What is an IP telephone system?

In order to be able to use internet telephony (also known as IP telephony), customers require an IP telephone system. But what really are the distinguishing features of IP-enabled telephones and Internet telephony and what exactly is needed?

How IP telephony works

This special form of telephony that makes use of the internet and fixed network and telephone lines. Internet telephony makes it possible to set up calls to other IP telephones with a broadband connection, as well as to make calls to landlines and to be reachable from the fixed network. Certain switching devices and protocols such as SIP and VoIP are required to convert the voice data into packets that can be transmitted over the internet. IP telephone systems must therefore be SIP-enabled. The IP telephone system - often referred to as a VoIP telephone - is used to transmit voice via an internet connection such as DSL or VDSL. This type of telephony is free of charge in many cases and cheaper in others - as is the case with international calls.

This is what the IP telephone system does

There are several ways to use Voice over IP, for example via a SIP provider or a VoIP gateway. There are also differences in IP telephone systems. Most models are Windows-based, but there are also Linux-based versions. The IP-capable telephone enables VoIP calls with landlines, mobile phones and smartphones as well as softphones such as the PC. It usually supports the following functions:

  • Parking and holding calls
  • Caller ID
  • Telephone directories
  • Call switching
  • Video telephony (not always)
  • Set-up of multiple user accounts

Anyone who uses a SIP trunk for an IP telephone can assign several numbers in the company and use them as if they were a fixed network connection. The phone always keeps its number and behaves the same - regardless of whether you connect it in the office, at home, on the road or in another country.

If you want to use the IP telephone system for a call, you have to register with the provider. This establishes the connection and sets up the call. If it is terminated, the connection is closed again. A directory is integrated in the company’s telephone system where all telephones or users with their respective SIP addresses are listed. Thanks to this storage, internal calls can be made and outgoing calls can be forwarded. In addition to the telephone system with SIP protocol, a router is required to establish the broadband connection for phoning over the internet.

Do you want to learn more about our cloud-based IP-enabled phone? Then we would like to inform you about our Cloud telephone system and its advantages!

Consulting & implementation

Your IP phone connection

Unified Communication and Collaboration (UCC)


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