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Question M/17 - Abstract Syntax Notation One (ASN.1) and other Data Languages
(continuation of Question 12/17 and parts of Questions 11/17 and 14/17 studied during 2001-2004)

1. Motivation

The Question is responsible for the maintenance of Recommendations X.680, X.681, X.682, X.683, X.690, X.691, X.692, X.693, X.694, X.660, X.662, X.665, X.666, X.667, X.669, X.670, X.671 and X.920.

It will complete work on the development of X.fws (Fast Web Services) and X.finf (Fast Infoset) Recommendations, and will develop additional Recommendations, where needed, to accommodate advances in technology and additional requirements from users of the ASN.1 notation, its Encoding Rules, and additional requirements from users and providers of Registration Authorities.

ASN.1 has proved to be the notation-of-choice for many ITU-T standardization groups, many of which continue to produce requests for additional functionality in the ASN.1 Recommendations, and for correction of residual ambiguities and lack of clarity in those Recommendations (maintenance).

Data may serve many roles relative to a computer system, its interfaces and uses. There is a need to identify these roles and any new language features and notations needed to support them.

There is also a need to provide assistance with the definition and use of data representations (including both binary and XML encoding of data) by other Questions and the development of any necessary Recommendations.

Collaboration should be established with OMG to ensure that any new versions of IDL (X.920) meet ITU-T needs.

2. Question

The study of abstract syntax notation should continue to determine:

a) What enhancements are required to the Abstract Syntax Notation One (ASN.1) and its associated encoding rules to meet the needs of future applications ?

b) What additional Encoding Rule support is needed to provide for the requirements of the many applications using ASN.1 ?

c) Can the Encoding Rule specifications of ASN.1 be more formally defined, and can more flexibility be provided for protocol specifiers to vary those encoding rules ?

d) Are there requirements for additional generic applications of ASN.1 in addition to X.fws and X.finf ?

e) What Recommendations are needed to provide linkage between ASN.1 and other notations for data schema definition, particularly (but not exclusively) related to XML mark-up ?

f) What further work needs to be done to ensure that the semantic underpinning of ASN.1 is sufficient to support the "ASN.1 tools" industry with a well-defined and unambiguous specification of the ASN.1 notation for all possible input specifications ?

g) What collaboration, beyond current agreements, is required with other bodies producing de jure or de facto standards to ensure that ITU-T work on ASN.1 remains a leader in the area of provision of notations for protocol definition ?

h) What additional Registration Authorities or their procedures are needed to support the work of this and other Questions ?

i) What additional Recommendations are needed to support data formats and data structuring and mapping between such formats ?

3. Tasks

a) Complete the work leading to new Recommendations X.fws and X.finf.

b) Provide updated Recommendations for X.660-, X.670-, X.680- andX.690-series throughout the study period in response to user needs.

c) Evaluate and adopt if appropriate new versions of IDL in collaboration with OMG (X.920).

4. Relationships

Recommendations: H.200-series, H.323, T.120, X.400-series, X.500-series, X.700-series, X.880-series, X.900-series, Z-series and many others.

Questions: All Questions related to the above Recommendations

Study Groups: All Study Groups that use ASN.1

Standardization bodies: ISO/IEC JTC 1/SC 6 and all ISO/IEC WGs that use ASN.1; OMG; IETF; W3C; OASIS
Other bodies ASN.1 Consortium


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Updated : 2004-10-21