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[Write to us](/gb/request-information "Write to us") ### Internet telephony [What is the difference between Internet Telephony and Voice over IP?](/gb/get-started/cloud-telephony/lexicon/knowledge-base-detail/internet-telephony#section-3) [How does an Internet Phone System Work?](/gb/get-started/cloud-telephony/lexicon/knowledge-base-detail/internet-telephony#section-4) [How is Internet Phone Data Handled Securely?](/gb/get-started/cloud-telephony/lexicon/knowledge-base-detail/internet-telephony#section-5) [What is the Difference Between Internet-based and Traditional Phone Calls?](/gb/get-started/cloud-telephony/lexicon/knowledge-base-detail/internet-telephony#section-6) [Can You Call External Numbers / Regular Phones with VoIP?](/gb/get-started/cloud-telephony/lexicon/knowledge-base-detail/internet-telephony#section-7) [How does this work?](/gb/get-started/cloud-telephony/lexicon/knowledge-base-detail/internet-telephony#section-8) [What Options are There for Using VoIP?](/gb/get-started/cloud-telephony/lexicon/knowledge-base-detail/internet-telephony#section-9) [Convert a Conventional Phone to VoIP with an ATA](/gb/get-started/cloud-telephony/lexicon/knowledge-base-detail/internet-telephony#section-10) [What are the Advantages of Internet Phone Systems for businesses?](/gb/get-started/cloud-telephony/lexicon/knowledge-base-detail/internet-telephony#section-11) [What are Typical Business Use Cases of an Internet Phone System?](/gb/get-started/cloud-telephony/lexicon/knowledge-base-detail/internet-telephony#section-12) [How Do You Migrate From Traditional Phone Systems to VoIP?](/gb/get-started/cloud-telephony/lexicon/knowledge-base-detail/internet-telephony#section-13) # Internet telephony **What is Internet Telephony?** Internet Telephony refers to all types of telephony services (including phone calls, fax, voicemail, video calls and other forms of communication) where calls and data are sent digitally over the Internet using the [Internet Protocol (IP)](/gb/get-started/cloud-telephony/lexicon/knowledge-base-detail/ip-address), rather than being transmitted over traditional analogue landlines. An example of an Internet Telephony service is [Cloudya, the Cloud Telephone System from NFON.](/gb/gb/products/cloudya) ### What is the difference between Internet Telephony and Voice over IP? Internet Telephony and [Voice over IP (VoIP)](/gb/get-started/cloud-telephony/lexicon/knowledge-base-detail/voice-over-ip) are often used synonymously, but in reality, VoIP is a subset of Internet Telephony that refers to voice traffic only. While Internet Telephony is a general term for the IP packet-switching technology used by Internet phone systems to exchange any type of information, Voice over IP is the specific method for carrying voice calls over an IP network. Internet Telephony includes VoIP capability as well as a host of other features and functionality. For example, with Internet Telephony from NFON, it is possible to integrate Unified Communications (UC) and fax solutions over [XCAPI](/gb/get-started/cloud-telephony/lexicon/knowledge-base-detail/xcapi). ### How does an Internet Phone System Work? In order to use an Internet phone system, it is necessary to have a VoIP solution such as the NFON Cloud Telephone System. As you speak through a microphone (laptop, mobile or headset) your voice - the audio signal - is digitised. This data is split into packets and given individual labels. Your call is made up of different packets of data. Each packet of data travels over the Internet to the recipient. When the data arrives at the end destination it is put back into the correct order. The data is then converted into audio and the recipient hears what you said. Interestingly, the data packets don’t necessarily arrive in the order they were sent: they can overtake each other en route. When then arrive they are reassembled in the correct order and your message can be heard by the recipient. ### How is Internet Phone Data Handled Securely? When you send data over the Internet, it is usually sent over a server. Whether email or document storage, your data is stored or sent from the server of the service you are using. This is the same with the NFON Cloud Telephone System. Your data is hosted on secure, geo redundant, inland data centres. Our servers comply with the EU Electronic Communications law and meet the highest standards of data security, system availability, accounting precision, and many more. NFON data centres have been certified according to ISO/IEC 27001 – Information Security Management. ### What is the Difference Between Internet-based and Traditional Phone Calls? Voice over IP uses the Internet Protocol to make phone calls. Traditionally, phone calls were made over the PSTN (Public Switched Telephone Network). Originally the PSTN was fixed-line analog network. Now, however, the PSTN network is mainly digital. It refers to a mix of telephone lines, fibre optic cables and cellular networks and undersea cables. The key difference between PSTN and VoIP is that the PSTN is circuit-switched network. This means a dedicated channel is established for the duration of the phone call. VoIP uses the Internet Protocol (IP). With VoIP calls, a fixed line is not established. Instead, data packets are routed between the IP addresses of the caller and the recipient. This means data is sent according to the most efficient route and individual data packets may travel over different nodes of the network. VoIP takes advantage of the existing architecture of the Internet. As no fixed channel needs to be established it is much more cost effective than traditional telephony. ### Can You Call External Numbers / Regular Phones with VoIP? Most VoIP solutions allows you to call non-VoIP users whether they use mobile or landline connections. This means you can enjoy the benefits of VoIP and still connect with non VoIP users. ### How does this work? This is accomplished over a VoIP gateway. This gateway connects the VoIP system to the PSTN network. Likewise this connection makes it possible for PSTN users (landline) to call VoIP numbers. This is handled automatically by VoIP solutions, making calling non-VoIP users simple. ### What Options are There for Using VoIP? There are four main options for using VoIP: Install VoIP Software on Laptop/PC The first option is to install a VoIP client on your laptop or PC. This enables you to turn your computer into a VoIP-ready device. Audio is captured through the microphone and played through the speakers. Additionally, VoIP clients often include additional functionality such as instant messaging and video calls. No hardware is required for this setup. Use VoIP-enabled End Devices Secondly, it is possible to use specific VoIP-enabled end devices as well as IP and SIP telephones. These differ from standard telephones in terms of the technology that enables the data transfer over the internet. These types of phones usually have an ethernet connection that plugs into your modem or router. ### Convert a Conventional Phone to VoIP with an ATA It’s also possible to convert your conventional landline connection to VoIP. This is done by using a special Analog Telephone Adapter (ATA). This adapter connects your phone line to your modem or router and digitises your analog phone call. This lets you use your normal phone to make VoIP calls. ### What are the Advantages of Internet Phone Systems for businesses? Internet Telephony offers many advantages compared to traditional telephony as it makes business communication smarter, more flexible, more comfortable and more cost effective. One of its main benefits is that is allows multiple device integration including smartphones and desk phones. Users can, for instance, access their office extension from their smartphone, giving them complete freedom of communication, no matter whether they are working remotely or in the office. 1. **Full scalability and flexibility:** The best Internet Telephony solutions are hosted in the cloud, so there’s no need for the customer to buy, install and maintain expensive on-premise platforms. Implementation is quick and telephony services, the number of users and any extra features can be scaled up and down as required. 2. **Lower costs**: Typically, IP Telephony is more cost-efficient than traditional landline and mobile telephony. With a cloud telephony solution, internal calls within an organisation are completely free of charge. 3. **Seamless accessibility and portability**: Users can access their Internet Telephony services from anywhere and from any device as long as they have an Internet connection. A dedicated app – such as the Cloudya app from NFON – brings all the functionality of the cloud telephone system onto users’ smartphones, from voicemail and contact lists to call forwarding and conference calls. This makes the switch to mobile working easy. 4. **Advanced features**: With Internet Telephony, voice and data are transported over the same network, making new services possible – such as ‘meet and share’ video calls. Integrations add extra functionality, allowing organisations to streamline all their communication and business processes. For example, Cloudya from NFON integrates with Unified Communications tools such as [Microsoft Teams](/gb/en/integrations/msteams) for effective team collaboration. 5. **Excellent voice quality**: IP Telephony has come a long way since it was first introduced in the 1990s. As long as the user has a fast and stable Internet connection with good [bandwidth](/gb/get-started/cloud-telephony/lexicon/knowledge-base-detail/bandwidth), VoIP calls should experience no latency issues or interruptions. In addition, the latest [IP phones](/gb/get-started/cloud-telephony/lexicon/knowledge-base-detail/ip-phone) and headsets are designed to achieve superior sound quality with noise-cancelling and advanced audio compression, cutting out any background noise. ### What are Typical Business Use Cases of an Internet Phone System? 1. **Calls Within the Company**: NFON Cloud Telephone System provides the functionality of a traditional internal company phone network without any of the disadvantages. There is no need for expensive hardware installation or a costly service provider. Instead all of this is made possible over the Internet and our cloud system. Additionally, calls within the company are entirely free. This includes calls between different offices, even between branches in different countries. 2. **Calls to an External Company or External Mobile**: Cloudya,  NFON´s  Cloud Telephone System allows you to make VoIP calls to external company numbers (landline or mobile). This means you can enjoy all the benefits of VoIP calling and still connect with non-VoIP users. 3. **Use Your Smartphone as an Extension**: By connecting your smartphone to the Cloudya, you can use VoIP right from your mobile. This is done by downloading the Cloudya app in your phone. In a few simple clicks, you have all the functionality of the NFON Cloud System right from your mobile phone. Whether sat at your desk or out on the road with your smartphone, you have one universal number where people can reach you. ### How Do You Migrate From Traditional Phone Systems to VoIP? All you need is a reliable internet connection. VoIP / Internet phone solutions such as NFON take care of the rest. There is no tricky setup or installation on your computer as everything is hosted on our secure servers.  Further Resources: ### Related Articles ### Softphones **What is a softphone?** Softphones are like virtual phones: they are software programs that allow you to make [voice-over internet protocol (VoIP)](/gb/get-started/cloud-telephony/lexicon/knowledge-base-detail/voice-over-ip) calls over the Internet. This software can be installed on a PC, laptop, or mobile device. You can talk through a pair of headphones or from speaker phone on whatever device you have on hand. The user interface looks like a phone screen on a mobile phone, including controls like starting and ending the call and accessing the contacts list. There are several programs that provide users with virtual phones: * Cloudya, NFON’s [Cloud Telephone System](https://web-production.nfon.com/gb/products/cloudya) * [Nvoice for Microsoft teams](https://web-production.nfon.com/gb/products/integrations/microsoft-teams) [Softphones](/gb/get-started/cloud-telephony/lexicon/knowledge-base-detail/softphones) ### Voice over Internet Protocol (VoIP) **What is VoIP?** The **Voice over Internet Protocol,** also called IP telephony, is a method of communication for making calls over a broadband Internet connection as an alternative to regular calls made over an analogue phone using the [PSTN](/gb/get-started/cloud-telephony/lexicon/knowledge-base-detail/pstn). These VoIP calls can happen entirely over the Internet but where required, gateways also link to the PSTN. This means that VoIP users can still connect to anyone with a telephone number including local, mobile, and international numbers. VoIP services can be accessed from a computer with a so-called [softphone,](/gb/get-started/cloud-telephony/lexicon/knowledge-base-detail/softphones) from an IP phone, from a smartphone or from a conventional landline phone that is connected to a VoIP adapter. [Voice over Internet Protocol (VoIP)](/gb/get-started/cloud-telephony/lexicon/knowledge-base-detail/voice-over-ip) ### 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)](/gb/get-started/cloud-telephony/lexicon/knowledge-base-detail/tcp-ip). [uaCSTA connection](/gb/get-started/cloud-telephony/lexicon/knowledge-base-detail/uacsta-connection) ### Software as a Service (SaaS) Software as a Service provides users with access to software that is installed on a network and does not need to be installed locally. Like Platform as a Service (PaaS) or Infrastructure as a Service (IaaS), Software as a Service (SaaS) is a subdomain of cloud computing. The software is operated on the premises of an external [provider](/gb/get-started/cloud-telephony/lexicon/knowledge-base-detail/telephone-provider). Users require an [Internet connection](/gb/get-started/cloud-telephony/lexicon/knowledge-base-detail/internet-connection) and a local computer client. In many cases, the software can be called up and run directly via the web browser. Software as a Service is not based on the traditional licensing model that allows users to purchase software along with the right of use. As the service recipient no longer needs to operate the software himself, a usage-dependent or time-dependent licensing model generally applies. 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