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A brief explanation of technical terms.

Here you can find abbreviations, explanations and translations of technical terms from the estos world.

1st-Party – The Single-User Workplace

In single-user workplaces, there is usually a direct connection between the telephone and computer, which can also be achieved via LAN.

3rd-Party – The Network Solution

Within network solutions, the control and monitoring of phones and their assignment to users takes place centrally on a server, which generally has applications for easy administration as well as additional, intelligent services. These are the basics for team cooperation and thus create a significant added value compared to single-user solutions.

ProCall Enterprise

 has a very powerful and scalable 3rd-party CTI implementation with all VoIP, hybrid or traditional TDM telephone systems as long as their interfaces support CSTA or Microsoft TAPI.


All-IP is the conversion of the existing transmission technology in the telecommunications network to the internet protocol. The previously widespread ISDN transmission technology will then no longer be available in the public telecommunications network. However, this does not mean that companies can no longer use their ISDN-based PBXs: All that is required is to install a VoIP gateway between the PBX and PSTN. Internally, ISDN can still be used, for example, for interaction with the ixi-UMS Unified Messaging Server.

ASP (Application Service Provider)

The Application Service Provider (ASP) is a service provider that provides an application (e.g. an ERP system) for information exchange via a public network (e.g. internet) or via a private data network. The ASP deals with the entire administration, such as data backup, the installation of patches, etc. Unlike application hosting, part of the ASP service is also a service (e.g. customer support) around the application. Here the required software is not purchased but rented for use via the data network when required. With the aid of ASP services, companies can outsource entire administration sectors or process steps and thus focus on their core business.

CEBP (Communication Enabled Business Processes: Business Process Integration)

Communication Enabled Business Processes (CEBP) is the integration of communication functions into existing IT applications. This business process integration allows the processes of the value chain, which are already automated or supported by various leading applications such as CRM, ERP or other industry solutions, to be connected to communication processes in the company.

For example, information such as name, customer number and last orders from an ERP system are already displayed during an incoming telephone call. Functions such as taking an order can then be controlled directly in the ERP system during a call with just one click.

The advantages of business process integration include time savings, work simplification, error reduction, comfortable working and easier access to information. For a company, this is particularly evident in an improvement in productivity and an increase in customer and employee satisfaction.

For the analysis of an individual customer scenario in advance and the identification of suitable interfaces, estos offers accompanying technical services as professional services.


Depending on the available technical and administrative conditions, ProCall can be used to conduct chats in various variants.

  • TextChat: Exchange of text messages with notifications of Sent, Delivered, Read. Emojis can be used in conjunction
  • AudioChat
  • VideoChat


Collaboration describes the sum of various tools which are available for individuals within an organization to enable them to work optimally together. These tools, which allow workgroups or teams to work together, even when they operate separately in time or space, are named as collaboration tools or collaboration features. Examples would be functions such as writing e-mails, the mutual visibility of calendars, using wiki or blogs within the company. With ProCall Enterprise, estos offers numerous collaboration functions such as desktop sharing and audio/video chats.

CSTA (Computer Supported Telecommunications Applications)

CSTA is the abbreviation for Computer Supported Telecommunications Applications. This standardized protocol specification is used for data traffic between a telephone system and computer programs. Using this specification, 

ProCall Enterprise

 can interact with the various PBX systems.

CTI (Computer Telephony Integration)

Computer Telephony Integration (CTI) designates the connection between the telecommunication world (TC) and the world of information technology (IT). CTI allows calls to be established, received and ended automatically from computer programs. CTI also enables callback and the forwarding and mediation of calls as well as the establishing of conference calls. Typical CTI programs signal all statuses of telephone devices to the user, regardless of whether they are non-wireless or mobile devices.

The integration of the world of telecommunication (TC) with information technology (IT) can take place on different levels: integration of data services, integration on the application layer and in the user interfaces. The CTI viewpoint differentiates generally between two architectures, but mixed versions are also possible: 1st party CTI for the single-user workplace and 3rd party CTI for networked workplaces.


The ECSTA software from estos provides a TAPI interface as TSP (Telephony Service Provider). This middleware is used for data traffic between TC infrastructure with telephone systems, telephones, providers/cloud PBXs on the one hand and IT infrastructure with TAPI-capable communication applications such as UCServer, ProCall Enterprise or other TAPI applications on the other. Windows applications can work with different PBXs via ECSTA and provide CTI functions (Computer Telephony Integration), e.g. for the resolution of contact data from an ERP/CRM system during a call or for dialing from Microsoft Outlook contacts.

estos Business Partner

estos Business Partners have achieved the first level of certification within the framework of the partner program. With the successful completion of a 1-day workshop, including examination by an estos instructor or an authorized distribution partner (estos Competence Center), the respective employee of the company obtains the distinction of being an estos Business Partner (personal certification). The associated company is authorized to place the estos Business Partner logo on its website.

estos Competence Center

estos Competence Centers are distribution partners in Germany, Austria and Switzerland that have been specially awarded by estos. They have the Expert Partner status and are characterized by the fact that they regularly offer independent estos Business Partner workshops for their specialist dealers at their own locations. They always use the latest ProCall Enterprise, as well as ProCall Mobile and MetaDirectory versions and are contact partners for First Level requests from specialist dealers. They provide expert advice on all estos products, including all collaboration functions as well as the federation technology, to improve communication with resellers.

estos Expert Partner

estos Expert Partners have reached the second level of certification within the framework of the partner program. With the successful completion of the 2½ day training and having passed a certification test, the company employee obtains the distinction of being an estos Expert Partner (personal certification). The associated company is authorized to place the estos Expert Partner logo on its website. Expert Partners have experience in the marketing and provision of estos solutions and can individually solve problems and adapt to the specific requirements of customers.


The federation concept enables companies to network with suppliers, partners and customers beyond their own company boundaries on the basis of open standards and secure protocols. With regard to communication and teamwork, the basis is provided by the protocols SIP/SIMPLE and XMPP. With federation, networked servers, e.g. 

ProCall Enterprise

, Microsoft Lync, Cisco Jabber or IBM Sametime, can exchange information such as instant messages, presence or audio/video with each other. The instant message address is used as the address of the participant, which can be an SIP or XMPP address, for example, comparable to an e-mail address.

The benefit for users is comparable to e-mail with regard to addressing, however several types of media (multimedia) can be included in the communication. The necessary steps for the successful setup of a federation are comparable to the setup of an e-mail system.


H.323 is an ITU-defined standard for controlling real-time voice transmission and video conferencing over IP-based networks such as LAN, WAN or the internet. The ITU – International Telecommunication Union – is a specialized agency of the United Nations and deals officially and worldwide with technical aspects of telecommunications. ixi-UMS uses the H.323 standard to work together with IP-based telecommunications systems.

Home Office and Mobile Working

In times of smart working, more and more people are working from home. In the home office, technical conditions and access possibilities are different from those in the workplace.

ProCall Enterprise

offers many opportunities to stay in touch with colleagues and business partners, to communicate and work together easily from home.  Unified communications functions such as audio/video chat, group chat, screen sharing and softphone are helpful in this regard.

estos offers ProCall Mobility Services via


to companies that do not want to or cannot set up secure accessibility from outside the company's own network for connecting remote workstations themselves. These services facilitate the setup of mobile working and home office workstations. 

(IM) Instant Messaging

Instant Messaging (IM) is a method of communication that is characterized by short text messages. It is also colloquially called chat or chatting. With this method, two or more persons communicate with each other in real-time – without a noticeable time delay, comparable to a normal conversation. Chats are often used for an uncomplicated and quick exchange of information, where a prompt answer is helpful or necessary.

IVR (Interactive Voice Response)

Via an IVR system, companies can provide their customers/interested parties with uncomplicated and automated access to information. And this simply by telephone. By calling an IVR system, a telephone information system, the caller interactively receives the corresponding information, for example tariff information or the status of an order. The information is output to the caller dynamically and automatically according to predefined processes: depending on the choice of the caller, for example, a database query is executed in the server system for authentication or for searching for the appropriate order number. The caller does not require any special technical equipment other than a telephone.

How does IVR work with ixi-UMS Enterprise?

With the communication solution ixi-UMS from estos, companies have the possibility to set up automated information systems for telephone enquiries in addition to unified messaging. Depending on the technical equipment, the information can be transmitted not only by telephone, but also by fax, SMS or e-mail.

The basis for the realization of such an information system is VoxML.

LDAP (Lightweight Directory Access Protocol)

Lightweight Directory Access Protocol (LDAP) is a standard protocol for access to directories, e.g. to user management in Active Directory or IBM Domino. For example, ixi-UMS accesses the Active Directory via LDAP to validate authorizations. ProCall can take advantage of MetaDirectory via LDAP to synchronize and present data, for example to display contact data for incoming or missed calls. Unified availability via the LDAP protocol and database-independent format enhance the quick and clear presentation and processing of search results.


LiveChat by estos gives companies the opportunity to offer clients and potential customers direct contact on their own website. For this, interactive touchpoints are available with LiveChat: website widget, contact portal, multimedia business card. This ensures that employees of a company can be easily reached. LiveChat can take into account availability (presence status) or employee capacity. LiveChat can also be used, for example, to answer individual questions about products, customer service, video consulting, or to give further support. The main advantage of the LiveChat option is that the initial contact takes place without any additional plug-ins needed by the visitor and it works on-demand or with interest shown (pull principle) picking the visitors up at just the right point on their customer journey. Therefore, the customer has the choice of using the desired communication channel (text chat, video chat, telephone, e-mail) for making contact.

Load Balancing

Using load balancing, requests are distributed to multiple servers, which appear outwardly as a single server. If one of these servers fails, the other servers take over its task.


MetaDirectory is an LDAP server for fast access to contact data. It consolidates various databases into a single, company-wide, consistent LDAP directory. As a result, relevant data such as telephone numbers and other contact data are available to all employees. The intelligent processing of the data enables a simple search and the fast presentation of results – even with large data pools. ProCall and ixi-UMS can use the data prepared in MetaDirectory

MWI (Message Waiting Indication)

ixi-UMS unified messaging server supports MWI/Alert functions. The Message Waiting Indication signals incoming messages in the inbox with an info text, light key or a lamp on the telephone.

Partner Program

With the estos Partner Program, we focus on specialist dealers, system vendors and system integrators. On one hand, in-depth expertise in the area of unified communications & collaboration is established with the program. On the other hand, the estos team supports its partners through active sales support and materials for the marketing of its solutions. The estos Partner Program is structured in two stages. Training for estos Business Partners takes place in a 1-day workshop. In the second stage, certification for the estos Expert Partners takes place in a 2½ day training course. A requirement for participation in the program is registration as an estos reseller.

Presence Management

Presence is described as the status of a person or resource (e.g. a room), which can be: Available, Busy, Do not disturb or Absent. The presence helps to determine whether a contact can be reached at this moment or is engaged elsewhere. In this way, a form of communication best suited to the situation can be selected, e.g. instant messaging, telephone or e-mail.

In a professional presence management system, individual settings and the calendar status or the status of the telephone are included in the presence of a person, thus allowing even more accurate information on availability. If a contact is in a meeting, this is expressed in the presence by "busy – in a meeting", for example. In addition, further information is specified at the time of availability. More Info about Presence Management.

PSLA (Premium Service Level Agreement)

Companies can conclude this PSLA contractual agreement with estos. The PSLA regulates services such as software assurance, software maintenance, access to estos service and support and accompanying technical services for the purchased product licenses within the terms of the contract.

Remote Office (One Number Concept)

The Remote Office Function is a possibility for mobile ProCall subscribers to initiate calls via their business telephone outside the company's own network and without the need for a telephone at the workplace. In the so-called One Number Concept, the business telephone number is signaled to the participant called. This means that business calls can be made from any telephone such as a private smartphone or from home using the "Remote Office" phone number, or incoming calls to the business number can be automatically forwarded to the "Remote Office" phone number.

Reverse Search

Reverse search, inverse search or CLIP search refers to a search process where contact details (e.g. name, address, customer data, order status) linked to a call number or internet address are searched for.

For a complete reverse search, comprehensive contact databases must be used. These contact databases are generally telephone directories, directory services (e.g. LDAP, Microsoft Active Directory) or CRM/ERP and industry solutions. This contact data is often available with different degrees of quality, i.e. the data saved cannot always be programmatically evaluated in the original. For example,  MetaDirectory is then used here. MetaDirectory collects data from different databases and processes it so that a reverse search is possible. 

In combination with ProCall Enterprise, the search settings can be further adapted – for example, so that if no direct match is found, the last 2 or 3 digits of the telephone number are removed and replaced with a 0. The suitable possibilities are sorted and displayed according to the probability of a match. In this way, even callers who call from an extension in a large company can be identified. This so-called "company search" provides an even higher degree of match accuracy.

Screen Sharing

Depending on the available technical and administrative conditions, call partners can use ProCall to enable their opposite number to view their own screens and, if necessary, allow control via mouse and keyboard. So, for example, you can view or work on a document together, even when you are not in the office. Telephone calls, audio chats or video chats can take place in parallel with your call partners. The relevant authorization between each other is necessary for this and can be given administratively.

SIP (Session Initiation Protocol)

SIP is a standard developed by the IETF – Internet Engineering Task Force – for a signalling protocol that can establish, modify and end sessions with two or more participants. ixi-UMS uses the standard protocol SIP to work together with IP-based PBXs.

SLA (Service Level Agreement)

SLA stands for the estos Service Level Agreement. Companies can conclude this contractual agreement with estos. The SLA regulates the access to estos service and support and accompanying technical services for the purchased product licenses within the  term of the contract.


SoftFax, Fax Passthrough or G.711 Clear Channel, is a method for transmitting fax messages in IP-based networks. The fax message is transmitted here as an audio data stream between the fax server and PBX. SoftFax works with the G.711 passthrough method. G.711 is an ITU-T guideline for digitizing analog audio signals.


T.38 is a protocol described by ITU-T for the transmission of fax messages via VoIP connections. The messages or fax information are not transmitted between the fax server and IP-PBX as audio data, as in the conventional telephone network, but are packaged as pixel data according to the IP network protocol. 

TAPI (Telephony Application Programming Interface)

TAPI is a Microsoft-developed programming interface for telephony applications. ProCall uses TAPI to interoperate with PBXs. 


With UCConnect, estos facilitates the setup of

ProCall Enterprise

functions that go beyond the company's internal network. This includes mobile working on the move or connection via home office as well as communication via websites including audio/video chat. On the cloud platform UCConnect developed for this purpose, companies can use the online services with few resources and little technical know-how. UCConnect not only facilitates setup, but also reduces adaptations to the customer infrastructure. estos divides UCConnect into two hybrid cloud components. ProCall Web Communication Services support companies in implementing the contact portal and the multimedia business card in ProCall Enterprise. The ProCall Mobility Services facilitate the setup for mobile work and home office workstations. With the ProCall Mobile Apps or from the home office, users access unified communications features. These include, for example, presence management, important data on business contacts, video chat or the integration of softphone functions.


UCServer is the essential server software component for ProCall Enterprise. UCServer is responsible for controlling and accessing the Real Time Communications services like audio/video, softphone and CTI as well as the presence, instant messaging and journalling services and the associated contact and calendar data. It manages the administration of users and offers security through authentication and authorization management. UCServer keeps log data and journals and central databases are connected.  

In addition to an already existing software administration, UCServer offers, methods for the automatic, central installation of workstations. 

Unified Communications

Unified Communications (UC) applications make communication in companies more effective. They optimize users' workflow by minimizing errors, making recurring tasks easier and simplifying collaboration within a team as well as with business partners. With this, Unified Communications incorporates the central idea of computer telephony (simply dial/dial assistance, Click2Click) and transfers it (Gartner, the market researcher, calls it "reducing the human latency") to other media such as e-mail, instant messaging, desktop sharing and video communication.

In contrast to a traditional CTI solution that is structured with a telephone line at the center, the latest generation of unified communications software is based on a person-oriented architecture. This places the focus on the communication partner – the dialog partner.

This principle, driven by SIP technologies, is just as decisive for a successful implementation of a unified communications strategy in companies in the long-term as the perfect interaction with their existing ITC infrastructure.

Background: The convergence of telephony technologies (Voice over IP) is joined by a convergence of software applications on the PC workplace. Modern internet-oriented protocols such as SIP accelerate this process. Its aim is to allow individuals, teams and organizations to handle their tasks faster and more efficiently. As a result, traditional CTI appears to be fading into the background, but is gaining significance under the surface as it now enhances almost all communication-oriented business applications with the component of telephony.

The traditional CTI application "dial assistance" has turned into a suite of applications on the subject of unified communications. In addition to CTI and presence management, this also includes instant messaging services that have won recognition for fast, confidential communication with colleagues, customers and partners, even when compared with e-mails – as well as desktop sharing and video communication. The user gains an overview and monitors the differentiated events at the workplace from individual interfaces which can be designed for an optimum workflow. Transparency prevails on the server side. Otherwise, the need for integration with other applications would not be covered.

Unified Messaging

With unified messaging, incoming and outgoing messages are processed and brought into a uniform form. The typical Unified Messaging System (UMS) features fax, voice and SMS are typically deployed and handled through a single, integrated, server-based platform.

This allows users to manage all types of messages under one surface – directly at their workstation or on the move: on a PC, tablet or mobile device. Sending and receiving faxes, voice-mails and SMS text messages are done in the usual e-mail client such as Microsoft Outlook or IBM Notes.  

VideoChat (Communication, Video Consulting and Video Authentication)

VideoChat is one of the essential communication functions in

ProCall Enterprise

and LiveChat. For the exchange of information, VideoChat comes very close to personal contact, because the participants can not only hear each other, but also see each other and perceive the facial expressions and gestures of the other party. 

Audio/video communication with ProCall is based on the WebRTC standard and is specially designed for businesses.

In contrast to the use of services established for private use and possibly free of charge, with ProCall Enterprise, communication remains within the company and is appropriately secured. Via federation, the accessibility of partners can be extended to trusted networks even outside the company's own network.

For interested customers and clients, companies can be reached via LiveChat and the company's own websites by VideoChat, for example, to provide advice and support via video communication or to realize video authentication.

VoxML (Voice Extensible Markup Language)

As an XML-based description language, VoxML enables the webserver-based implementation of voice dialog applications e.g. for the realization of an IVR system based on ixi-UMS unified messaging server. ixi-UMS acts as a link between public telephone network and application logic. 


WebRTC is understood as several standardization initiatives combined by Google under the open source project for different standardization bodies for communication and collaboration in real-time on the internet (Real Time Communications or RTC). It enables the establishment of a direct connection (Peer-to-Peer or P2P) between two web browsers. This connection, on the other hand, enables the exchange of audio/video or other data in real-time. The standardization bodies are the IETF (Internet Engineering Task Force) and W3C (World Wide Web Consortium). WebRTC has the potential to dramatically transform our communication behavior as many barriers are brought down for users and programmers. In any case, webRTC accelerates the acceptance of audio/video communication as there is no need to use plug-ins or proprietary technologies. A compatible browser (Chrome, Mozilla), suitable camera and headset are enough.