Ecma International, producer of standards for information and communication technology (ICT) and consumer electronics (CE), has announced the approval of Standard ECMA-269: Services for Computer Supported Telecommunications Applications (CSTA) Phase III as an official standard.

ECMA-269 together with a series of related publications, provides "a complete toolbox for developing a wide range of enterprise CSTA applications taking advantage of Internet technologies such as XML, SIP, and speech recognition and processing."

CSTA specifies an Applications Interface and Protocols for monitoring and controlling calls and devices in a communications network. These calls and devices may support various media and can reside in various network environments such as IP, Switched Circuit Networks, and mobile networks. CSTA however, abstracts various details of underlying signalling protocols (e.g., SIP/H.323) and networks for the applications.

The revised third edition of ECMA-323, XML Protocol for Computer Supported Telecommunications Applications (CSTA) Phase III, specifies a set of XML schemas for this 6th edition of Phase III Services for CSTA. The second edition of ECMA-348, Web Services Description Language (WSDL) for CSTA Phase III specifies a set of WSDL schemas for the approved 6th edition of Phase III Services for CSTA.

Ecma CSTA "supports a range of application landscapes, from basic first party call control to advanced third party call control with the same standardised model. CSTA exposes advanced communication platform features to application developers without burdening them with underlying protocol specifics.

All of the Standards and Technical Reports in the CSTA suite "are based on practical experience of ECMA member companies and each one represents a pragmatic and widely-based consensus."

CSTA provides some twenty-six "Call Control features (making call, answering call, etc.), six Call Associated features (sending user data, etc.), and nineteen Logical Device features (do not disturb, forwarding, etc.) It also defines Physical Device features (writing to device display, etc.), Capability Exchange features (feature discovery, etc.), Snapshot features (query existing calls at a device, etc.), and Monitor features (subscribing to event reports, etc.). There are seventeen Voice Services (for Listener, DTMF, Prompt and message resources) along with Routing services, Media Attachment services, Maintenance services, Data Collection services, Accounting services, etc. However, a conforming implementation does not need to support all of these features. There are profiles for basic telephony and routing, as well as three voice browser profiles and six SIP phone profiles (uaCSTA)."

The CSTA SIP enhancements "bring multi-media capability and mobility for enterprise and carrier applications. TR/87 and ECMA-269 standardise new profiles tailored to SIP implementations, and specify a SIP transport mechanism for CSTA XML messages, new MIME types for CSTA, and illustrate CSTA/SIP deployment options. These enhancements complement existing SIP features to provide advanced call control and device control features for CSTA applications. New Voice Services in CSTA are based on Speech Application Language Tags (SALT) and provide speech services such as recognition, synthesis and speaker verification, extending existing mark-up languages such as HTML, XHTML, and XML."

Bibliographic Information

• Standard ECMA-269: Services for Computer Supported Telecommunications Applications (CSTA) Phase III. Ecma International. 6th edition. June 2004. 764 pages. Adopted as 6th Edition of Standard ECMA-269 by the General Assembly of June 2004.

  CSTA supports a complete set of standardized call control features:

  • Services: Accept, Alternate, Answer, Call Back, Call Back Message, Camp On, Clear Call, Clear Connection, Conference, Consultation, Deflect, Dial Digits, Directed Pick up, Group Pick Up, Hold, Intrude, Join, Make Call, Make Predictive Call, Park, Reconnect, Retrieve, Send Message, Single Step Conference, Single Step Transfer, Transfer.
  • Events: Bridged, Call Cleared, Conferenced, Connection Cleared, Delivered, Digits Dialed, Diverted, Established, Failed, Held, Network Capabilities Changed, Network Reached, Offered, Originated, Queued, Retrieved, Service Initiated, Transferred.

• Standard ECMA-348: Web Services Description Language (WSDL) for CSTA Phase III. Ecma International. 2nd edition. June 2004. 229 pages.

  "Web Services Description Language (WSDL) is an XML schema for describing Web services and how they can be accessed by Web based CSTA applications. Everything that an application needs to communicate with a Web service is described in a WSDL document.

  This Standard specifies a WSDL for the XML messages defined in ECMA-323, XML Protocol for Computer Supported Telecommunications Applications (CSTA) Phase III. All CSTA features (e.g., services and events) specified in ECMA-269 and ECMA-323 are specified in this Standard. CSTA WSDL facilitates the creation and deployment of web based CSTA applications. For example, by using CSTA WSDL with many industry Web services development environments, a web services developer can access CSTA features provided by a CSTA implementation without knowing details of the network or underlying transport protocols.

  The WSDL specified in this Standard is defined with XML and XML Schema. One example transport illustrated in this Standard is SOAP over HTTP. This Standard builds upon the XML data types and message formats specified in ECMA-323.

  Although a WSDL document contains both abstract definitions (WSDL messages and port type elements) and concrete protocol specific definitions (WSDL bindings, ports, and service elements), this CSTA WSDL Standard specifies only the abstract definitions of a WSDL document. The concrete protocol specific definitions are implementation specific and are outside the scope of this Standard. This Standard builds upon the XML data types and message formats specified in ECMA-323..."

• Standard ECMA-323: XML Protocol for Computer Supported Telecommunications Applications (CSTA) Phase III. Ecma International. 3rd edition. June 2004. 530 pages.

  "This Standard specifies an XML protocol for the services described in ECMA-269, Services for Computer Supported Telecommunications Applications (CSTA) Phase III. This Standard provides an alternative to the ASN.1 based protocol specified in ECMA-285. WSDL Standard ECMA-348 refers to the XML message types specified in this Standard..."

From the Announcement

CSTA is a (Ecma, ETSI, and ISOI/IEC) Standard with an exhaustive feature set and a comprehensive call model. CSTA supports a range of application landscapes — from basic first party call control to advanced third party call control with the same standardised model. CSTA exposes advanced communication platform features to application developers without burdening them with underlying protocol specifics.

SIP enhancements bring multi-media capability and mobility for enterprise and carrier applications. TR/87 and ECMA-269 standardise new profiles tailored to SIP implementations, and specify a SIP transport mechanism for CSTA XML messages, new MIME types for CSTA, and illustrate CSTA/SIP deployment options. These enhancements complement existing SIP features to provide advanced call control and device control features for CSTA applications.

New Voice Services in CSTA are based on Speech Application Language Tags (SALT) and provide speech services such as recognition, synthesis and speaker verification, extending existing mark-up languages such as HTML, XHTML, and XML.

Further enhancements to ECMA-269 include profiles for SIP user agents, an Internet URI device format, Device ID character support for International Numbers, Media Class types to support IM, SMS and MMS, and a new User Model for increased User mobility. ECMA-269 also takes advantage of the Ecma Application Session services (ECMA-354) that defines session management primitives specified in XML schemata.

The new editions of ECMA-348 (CSTA Web Services Description Language) and ECMA-323 (XML Protocol for CSTA) are now fully aligned with the new edition of ECMA-269. Ecma Technical Report ECMA-TR/88 (Designing an Object Model for CSTA) is a new member in the CSTA suite, which facilitates robust and prompt application integration.

"Ecma has a vital role to play in bringing new technologies and techniques to the marketplace within a reasonable timeframe," noted Jan van den Beld, Ecma Secretary General, "Rapidly developed international standards for CSTA increase vendor-independence and interoperability for converged communications-intensive enterprises".

"CSTA continues to be enhanced to support new features, for example in SIP, providing a way to go from ISDN to VoIP in several steps, in each of which applications could run in a differently mixed environment. This avoids a breakpoint from ISDN to VoIP," noted Christian von Reventlow, Tenovis CTO, "Tenovis has successfully implemented the transport mechanism for CSTA messages, introduced in ECMA-TR/87 for controlling SIP User Agents, for other signalling protocols (ISDN and VoIP). Therefore Tenovis actively supports the standardization process of this technique, which is in accordance with existing and future Tenovis products."

"We are very excited to see SALT-based voice services being included into the new edition of ECMA-269," says Xuedong (XD) Huang, General Manager of the Microsoft Speech Platform Group. "We have included SALT and ECMA-323 in Microsoft Speech Server, officially available since April 2004. Through our joint development and early adopter programs over the past two years, though, we have found the SALT specification with ECMA-323 to be industrial strength and meet the most demanding needs for computer telephony integration and call center automation. The inclusion of SALT with the rest of CSTA is a logical next step to bring voice services en masse to the telecom industry."

"Siemens, an active contributor to CSTA standardization activities for many years, is very pleased that Ecma has approved these new CSTA enhancements. These most recent enhancements enable applications to take advantage of the latest technologies in communications — including advanced speech services, mobility, and SIP devices," noted Tom Miller, Principal Architect, Siemens Enterprise Networks, "TR/87 is important because it shows how CSTA and SIP standards can be used together to provide a robust, standards-based application interface for feature-rich SIP phones that can be deployed in Enterprise, Hosted, and Carrier environments. This in an important step in the evolution of the CSTA standards and it creates some exciting opportunities for products that implement them."

As an Ecma approved standard, ECMA-269 6th edition will now undergo "fast-tracking" in the International Standards Organizations (ISO) and International Electrotechnical Commission (IEC) Joint Technical Committee 1 (JTC 1). Ecma continues to enhance the CSTA standards.