ECMA International has announced the official publication of the ECMA-348 Standard, providing "the world's first complete call control web services specification." Web Services Description Language (WSDL) for CSTA Phase III defines a WSDL for the XML messages defined in ECMA-323. It "builds upon the XML data types and message formats specified in ECMA-323 second edition, supporting all CSTA features, e.g., services and events as specified in ECMA-269 (Services for Computer Supported Telecommunications Applications - CSTA) and in ECMA-323. CSTA provides a protocol independent abstraction layer for applications. It provides a consistent, standards-based messaging interface that can be used with basic first party call control based platforms as well as more complex third party call control (CTI) platforms, or a combination of both."

ECMA-323 XML Protocol for Computer Supported Telecommunications Applications (CSTA) Phase III consists of "a set of XML Schemas based upon the W3C XML Schema Language Recommendation; it extensible XML schemas for all of the categories of services defined in ECMA-269. Call control is just one category of services in ECMA-323. Examples of other categories of services are: capability exchange (feature discovery) services, call routing services, services to control a device (e.g., message waiting, writing to display, forwarding settings), and others."

ECMA International is "an industry association founded in 1961 and dedicated to the standardization of Information and Communication Technology (ICT) Systems. For over forty years ECMA has actively contributed to world-wide standardization in information technology and telecommunications. More than 335 ECMA Standards and 85 Technical Reports of high quality have been published, more than 40% of which have also been adopted as International Standards."

About Computer Supported Telecommunications Applications (CSTA) Services

CSTA Service Definition Model: "CSTA (call control) services specified in ECMA-269 are modeled as a request/response interaction. Typically, one entity requests that a particular operation be performed; the other entity attempts to perform the operation and responds to the requestor."

Request/Response Interactions: "CSTA services consist of the following types of request/response interactions: (1) Services which specify a response in case of success or failure. The protocol description for these services includes a response element that represents the success (i.e., positive acknowledgement). In case of service failure, a fault element is used to provide the failure information (i.e., negative acknowledgement). (2) Services which only specify a response in case of failure. The protocol description for these services do not include a response element. A fault element is used to provide the failure information (i.e., negative acknowledgement). For CSTA event reports, no response is generated..."

Request/Response Protocol Requirements: The XML Protocol for Computer Supported Telecommunications Applications (CSTA) Phase III Standard "specifies CSTA-specific XML-encoded content for messages that are sent across a CSTA Service boundary. Typically this CSTA-specific XML is enveloped by a request/response protocol that provides a mechanism for correlating a CSTA request with a CSTA response, manages faults, defines header information, etc. The XML Protocol Standard does not mandate that a specific request/response protocol be used. However, the XML Protocol Standard provides examples of how the CSTA-specific XML can be used with several industry request/response protocols and transports such as SOAP (Simple Object Access Protocol), HTTP, and TCP. [adapted from Standard ECMA-323]

Bibliographic Information and Overview

• Web Services Description Language (WSDL) for CSTA Phase III. Standard ECMA-348. June 2003. 178 pages.

  "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..." [adapted from the Scope statement]

• XML Protocol for Computer Supported Telecommunications Applications (CSTA) Phase III. Standard ECMA-323. Second Edition. December 2002. 480 pages. "Ecma-323 second edition specifies the application layer protocol (in XML-schema) for CSTA Phase III Services (Ecma-269 fifth edition) plus Protocol Implementation Conformance Statements (PICS).

  The document "provides an alternative protocol to the ASN.1 based protocol specified in ECMA-285. Clause 5 to clause 8 inclusive describes the concepts underlying the request/response model, application association, notation and service, and a description of the template used in this Standard. Clause 9 to clause 26 inclusive contains CSTA-specific protocol details and forms the main part of this Standard. Annex A specifies the PICS for this Standard. Examples of CSTA XML encodings are provided in annex B through annex G.

  ECMA-323 consists of a set of XML Schemas based upon the W3C XML Schema Language Recommendation. The Standard includes schemas for many categories of services defined in ECMA-269 (Services for Computer Supported Telecommunications Applications (CSTA) Phase III).

  Call control is just one category of services in ECMA-323. Examples of other categories of services are: capability exchange (feature discovery) services, call routing services, services to control a device (e.g. message waiting, writing to display, forwarding settings), and many others.

  CSTA provides a protocol independent abstraction layer for applications. It provides a consistent, standards-based messaging interface that can be used with basic 1st party call control based platforms as well as more complex 3rd party call control (CTI) platforms, or a combination of both (1st party call control with some additional 3rd party call control features).

  CSTA modeling and concepts are also compatible with many procedural and object models such as the SALT CallControl object, per chapter 3 of the SALT specification..." [adapted from the TR/85 document]

• Using ECMA-323 (CSTA XML) in a Voice Browser Environment. ECMA International Technical Report TR/85. December 2002. 38 pages.

  "Services for Computer Supported Telecommunications Applications are defined by Standard ECMA-269 and the XML Protocol for those services are defined by Standard ECMA-323.

  In many cases, applications require only a small subset of the features standardized in CSTA. In a voice browser environment, processing speech (not call control) is usually the major focus of the application. For example, from a CSTA feature perspective, an application may simply need to answer an incoming call and then later clear it. As these speech-centric applications evolve they can use additional, more advanced, features standardized by CSTA that are provided by CSTA-conformant communications platforms.

  Since ECMA-269 and ECMA-323 are relatively large standards (combined over 1100 pages), it is a challenge for application developers without prior knowledge of the CSTA standards to know where to find basic concepts that they need to understand in order to implement basic CSTA features.

  This TR illustrates how ECMA-323 can be used in a Voice Browser environment. These concepts illustrated in this TR can be applied to any Voice Browser environment that provides an XML-based read/write messaging interface (i.e. CSTA Service Boundary) that supports asynchronous events from a CSTA conformant communication platform. SALT enabled browsers that implement a ECMA-323 interface for call control using the SALT smex mechanism is an example of a browser with this capability. Throughout this TR the term 'ECMA-323 enabled voice browser' is used, in a generic sense, to refer to browser implementation that support a CSTA conformant ECMA-323 interface. Examples are provided that show how ECMA-323 can be used in several different environments such as SALT-enabled browsers and CCXML..."

  ECMA-323 Illustrative Examples: Examples of ECMA-323 XML messages in the context of voice browser usage scenarios include: (1) discovering the features supported by a telephony platform; (2) establishing a monitor on a device, i.e., listen for incoming calls; (3) notification of an inbound alerting connection; (4) answering an inbound connection, notification of a connected connection; (5) clearing a connection, notification of a cleared connection; (6) initiating an outbound call; (7) a single step transfer scenario; (8) a single step conference scenario..." [adapted from the Scope statement and Introduction]

• Services for Computer Supported Telecommunications Applications (CSTA) Phase III. Standard ECMA-269. Fifth Edition. December 2002. 688 pages.

  This Standard specifies the Services and Event Reports for Computer-Supported Telecommunications Applications, Phase III (CSTA). The fifth edition of Phase III Services for CSTA adds feature that: (1) enhance the ability to support non-voice media interactions such as Email, Instant Messaging, and Chat; (2) enhance the ability for CSTA applications to utilize SIP based features supported by underlying protocol layers; (3) enhance the ability to leverage CSTA Standards for Voice Browser applications by the addition of three new profiles.

  This Standard is focused on providing application service interfaces to a Switching Function, Computing Function and a Special Resource Function. A CSTA application interface is disassociated from the various user-network interfaces and network-network interfaces CSTA applications may serve, observe or manipulate. Because CSTA operates with existing telecommunications interfaces indirectly, it operates generically, so that differences among various existing interfaces are hidden from CSTA applications. Support of user-to-network interfaces is outside the scope of CSTA.

  Although most terminal equipment (TE) are suitable for use with CSTA there will be instances of TE that will not be suitable in certain circumstances. Examples are: (1) FAX terminals and modems that are unable to adjust their transmission modes to prevent carrier conflict when both parties are alerted via CSTA during call establishment; (2) Functional terminals that perform telecommunication functions outside the control of the Switching Function. Services defined in this Standard allow functional integration between a computing network and a telecommunications network. Computing platforms (i.e., Application Programming Interfaces - APIs) that support such functionally-integrated applications are outside the scope of this Standard. Communication between the computing and switching (i.e., telecommunications) networks may take place via intervening networks ranging from simple point-to-point connections to local- or wide-area telecommunications networks.

  This Standard is part of a suite of CSTA Standards and Technical Reports that provide a comprehensive description of the architectural and practical issues involved in applying, implementing, and utilizing CSTA-based CTI applications..." [adapted from the Scope statement]

From the Announcement

Ecma International announces the publication of several Computer Supported Telecommunications Applications (CSTA) standards, including the world's first complete call control Web Service specification, Ecma-348.

Web services are self-contained modular business applications that are loosely coupled, communicating directly with other Web services via the Internet using standards-based technologies. Web services can be accessed by customers, suppliers, and trading partners independent of hardware, operating system, or even programming environment.

Ecma-348 (CSTA-WDSL) provides a Web Services Description Language (WSDL) specification for CSTA. A WSDL is an XML schema describing everything that an application needs in order to communicate with a Web Service. Ecma-348 builds upon the features of Ecma-269, 5th edition -- CSTA Services and Ecma-323, 2nd edition -- CSTA XML Schema, which were published in December 2002.

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 December 2002 editions of the CSTA Standards enhance the support for non-voice media such as Instant Messaging, Email, SMS, etc. The new editions also provide more support for inter-working with SIP based infrastructures and include specific profiles that are optimized for voice browsers.

Additionally, Ecma TR/85 Using Ecma-323 (CSTA XML) in a Voice Browser Environment (December 2002) illustrates how voice browsers use CSTA call control. Examples of using CSTA XML with SALT browsers and CCXML browsers using ECMAScript are included.

Onno Elzinga, Ecma International Chief Technology Officer, commented: "Ecma-348 is the first complete Call Control Web Service specification. It enables the use of Integrated Software Development Environments, which are off the shelf tools, unlocking the vast potential of Web Services programmers already familiar with XML. It complements and uses the XML schema definitions of Ecma-323 and enables the use of other Internet Protocols such as SOAP, TCP and HTTP."

Victor Chan, Siemens Director OpenScape Product Management said: "The latest Ecma International CSTA Standards bring together all forms of media that people need to communicate in their business. CSTA lets our customers write applications that manage Voice, Instant Messaging, SMS, Paging, and Email, in the same way, no matter what type of infrastructure (IP based SIP, for example) they have. This is real voice and data convergence today."

Mr. Manfred Edelmann, Tenovis Senior Chief Architect said: "The new CSTA WSDL Standard and the existing CSTA XML Standard offers application developers a very comprehensive and powerful set of XML call control features. Applications can be developed much faster and with much less complexity because WSDL frees application developers from having to deal directly with underlying web transport protocols."

Dr. X.D. Huang, General Manager of the Speech Technologies group at Microsoft, said: "CSTA XML for Voice Browser Environment plays an important role in the Microsoft Speech Server, currently available to our beta program participants. Through the open Ecma standard, our partners are able to develop advanced communication services using the rich functionality provided by CSTA, and are able to do so in an interoperable and portable manner without having to resort to expensive and proprietary solutions."

Ecma continues to enhance the CSTA standards. It is currently working on advanced conferencing features to support collaboration applications, using CSTA with new versions of W3C Web Services/SOAP specifications, using CSTA with SIP phones, for example.

Since its inception in 1961, Ecma International (Ecma) has developed standards for information and communication technology (ICT) and consumer electronics (CE). Ecma is a not-for-profit industry association of technology developers, vendors and users. Industry and other experts work together in Ecma to complete standards. Ecma then submits the approved work for approval as ISO, ISO/IEC, and ETSI standards.

Ecma is the inventor and main practitioner of "fast tracking" of specifications through the standardization process in Global Standards Bodies like the ISO. In ISO/IEC JTC 1, Ecma has the status of an A-liaison, equivalent to a national body without voting rights. Since its start in 1987, over 196 (more than 80%) of the 232 submissions for fast-track processing in JTC-1 have come from Ecma.

Ecma's main areas of standardization include: Scripting and programming languages; Optical and Magnetic storage; High speed interconnects; Safety, Environmental, Acoustical and Electromagnetic product attributes; Enterprise and Proximity Communication and Networking; and File and Volume structures. Publications can be downloaded free of charge..."