Switching People to traditional phone service to VoIP (also known as Plain Old Telephone Service name or POTS) often questions about faxing with VoIP. Although it may seem obvious that faxes would work on a VoIP line in the same way they work on POTS line, the actual mechanism is much more complex and often difficult.
To understand the problem with the mixture of telephone lines VoIP and traditional fax machines, we need to understand how VoIP differs from POTS. Regarding the interference with the facsimile is, there are differences in two broad areas :. Switching and compression
Source: greg Westfall via flickr
switch A big difference between the two types of telephone service how they handle the "switching" or sending audio back and forth between the two parties in the appeal. A POTS line connects a call using a method called circuit switching. With circuit switching, the phone of the caller and the recipient's phone are connected in a continuous circuit, physical, meaning the voice signal is sent in a loop back and forth between phones throughout phone call . When talking on a telephone line POTS, your call takes up space on the timeline you essentially rent the son.
VoIP does not work that way. Instead, it leverages the same system used to load images and information when you surf the Internet on your computer: packet switching. Instead of establishing a single connection between two phones and send the signal continuously back, VoIP providers to cut the voice signal into small pieces called packets. They then attach a specific set of directions to each packet, indicating which recipient must obtain the packages and how to reassemble them, and release the packets in the network through your router. Packets trickle through the Internet individually, each taking the path of least resistance rather than to follow the same route each time. At the other end, a gateway, ATA, or IP phone (click here for more information on these terms) receives the packets, the constitution of a buffer before reassembling them into a voice signal and transmit them either on a POTS line to the recipient, or directly on the phone if they are received by an ATA or IP phone. If the system detects silence on one end or the other, it rejects these silent packets instead of sending them. This saves bandwidth by not using the network to send silent when a party is simply listening.
This system allows VOIP carriers to send calls using a minimum of data, which helps to reduce costs and make phone calls smoother. Since we can not hear the slight delay while the system disassembles and reassembles the speech signal, we usually do not detect defects in choppy or audio, even if the system loses a packet or two, which happens from time to time other.
A fax machine, however, a "hearing." When a very accurate machine sends a message, it does so by transmitting a solid patch of his detailed above voice line, the machine interprets the recipient to recreate the image or document. This patch may contain sound precisely calculated segments of silence, and very fine modulations. When the VoIP system cuts the packet signal to send, it can distort or lose packets, which will cause the fax to fail.
Compression: The second major category of fax failures with VoIP systems are those related to compression. VoIP systems use codec, called codecs to compress the audio signal of your call for efficient transmission over the Internet. The codec samples the audio signal, pulling a small piece on several thousand times per second. Depending on the codec, the system may sample the noise of 64,000 times per second, 32,000 times per second, or 8000 times per second. Many VoIP systems use a G.729A codec samples of 8000 times per second. The system uses the same codec again on the other side to gather thousands of samples in a continuous audio signal. The human ear can not detect the tiny missing pieces between these audio samples. However, a fax may "hear" these missing pieces, and may not be able to properly reassemble the document or image being transmitted without them, which may cause a fax transmission to 'failure.
For residential users, here are the recommendations of some of our best VoIP providers for faxing house:
Vonage you can use your voice Vonage line for occasional fax, but if you plan to frequently fax, Vonage strongly recommend adding a dedicated fax line to your plan. A fax line is included with most business plans, and residential customers can add basic fax line to their package for $ 9.99 per month.
VOIPo: VOIPo does not guarantee that your machine will work with their connection and does not provide significant support if you have problems faxing. You can add virtual fax to your plan, which will allow you to send faxes from your computer and receive them by e-mail for $ 4.95 per month or $ 36.00 per year.
Phone Power: Phone Power recommends that you just connect your machine directly to the analog telephone adapter or ATA (see NextAdvisor Guide to VoIP equipment for more information on ATAs ), they send when you register. Phone Power also offers a function "Fax Catcher" which will send incoming faxes to your email if your machine is not connected to the line.
Phone.com: Phone.com offers some support using a traditional fax machine on the regular VoIP line, but warns that fax machines may not be reliable with VoIP. For best results, Phone.com recommend adding a second level to your phone number and use their Internet Faxing interface to send and receive faxes through your computer.
If none of these options sound for you, you might consider using a fax service by independent Internet as one of our top choices, MetroFax, MyFax or Fax87.