Abstract
Abstract Syntax Notation One (ASN.1) is a framework for representing tree structured data. Since ASN.1 data are structured data, it should be possible to represent the same information in Extensible Markup Language (XML). The translation between ASN.1 and XML will enable us to manipulate efficient ASN.1 data in a user-friendly manner. We develop a Java library for such translation, called ASN.1/XML translator. We also confirm actual ASN.1 data were translated into expected XML documents and these documents were translated back into the original data if the data were encoded according to Distinguished Encoding Rules (DER). Moreover we discuss still existing issues and try to address them, especially support of XML Schema.