Committed to connecting the world

AI for Good Global Summit

XML encoding rules (XER) for ASN.1

​The standardized XML Encoding Rules (XER) allow ASN.1 specifications (modules) to be used as ASN.1 schemas against which XML documents can be validated. As a result, the ASN.1 language now competes with other XML schema languages, but it has some additional benefits over them.

Mapping from XML Schemas to ASN.1 modules

​This standardized mapping takes as input any schema written in XML Schema and produces an ASN.1 module containing a set of type definitions in such a way that there is a one-to-one correspondence between ASN.1 abstract values and valid XML instances.
ASN.1 standardized encoding rules such as DER (a canonical encoding that allows digital signatures and encryption) or PER (to very efficiently transmit data over a radio channel), or even specific encoding rules that are described in ECN, can then be used.
One big benefit of using a binary encoding is speed. Decoding a binary stream improves performance by a factor 100 or more. Another benefit is size: a binary encoding may save up to 80% or even more relative to corresponding XML text.

Fast Web Services

​Fast Web Services is a standard that specifies ASN.1 SOAP messages which carry the same semantics as W3C SOAP messages. This is an extension to the provision of Web services using W3C SOAP messages, without any change to the functionality of W3C SOAP and service description languages.
The main change is to the use of compact and easily-processed binary encodings of XML data, rather than character encodings. The use of Fast Web Services (with the ASN.1 SOAP messages encoded using the ASN.1 Packed Encoding Rules, PER) allows applications to provide Web services using messages that require less network bandwidth and less processing power (and hence provide a higher transaction processing rate) than use of the character encoding of XML data.

Fast Infoset

​Fast Infoset is a standard that specifies a representation of an instance of the XML Information Set using ASN.1 binary encodings. It provides an alternative to W3C XML syntax as a means of representing instances of the W3C XML Information Set.
This representation generally provides smaller encoding sizes and faster processing than an XML representation. Fast Infoset specifies the use of several techniques that minimize the size of the encodings and that maximize the speed of creating and processing those encodings.