VoIP Frequently Asked Questions

Q. What is VoIP?

A. VoIP is an abbreviation for Voice Over Internet Protocol. The analogue speech signal is converted to a digital signal and is packetised for transmission over the internet. The process is reversed at the other end of the link.

Q. Doesn't VoIP just mean Skype?

A. Absolutely not!! Skype is a particular version of Voice over IP. At the moment you need to run a program on a computer to use it. There have been some criticisms of Skype because it is a "closed" architecture, and if you have a more powerful machine it may take over some of the machine's resources to become a "node" and support the calls of other Skype users.

In contrast most VoIP providers use open standards like SIP, session initiation protocol, so that calls can be passed between different providers, and equipment manufactured by one supplier will work with another's.

Q. What do I need to get to be able to use VoIP?

A. You need a broadband connection and an ASDL modem. You don't need a computer - an IP phone can be plugged directly into an ethernet port on the modem or a router. If you do have a computer you can try using a headset with a softphone instead of an IP phone. If you would like to avoid getting an IP phone and would prefer to use an existing analogue phone and still be able to use your conventional phone line you should use an ATA. That's an "analogue terminal adapter" - we would recommend the Linksys PAP2T-UK. Finally you will need to register with a VoIP provider.

Q. What type of Internet connection do I need ?

A. Ideally, you should have a broadband connection ( > 128 kpbs). You need at least 64 kbps download plus 64 kbps upload bandwidth to make an uncompressed VoIP call. If you use compression codecs such as G.723 or G.729 the bandwidth can be compressed to approximately 20 kbps per call. Depending on how you use your Internet connection, you want to make sure that you have enough bandwidth left over for other internet usage like web browsing, e-mails and more importantly downloads.

Q. Which VoIP provider should I use?

A. It's hard to say, but see our Getting Started page to a find out a little more.

Q. How good will the sound quality be?

A. Providing you are using a reasonably good IP phone you shouldn't be able to tell the difference between a VoIP call and an ordinary phone call. One exception might be when you are using an on-board sound card on an older lap-top. If you do encounter this problem you should try a USB headset. The other occasion when you might experience a problem is that you might get a "rippling" effect on an ADSL line when you are downloading.

Q. Which IP phone should I get?

A. We like the Linksys 921 which is a relatively new design. If money is no object then go for the Snom 360, which is a good office phone. If you are just experimenting go for the Linksys 901, or just use the X-lite softphone on a computer if you have one.

Q. How difficult is it to get an IP phone working?

A. It's not too difficult. Some VoIP providers will auto-configure your phone remotely. Alternatively you can use the phone's keypad to see or configure its IP address and then use a browser to set other information - typically the address of the provider's SIP server and registration server and a user id and password.

Q. Does my computer need to be turned on to use VoIP?

A. Only if you are using a softphone.

Q. Who can I call with my VoIP phone?

A. If you've signed up for a full service with a provider then you can call anyone that you might call over the ordinary phone network, and you will dial exactly the same numbers. You will be charged by your provider, but the calls should be significantly cheaper than using the PSTN.

You will be able to call other people signed up with your provider for nothing by dialling the other party's caller id. Most good providers will also let you call people registered with another provider. Again the call will be free. Your provider might tell you to use a particular prefix for the call, or you might use a SIPBroker prefix like *211.

If you are trying to call fred at someorganisation, you might be able to call him using his internet address as, say, fred@someorganisation.co.uk, or if he is on extension 1234 as 1234@someorganisation.co.uk. Of course addresses like these can be difficult to type into some SIP phones. You may well find that even although your provider tells you that you can only make a call to other users who are registered with him, this method will work.

Q. Who can call me on my VoIP phone?

A. As far as the ability of other people with VoIP phones to call you, much the same scenario applies as the one above about whom you can call. In order to enable people to call you from the PSTN there are several ways in which this can be achieved. The first and most obvious way is by getting a PSTN number from your provider. Often you will get an 0871 number for free. If you want to have a local number you will probably have to subscribe. Note that with some providers the number doesn't have to be where you live. You can be in the UK and the number can be in New York!

Q. Can I get a phone to work with my Wireless Access Point?

A. There are a number of Wi-Fi phones that support SIP, like the UTStar phones and the Nokia E series which provide SIP and GSM. These can be set up to use your access point. They can also search for other access points, so you can take them with you when you travel and make calls from any available access points.

Q. When I travel, can I take my VoIP phone with me and use it?

A. If you can have access to an ethernet connection or wireless access point, then providing there are no firewall issues, you can use your VoIP phone as though you are at your desk.

Q. I travel overseas a lot, what will VoIP do for me?

A. As your VoIP phone will be registered with your provider in, say the UK, then you will be charged as though you were connected in the UK, which can make calls to PSTN numbers there very cheap. If you have another VoIP account at home, then you can call a phone there free. Some providers will let you register two phones with the same number so that both phones will ring simultaneously. Whether that's helpful or not when you are travelling it's hard to say!

Q. How reliable is VoIP equipment?

A. Generally speaking you get what you pay for. The cheapest IP phones may not have the best of quality components or may not be as durable as more expensive versions. The more recently designed equipment can be better. We only sell phones with proven reliability.

Q. What happens if I'm doing other things on my computer when I'm using an IP phone or a softphone?

A. The phone should work! Sounds from other programs may be heard however!

Q. Can I transfer my existing regular phone number to VoIP?

A. Some providers will let you do that.

Q. Can I dial 999 with my VoIP phone?

A. No, thanks to current regulations, emergency calls cannot be made using VoIP.

Q. Will my VoIP phone work when there is a power failure?

A. You will only get things to work if you have battery backup for your phone and networking equipment.

Q. Can I have a local code for my VoIP phone number, even if I do not live in that area?

A. If you want to have a local number you will probably have to subscribe. Note that with some providers the number doesn't have to be where you live. You could be in California and the number in Bradford!

Q. Do fax machines work on a VoIP connection?

A. Yes, although you will have to use an ATA (analogue terminal adapter) which connects the fax machine to an ethernet connection.

Q. I have a small business with an office, about 20 phones and I want to use VoIP, what do I do?

A. You should consider using an Asterisk based server. The server and configuration you use will depend upon your current set-up and how many changes you wish to make. Any existing ISDN lines you may have can still be used, although you might also want to take advantage of an internet connection to achieve cost savings as well as allowing remote staff or offices to connect as though they were in the office and at no call cost.

Q. How do I connect the phones in the bedroom, sitting-room and garage so that I can use VoIP?

A. You will have to decide whether you want to connect wirelessly or with ethernet cabling and that will dictate what equipment you should get. The Linksys SPA9000 will give you an exchange in a box, or else you might want to use a conventional PC or small server running the Asterisk program.