules. Subsequent sections will then describe what will change for the different rules.