uaCSTA connection

What is uaCSTA?

UaCSTA is the abbreviation for User Agent Computer Supported Telecommunications Applications, and is a standard that enables Computer Technology Integration (CTI). The Computer Supported Telecommunications Applications (CSTA) protocol serves as the interface for smart connections between computer programs and telephone systems.

Using a CSTA server, the user can access and control an integrated phone from a CTI application installed on a personal computer (PC) or a laptop. The CSTA interface provides services such as answering, transferring, holding, and retrieving calls. It allows dedicated control and monitoring for all phone lines that are connected to the computer.

The CSTA protocol defines the data to be transmitted and the messages to be exchanged between the telephone system and the computer. It can operate serially via digital ISDN (Integrated Services Digital Network) or the data can be transferred via Transmission Control Protocol/Internet Protocol (TCP/IP).

What is CTI?

Computer Telephony Integration (CTI) is a technology that enables synchronised integration between a laptop or personal computer and a telephone. It allows computer software such as email applications to connect the user directly to the telephone system, with call functions just a click away, and to control the phone from his computer. NFON’s CTI solutions that provide this type of integration include NCTI Standard, NCTI Premium and NCTI Pro.

CTI and CSTA: How can uaCSTA aid your business?

If a user’s computer as well as the phone system is running uaCSTA-compatible software, they will be able to exchange information with each other, allowing them to perform the functions required for Computer Telephony Integration (CTI). Some email applications include features that work with CTI – for example, features enabling users to make phone calls directly from their emails, or to save notes related to the contact or conversation for future reference.

CSTA interface transmissions allow CTI compatible solutions without increasing the complexity of the software, while also helping to avoid performance bottlenecks, code size problems or any other overheads.

NFON’s CTI solution, NCTI, is designed to sit on top of cloud telephone system, Cloudya. It complements Cloudya’s many communication and collaboration features – one number, one inbox, meet & share and more – with deep business process integration. This gives organisations complete freedom in choosing their preferred communication devices and environments.

NCTI is available in three different options, Standard, Premium and Pro, to cover various integration needs. From data-read integration that gives call centre employees a full view of all relevant customer information to deep process integration with Customer Relationship Management (CRM) solutions and Unified Communications (UC) features such as interactive chats and video calls, NCTI made by NFON is flexible enough to adapt to every organisation’s needs. The combination of Cloudya and NCTI helps businesses maximise productivity and efficiency, and facilitates seamless communication from anywhere. It creates a communication process that is independent of expensive tools and free of geographical limitations – all in one single, user-friendly interface.

No overcomplicated processes, just simplicity. Simply plug in one device and all your connected devices are only a click away.


Further information


CTI is the abbreviation for the technical term Computer Telephony Integration. It refers to a communications solution that, with the assistance of computer software, allows functions of the phone…

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The acronym TCP/IP stands for Transmission Control Protocol/Internet Protocol and refers to a family of network protocols which are the basis for communication and data exchange over the internet as…

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