The fundamental shift in technology can really be boiled down to a move toward computer networks and away from telephone networks. Also in the mix is the inclusion of wireless voice and data services that add another layer of complication.
Telephone networks started with Alexander Graham Bell and remained largely analog for most their century of dominance. Back when everyone had a telephone line and nobody knew what broadband meant, there was an effort to get the telephone system to do double duty as a means of voice communication and also computer communication via analog modems. This quickly hit its technical limit because the telephone network was designed for the human voice, which has a very low bandwidth requirement.
There was an effort to move to digital phone lines, called ISDN, but it was too little too late. Cable and DSL broadband offered much higher speeds at lower cost. Businesses ordered T1 and T3 lines, originally developed for digitizing phone lines and bundling them to save transmission costs between telco offices. These digital lines work just fine as point to point or dedicated Internet connections for data transmission. In fact, they’re still the most popular connectivity for small and medium businesses because of plunging prices and high reliability.
VoIP came out of the computer, not telephone, world. The IP stands for Internet Protocol, the most popular networking standard. Yes, it does say Internet protocol, but that doesn’t mean it is limited to the Internet. In fact, the Internet would have probably stayed an obscure academic network had it not been for the development of Ethernet as a way to connect computers and their peripherals.
The difference between telephone networks and computer networks is the difference between switched circuit networks and packet switched networks. Switched circuit networks, like the telephone network, actually switch connections to set up a private path for each phone call. This is bit like switching electrical circuits to power something as long as you need to use it. Packet switched networks are more like the US Mail. The network provides hard pathways to every destination. Each letter or packet gets where it is going by looking at the address for that individual packet and routing it accordingly.
VoIP is simply a way to send a set of packets in real time that are digitized pieces of a telephone conversation. Put them together end to end and the voice from the distant location is recreated. When it works well it sounds just like a telephone call, although you can also use a computer for two way conversations if it has a microphone and loudspeakers or earbuds.
Just like computers have struggled to press the century old telephone system into service for carrying data packets, computer networks have struggled with carrying sensitive voice packets on a system designed to reliably transfer data files even if parts had to be resent due to network errors. When VoIP goes bad, it sounds garbled and clips each side of the conversation. That’s a symptom of a network that isn’t optimized for real time voice packets that have to get through without error, jitter and time delay (latency).
The Internet is hit and miss when it comes to carrying VoIP telephony. If you have sufficient bandwidth and little congestion, you can experience a decent quality call. That’s especially true if cell phone call quality is what you are comparing to. If the Internet is having problems or getting congested, you may come to miss your old faithful landline.
Businesses that require optimal voice quality don’t use the Internet as their phone connection. Instead, they use private lines or MPLS networks that are engineered to support packet voice signals. You may hear this referred to as enterprise voice or enterprise VoIP, even though there is no Internet involved with the Internet protocol in this case.
Are you considering a move to VoIP with your next business telephone system upgrade? If so, be sure to understand the costs and tradeoffs with Internet vs non-Internet implementations. You can get that help along with pricing and availability for Enterprise VoIP telephony at no cost or obligation for serious business applications.