本文档定义了用于指定ASN编码的符号。1.类型或类型的部分
它为这种规范提供了几种机制，包括:
–使用标准化符号直接指定编码
–参考标准化编码规则对编码进行规范
–ASN编码规范。1.参照编码结构输入
–使用非ECN符号的编码规范
它还提供了将编码规范与要应用编码的类型定义联系起来的方法
ECN目前不支持使用OID国际化资源标识符类型或相关OID国际化资源标识符类型的规范（见建议ITU-T X.680 | ISO/IEC 8824-1），本标准中未进一步提及这些规范。

This document defines a notation for specifying encodings of ASN.1 types or of parts of types.
It provides several mechanisms for such specification, including:
– direct specification of the encoding using standardized notation;
– specification of the encoding by reference to standardized encoding rules;
– specification of the encoding of an ASN.1 type by reference to an encoding structure;
– specification of the encoding using non-ECN notation.
It also provides the means to link the specification of encodings to the type definitions to which they are to be applied.
ECN does not currently provide any support for specifications using the OID internationalized resource identifier type or the relative OID internationalized resource identifier type (see Rec. ITU-T X.680 | ISO/IEC 8824-1), and these are not referred to further in this Standard.