Voice-over-IP — Advantages

Free telephone calls

One of the most noticeable advantages of VoIP solutions are rate free telephone calls between VoIP users where only IP access costs apply. One minute of IP telephony generates less than 1.2 MB of IP traffic; if voice compression is used this value is even five to eight times lower. This results in low rates for phone calls, especially for national and international calls. If using an IP flat-rate Internet tariff, no volume-based costs apply. In that case, VoIP calls are really free.

Obviously not all telephone users are directly reachable with VoIP calls. There are several solutions to interconnect the VoIP network with the plain old telephone network. Modern VoIP telephone systems have integrated telephony gateways to interconnect both worlds of telephony. In that case users that are not reachable with VoIP are called via the gateway with a standard telephone call, to standard rates. Another possibility is to rely on VoIP service providers, which offer one or several telephone numbers for rent. Every telephone user can reach these numbers; calls are diverted to corresponding VoIP phones or systems. The VoIP user can call standard telephone numbers by using a centralised gateway of the service provider, usually to cheap rates. Besides the Internet connection, no further telephone line is needed.

While in Germany the state office of telecommunications is limiting the sales of numbers to numbers of the region where the user lives, VoIP service providers abroad are often not restricted in that way. Renting a number from the New York region for example can be a solution if you want to be reachable for your American customers easily.

Global connectivity

Different to a standard telephone line, a VoIP connection is not limited to a given place. VoIP users can take advantage of the world-wide deployment of the Internet; it is possible from virtually any given place to connect your VoIP phone with your enterprise VoIP telephone system. Nobody calling you can spot the place your at, if you are in your office, in a hotel room, in your home office or if you visit a subsidiary.

Compared to mobile telephony systems like GSM or UMTS, the low cost of VoIP calls is appealing. If you cant use a VoIP telephone, you can use your notebook or your PDA with a soft phone.

Advanced functionality

In difference to classic telephony systems VoIP solutions benefits from using modern IT server technology. The hardware is conforming to industry standards and is affordable, efficient, and scaleable. With open standards like SIP, software base switching systems can be build which are easy to upgrade and cheap to maintain. The fitness for the future is way ahead of classical hardware based telephony systems.

Modular applications like voice mail systems, integration into central directory services, operation and administration with a web interface are standard with VoIP equipment while being additional and often expensive add-ons for telephony systems.

Integration into IT infrastructure

The utilisation of the Internet Protocol (IP) for the transmission of telephone calls allows not only the integration of computer networks and telephony, but offers the integration in modern business applications. The integration of computer systems and telephony for example (Computer Telephony Integration, CTI) can be implemented with software only, no additional interface cards or telephones with interfaces are needed. Modern applications like messaging systems or contact management systems can benefit directly from this technology, while other applications like enterprise resource planning (ERP) or customer relationship management systems (CRM) often provide interfaces for integration.

Future-proof technology

It becomes obvious that VoIP technology will dominate the analogue and digital telephony in the near future. The number of broadband Internet access customers in Europe is raising steadily, the volume of Internet traffic is growing exponential since decades. For backbone networks that interconnect different carriers, IP is currently the dominating transport protocol. IP is well suited to transmit different types of information, from technical communications to email, voice, video etc. For using IP, even high performance backbones can use standard components. IP as general transport protocol further eliminates the operation of different, concurrent transmission systems.

Further cost savings can be achieved by using VoIP technology for business or even at home. Current demands on high availability like making a telephony system redundant for failure resilience, low-price scalability, and high flexibility are easy to achieve with standard components while proprietary hardware-based systems like classical telephone switches fail at these requirements.