What is the difference between VoIP and ISDN?

Until a few years ago, most people in the private and business sector relied on an analog connection or ISDN for the use of the internet. In the meantime, VoIP with SIP is gaining ground in the business sector. What is the difference between VoIP and ISDN and why is it worth switching?

ISDN as a reliable basic solution

ISDN replaces the analog connections as a digital communication mechanism. Not only does it offer a faster internet connection than the modem, but also a few more possibilities in terms of usage. Two connections can be used at the same time, so that you can surf the internet and make phone calls, for example. This is especially important in everyday business life. An ISDN connection is available everywhere in the country and can be used at low rates, with a data transmission rate of 64 kbps. And this is exactly where the weak points of the service come in. Although it is preferable to the modem and impresses with unlimited availability - and no possible loss of speed as with broadband internet with DSL due to too long lines - it offers speeds that are still not always high enough. Anyone who has to deal with large attachments and the uploading or downloading of large amounts of data in the course of their work or is dependent on live communication without interruptions should consider switching from ISDN to VoIP.

The technology of the future: VoIP and SIP

The biggest difference between VoIP and ISDN is the high speed of the broadband connection used. A VDSL connection or a fiber optic cable achieves high data transfer rates of 16 Mbps. On the basis of a broadband connection, VoIP (Voice over Internet Protocol) can be used for internet telephony. The connection and data transfer (of voice data) is established by means of special protocols such as SIP. You avoid the fixed network and rely on the server networks of the SIP providers, so that free calls are possible. In addition, you get significantly more flexibility.

A VoIP connection makes it possible to use several devices at the same time as well as several phone numbers. The cost savings on the part of the provider means cheaper calling expenses for the customer. Especially the virtual cooperation with employees or branches abroad profits from this. If you want to save as much money as possible, use your computer as a softphone instead of investing in a VoIP phone.

ISDN connections are rarely considered by providers and can hardly be expanded, supplemented or improved, whereas the full potential of Voice over IP is not yet exhausted and the solution has a high future potential. For many providers, the monthly basic price for VoIP is the same as that of the analog connection but still offers the same or even more options as ISDN.

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