VoIP consists of 2 major technologies....
Making Calls Over the Internet--Residential
This is the most common use of VoIP. It is also called VoIP lines or trunks. If you have a high speed internet connection, like cable modem, DSL, or T1, you can use your high speed connection to make phone calls on the internet. There are many companies like Vonage, Lingo, and VoiceWing (Verizon) that offer VoIP lines. Cable companies also offer VoIP lines, but only if you have their cable modem service. So, to boil it down, instead of getting your dial tone from Verizon over the traditional phone network, you get your dial done from your internet company.
Any phone system made (even an old one) can take advantage of VoIP lines. You do not need an IP based (IP PBX) or even IP compatible phone system. This is one of the biggest misconcetions about VoIP.
The advantage of VoIP lines are:
Lower Bills. Usually you pay a flat monthly rate and all your calls in the USA and Canada are free
You can take your number with you. If you move around the corner or across the country with VoIP you can keep your existing phone number even if you move to a different area code.
Multiple area codes. You can get phone numbers from different area codes or even overseas numbers.
Portability. You can move the VoIP router with you and take your service easily with you. You can even set it up to use your laptop with a virtual soft-phone and a WiFi connections to make calls from anywhere you can get high speed internet access.
Features. VoIP lines come with Caller ID, Call Forwarding, and lots of other great features.
The problems with VoIP lines are:
Quality is not as good as traditional phone service, but it's close and getting better all the time.
Set up can be very challenging, especially if you are planning on using your own router.
Depending on how fast your internet connection is, it may be possible to make several calls at the same time over the internet. However, the more calls you make at once the slower your internet connection will be and the poorer the sound quality of your calls will be.
Faxes, modem, and alarm systems don't work well over VoIP lines. Sometimes they won't work at all.
If you need a lot of lines, you may need more then one high speed connection, so the cost of the high speed internet connection may outweigh the savings.
There are some minor technical issue using VoIP lines and Automated Attendants and Voice Mail systems.
If your internet access goes down, all your phone lines go down too.
VoIP lines normally don't work if the power does out, but you can set up back up batteries.
Right now the Government does not tax VoIP service. If that changes VoIP may not be price effective anymore.
Making Calls Over the Internet--Business
Business class VoIP works in much the same way as for residential VoIP with one major difference. With business class VoIP a T1 is usually delivered to your office that provides both VoIP voice lines and Internet service. This means that your VoIP provider and your ISP are the same company This distinction is very important once you need more then 3 or 4 lines. Since your Internet connection is coming from the VoIP phone company problems such as latency, jitter, and static are greatly reduced.
Basically, your call has to travel a shorter distance. With residential, your call goes from Verizon DSL or Comcast Cable, to Vonage, to the person your calling. That's 3 steps or hops and problems can occur anywhere along with way. With business class VoIP, the 1st 2 hops are the same provider so things work better and you can get more calls on the same Internet connection.
Business class VoIP also has the advantage of being dynamically allocated. This means that when fewer people are on the phones, the Internet speed is faster. Voice always gets priority, so phone lines are always available. Packages are available from 5 to 105 lines or more and may come with unlimited calling or a large allotment of included minutes.
Business service is far more important then residential, so it's vital that you choose the right carrier. There are several major carriers like Verizon and Sprint and many smaller national carrier that you've probably never heard of. There are even more regional carriers that only service a small area and even more resellers that just package someone else's service. Let the experts at Teleco http://www.teleco4.com help you navigate through the maze of carriers and offers.
Connection Remote Workers or Remote Offices....Voice over IP Stations.
This is the 2nd major use of VoIP. You can "connect" to your office phone system from anywhere there is a high speed internet connection. Using a special VoIP telephone or a Laptop "soft phone" you can work from home or a hotel and it's just like being in your office. You have access to all your phone system features including the intercom, paging, all outside lines, voice mail, and even your extension can ring on your VoIP phone. Best of all, you don't lose the use of your computer. 1 high speed internet connection can run your VoIP phone and your PC at the same time.
With this same technology, you can link multiple office together into one seamless phone system. You can even share lines or the one voice mail system. You can even run your entire phone system over your office LAN or WAN without separate voice wiring (often called Pure IP or IP Based telephone systems), though that is very expensive and complicated and is best suited for very large companies with full time IT staffs.
Voice over IP is very exciting and more and more people are using it everyday. Let the experts at Teleco http://www.teleco4.com help you understand if VoIP is right for you. Voice over IP is available on both the NEC IPK and Toshiba CTX digital telephone systems.
10+ Years in Sales, Service, and Technical Programming of PBX and Key Business Telephone Systems