VoIP FAQ

VoIP has the same meaning as Voice over IP, or Voice over Internet Protocol.

Voice over Internet Protocol diffuses voice traffic over the internet. IP, or Internet Protocol has been designed to work for networking data and upon its’ accomplishments, the Internet Protocol now uses voice networking.

Voice over Internet Protocol is able to set up different tasks as well as delivering services that are slow or that has a high cost associated with it when using PSTN:

  • When using one broadband telephone line, there can be more than one phone call at a single time. Voice over Internet Protocol is able to direct additional phone lines to businesses.
  • Telephone and cable companies charge extra for other features, such as caller identification, caller forwarding, and auto redialing, which are easy to handle with Voice over Internet Protocol technology.
  • Unified communications are able to be secured through voice over Internet Protocol technology as well, since it permits integration for other available services that are on the internet. Some examples are instant messaging and video conversations.

There are many advantages to using Voice over Internet Protocol which more businesses are setting up every day.

When describing unified communications, it is a process that all types of communication, communicating devices, as well as media are integrated together so users can contact each other anywhere in the world in real time.

Through using unified communications increases business procedures as well as simplifying human communications.

Direct Inward Dialing is also known as DDI in European countries is a feature through phone companies for customers to use their PABX system, which puts away a certain range of numbers that are used on one or several telephone lines.

Direct Inward Dialing’s purpose allows companies to assign individual phone number to each of their employees without having separate telephone lines for each of them. This way the traffic is split and can be managed effectively.

Direct Inward Dialing requires the user to have an ISDN, which is a digital line, and then the phone company dedicates a range of phone numbers for that business. There is also equipment that needs to be installed on site which is gateways, or T1, E1, or BRI cards.

Interactive Voice Response is a new technology that is able to communicate to a user through a configured voice menu in real time. With the Interactive Voice Response system, callers are able to go through options by pressing numbers on the phone.

These systems are able to handle high call volumes at any time. With an Interactive Voice Response system, businesses are able to reduce costs and improve customer satisfaction since callers are able to call in twenty-four hours a day. There is no need for hiring humans to be working around the clock anymore.

Users are able to use Interactive Voice Response in banking by phone, scheduling flights as well as voting.

ENUM is also known as Telephone Number Mapping. This acronym has a fabulous idea behind it: A user is able to be reachable anywhere in the world with using only one phone number—this method is the most cost efficient route. Telephone Number Mapping uses a telephone number and is able to link it to a certain address on the internet that is published in a DNS system. The owner of the phone number is able to route where a call should be directed to from a DNS entry. There can also be different paths for certain types of calls coming in. An example would be that a user is able to label a route for a caller looking for the fax machine. Telephone Number Mapping requires a phone to use it.

A business is able to register a Telephone Mapping Number like one registers a domain for a website. Many current voice over Internet Protocol providers provide this service for free.

Using the mapping services is still new and not widely known. This is also another step in providing a more personal mobility service in the future.

Another term for a Voice over Internet Protocol telephone is a SIP phone or a soft phone. This gives the caller the ability to call to any other soft phone, landline, or mobile phone by using voice over Internet Protocol. That way the voice is carried by the internet instead of using the PSTN systems.

A Voice over Internet Protocol phone is easy software to use or it can be a hardware device that may look like a phone.

Some of the Voice over Internet Protocol telephone features are Call Park, caller ID and call transfer.

FAX has been designed to work on analog networks, so they do not work very well on a Voice over Internet Protocol network. FAX communication uses a signal differently than a voice communication does. When Voice over Internet Protocol compresses and digitizes the analog communications, it was created for voice and not FAX. There are different items that can be thought of when a business switches over to a Voice over Internet Protocol system.

If a business wants to keep using their fax machine, and they have a Voice over Internet Protocol system in place, they need to have a Voice over Internet Protocol gateway and an ATA that supports a T38. The protocol for a T38 was designed to be able to allow faxes to move over a Voice over Internet Protocol network. An example of this is provided here.

There is also another way that one can convert to a fax that is computer based and also chooses a Voice over Internet Protocol system that allows faxes. A Phone system called 3CX for a Windows OS includes a server for faxes to travel over. The fax is then converted into a PDF and emailed to the receiver. This method allows faxes to be sent anywhere in their network when they use the Microsoft Fax client and server. This is free with the Windows Server years 2003 and 2008.

Another method of dealing with faxes is to connect the machine to the phone line; therefore bypassing the Voice over Internet Protocol system.

CODECS converts analog signals to digital signals when transmitting over a network. These are the CODECS that are used today:

  • iLBC-15Kbps, 20ms FS (frame size); 13.3 KBPS, 30 FS (frame size)
  • GSM- 13Kbps, 20ms FS (frame size)
  • ITU G.711-64 Kbps, sample base, Aka Alaw/Ulaw
  • ITU G.722 – 48/56/64 Kilo bytes per second
  • DoD CELP 4.8 Kbps
  • ITU G.726 – 16/24/32/40 Kilo bytes per second
  • ITU G.728 – 16 Kilo bytes per second
  • ITU G.729 – 8 Kbps, 10ms FS (frame size)
  • Speex – 2.15 to 44.2 Kilo bytes per second
  • ITU G.723.1 – 5.3/6.3 Kbps, 30ms FS (frame size)
  • LPC10 – 2.5 Kilo bytes per second
Businesses who implement a Voice over Internet Protocol system needs to use an Internet Protocol telephone.

Internet Protocol phones are also known as voice over Internet Protocol phones, SIP telephones or soft phones. These are exactly the same and all transmit voice over Internet Protocol.

Using voice mail is a system that businesses use to send, store and receive audio messages. This is like someone’s answering machine at home.

Every extension in the system has their own individual mailbox; so if a number is busy or the line isn’t answered, the telephone caller is forwarded to their mailbox to hear a recorded message by the operator. The message will let the caller know what to leave in their message and how to reach another extension in the system.

Using voice mail in business is crucial when keeping lines of communication to run efficiently and effectively.

When businesses want to switch over to a voice over Internet Protocol system, they are not able to keep dial-up internet, since this connection is not fast enough to support voice. Businesses are able to switch over to a broadband internet connection, such as cable or dsl, in order to achieve top quality. The bandwidth that is required for voice over Internet Protocol is 88kbps when sending or receiving. If one is not sure how fast their internet connection is, a voice over Internet Protocol speed tester is able to provide the answer. If a business wants to have several voice over Internet Protocol telephone lines at the same time, it will require more bandwidth. One way to calculate how much a business user may need would be to multiply 90kbps by the maximum number of phone lines that will be used at any given time. An example would be a small office who have three voice over Internet Protocol phone lines will need (3 x 88 kbps= 264kbps) in both uploading and downloading directions. A good rule to remember is to only use about fifty percent of the maximum bandwidth in order to achieve the best signal.
Voice over Internet Protocol is not able to support satellite Internet services. Most of the time the conversation is clear, but satellites have delays in their internet service that people in a conversation will have several pauses throughout their conversation. It will take a moment for the voice to reach the other side of the caller. The signal takes about a half of a second for the satellite to receive it and another half of a second to transmit it back to the ground. So it takes one second for the person to hear what the other person just said. This system is similar to using a walkie talkie.

Using cable or DSL connections for voice over Internet Protocol telephone usage is the best way to have a conversation. Voice over Internet Protocol along with satellite internet will work but will have pauses in between conversations.

The quality has improved steadily since its creation of the Voice over Internet Protocol system, and now it exceeds the quality of analog phones. Determining voice clarity depends on the system provider as well as the internet connection speed. See the checklist for details.
An ATA device is also known as an analog telephone adapter, which allows a standard phone to be connected through the voice over Internet Protocol connection. The adapter converts the analog signal into digital data so it can be transferred through the internet. These adapters are good for basic use but are not compatible with all Voice over Internet Protocol features. If a business wants to take advantage of all of the features, they need to purchase an Internet Protocol phone.
A new spinoff of the voice over Internet Protocol system is having a virtual or hosted pbx. This way, small and medium businesses can have an enhanced phone system without purchasing phone equipment. The whole system is operated and maintained by their service provider. A pbx lets people work from home, hotels, or cell phones while being connected to their business phone system. This is just like a fortune 500 system, people can use call transfer, hold with music, conference calls, or use an automated attendant to direct calls.
Quality of Service, or QoS is an excellent feature of routers that connect to the internet service provider. VOIP is a real time protocol which means if anything interrupts a digital signal, that the quality of the call will be diminished. This happens when people upload or download large files, or share files with peers. The QoS on the router ensures that the bandwidth of lower priority items, such as sharing files does not interrupt with the voice signal. Quality of Service ensures enough bandwidth to voice over Internet Protocol communications to ensure a higher clarity of the call. This is a good idea because many applications are shared through the internet when using voice over Internet Protocol. Another option is to have a separate connection to the internet so the voice over Internet Protocol signal is not interrupted, in that case the QoS is null.
In many cases a user is able to keep their phone number by transferring it to allow the user to receive all of their calls via Voice over Internet Protocol. This all depends on if they have service in the place where the phone number is.
A computer does not need to be on, just the internet connection to be working. All the user needs to do is plug the phone into the voice over Internet Protocol adapter or the Internet Protocol phone into the internet and there will always be an active telephone service.
Another benefit in having voice over Internet Protocol is to be able to have a phone number in a different area code where one does not live. Many businesses want to be present in different cities with a local number customers can call, and the company can be in a completely different part of the country. Residential users are able to get local numbers for their families to call without being charged long distance.
This is possible only if the user has access to broadband internet connections. The user is able to take their adapter with them when traveling so they can be reached. Many voice over Internet Protocol customers use a soft phone on their notebooks so they can receive phone calls wherever they are in the world.