Service Modeling Language

Service Modeling Language (SML) and Service Modeling Language Interchange Format (SML-IF) are a pair of XML-based specifications created by leading information technology companies that define a set of XML instance document extensions for expressing links between elements, a set of XML Schema extensions for constraining those links, and a way to associate Schematron rules with global element declarations, global complex type definitions, and/or model documents. The SML specification defines model concepts, and the SML-IF specification describes a packaging format for exchanging SML-based models.
SML and SML-IF were standardized in a W3C working group chartered to produce W3C Recommendations for the Service Modeling Language by refining the “Service Modeling Language” (SML) Member Submission, addressing implementation experience and feedback on the specifications. The submission was from an industry group consisting of representatives from BEA Systems, BMC, CA, Cisco, Dell, EMC, HP, IBM, Intel, Microsoft, and Sun Microsystems. They were published as W3C Recommendations on May 12, 2009. In the market and in applying by vendors, SML is seen as a successor/replacement for earlier developed standards like DCML and Microsoft's (in hindsight) proprietary System Definition Model or SDM. See for a historically helpful relation between SDM and DCML, and for the joint pressrelease announcing SML. In the Microsoft section of it the sequel role to SDM is mentioned.
Fast Formal Facts about SML.
The Service Modeling Language (SML) is a language for building a rich set of constructs for creating and constraining models of complex IT services and systems. SML-based models could include information about configuration, deployment, monitoring, policy, health, capacity planning, target operating range, service level agreements, and so on. 
An SML model is a set of interrelated XML documents. An SML model could contain information about the parts of an IT service, as well as the constraints that each part must satisfy for the IT service to function properly. Constraints are captured in two ways:
Once a model is defined, one of the important operations on the model is to establish its validity. This involves checking whether all model documents satisfy the XML Schema and rule document constraints.
SML-Based Models.
Models provide value in several important ways: