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COSEM APDU ASN.1 specification and XML schema

ITU-T recommendations X.693 and X.694 provide XML encoding rules to Abstract Syntax Notation 1 (ASN.1) and XML Schema Definitions Language (XSD) mapping to ASN.1. No recommendation is provided to map ASN.1 to XSD.

Here COSEMpdu ASN.1 definition is provided and mapped to COSEMpdu XSD definition.

XML has gained wide acceptance in the IT industry.

The purpose of such encoding is to enable transfer of COSEM model content with various means in the form of XML encoded content. It can be a XML document exchanged between applications, content included in Web services SOAP messages or content encapsulated in e-mail messages, to name just few of the applications.

Interoperability and mapping between ASN.1 encoded APDUs and XML encoded content is important in both directions. On one side ASN.1 has enabled creation of XML encoded content with support for XML Encoding Rules (See ITU-T X.693 and ITU-T X.694). On the other hand the IT industry is searching for solutions for optimal transfer of XML content with XML optimized packaging. For that purposes conversion between W3C XML Schema and ASN.1 definition is crucial. Conversion in both directions enables proper conversion of XML content to ASN.1 encoded content and vice versa.