Abstract Syntax Notation One

Abstract Syntax Notation One (ASN.1) is a standard for describing structured data. Combined with a standard for encoding this data, such as BasicEncodingRules? (BER), DistinguishedEncodingRules? (DER), CanonicalEncodingRules? (CER), or PackingEncodingRules? (PER), it can serve as one of the AlternativesToXml.

Overview of ASN.1: http://www.oss.com/asn1/overview.html

Summary with examples of ASN.1 and BER: http://support.microsoft.com/kb/252648/en-us

ASN.1 with BER is used as the basis for SimpleNetworkManagementProtocol (SNMP) and MessageHandlingServices? (MHS), for example.

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A variety of data encoding standards for transmission of data defined by an ASN.1 structure:

BER

(BasicEncodingRules?) "was created in the early 1980s and is used in a wide range of applications, such as Simple Network Management Protocol (SNMP) for management of the Internet; Message Handling Services (MHS) for exchange of electronic mail and TSAPI for control of telephone/computer interactions."

DER

(DistinguishedEncodingRules?) specialized high-security form of BER

CER

(CanonicalEncodingRules?) large encrypted messages (and incremental parsing -- like SAX, for XML)

PER

(PackingEncodingRules?) "faster and more compact encodings than BER. PER is used in applications that are bandwidth or CPU starved, such as air traffic control and audiovisual telecommunications."

XER

(XML Encoding Rules) ASN.1 in XML.

E-XER

"(Extended XML Encoding Rules) [...] ASN.1 an XML schema notation as powerful as XSD, with the simplicity of ASN.1."