2006-07-05 - Choosing Skype Or A VoIP Service Provider
Article taken from www.voipnews.com.au
With the amount of media coverage Skype gets, its a little difficult to understand the difference between it and the growing band of specialist VoIP service providers or the increasing number of ISPs offering IP telephony services. VoIP News readers often contact us to ask what which type of service they should use. While the answer is different for every individual, we though a closer look at the options might make the comparison easier for them.
One of the huge advantages Skype has in the marketplace is the sheer number of users it has been able to amass to date. If it's totally free calls you are after, then signing on with Skype is a sure way to instantly give yourself access to millions of people to call. The inclusion of telephony functions in a growing list of Instant Messenger-type applications like Microsoft Live, GoogleTalk and Yahoo! Messenger puts them in pretty much the same position as Skype.
In most cases calls within a service provider's network are free, so if you sign on to a IP phone service with your ISP or a dedicated VoIP service provider, you will only be able to make free calls to other people using the same service.
This is the same with Skype, of course, but there are already a hundred million people or so using that service so your chances that the person you want to call has a Skype account is relatively higher than with your other options. Skype also has a global directory of users, so you might even be able to find who you are looking for by searching online.
Cheap Not Free
Of course, the cost of IP Telephony is very low, so you may be willing to accept cheap instead of free. Keep in mind that even Skype to Skype calls are not literally free. You still have to pay for your broadband connection and although voice calls don't take up much bandwidth they are very sensitive delays caused by other traffic as we will see later.
If the person you want to contact isn't on the same network, its unlikely you will be able to call them computer to computer, so you are going to have to call a regular phone number on the PSTN (Public Switched Telephone Network) also called the POTS (Plain Old Telephone Service). This is going to cost you money because your VoIP provider has to pay the telco that owns that system (in Australia that's Telstra) for the service. This is done at wholesale prices which should make it cheaper depending on how your provider structures their rates.
The main difference between Skype and other VoIP providers here is likely going to be that your ISP will charge you after the fact (post paid) while Skype will require you to buy a block of credit up front (pre-paid). This will mean using your credit card online.
Many dedicated ITSP (Internet Telephony Service Providers) will charge you a monthly subscription. Some, but not all include a bundle of ‘free' local, National or International calls in that price, much like a mobile phone contract.
Some are now offering free un-timed local calls - your ISP may structure their charges in this way and if you make a lot of local calls, this could be a significant incentive. But be wary if they are charging a high rate for timed local calls, a long chat with your mum down the street could end up costing more on a timed VoIP call than using the normal phone.
The call rates are likely to be pretty close to each other as they are in a competitive environment, but don't take this for granted. There's plenty of room here for price gouging, so it's going to be a matter of understanding your calling patterns and comparing the offerings.
Unless you want a normal phone number attached to your account, Skype subscription is free. So if your ISP expects you to pay a regular monthly rate, or an establishment fee to set up your account, you need to factor that into a comparison between the two.
SkypeOut calls (from your Skype phone to a regular land line) are charged at the same rate pretty much regardless of where it is. So if you are calling your mum down the street, it's going to cost the same as it would to call your old school buddies in another country. Skype offers what it calls The SkypeOut Global Rate which is good for about 20 of the most popular countries.
All SkypOut calls originating and terminating in the United States are currently free until the end of this year, so the situation there is a little different.
Phone Numbers
But call rates can change and if you are planning to sign up for a new phone number so other people can call in on your VoIP service, you are making something of a commitment to a new phone number.
Now keep in mind that neither Skype, nor any other of these new services, can really be taken as a complete replacement for your regular land line, but we'll get to that later.
If you are going to sign up for SkypeIn (a regular phone number that links to your Skype phone) you can get up to some nifty stuff. You could have a regular US phone number for callers there, plus you can have one in Sydney for your business associates there and you can have one in Canberra, Melbourne, Brisbane and so on.
SkypeIn number is not free, but if you are offering it as a service to customers or business partners it could make a lot of difference. It all depends on what you want to achieve with your IP Telephony setup.
Not all VoIP service providers can or will offer several numbers linked to the same account. In fact some will only issue you with a number that is local to where your account is held, so if you live in Townsville, you can't get a Sydney number. So if that sort of service is important to you check before you sign up.
One point to keep in mind about getting a new phone number is that there is no facility for Number Portability on VoIP numbers. If you change providers, the chances are that you will also loose your existing phone number. That could be a problem if you have business cards, letterhead, Yellow Pages advertising and so on.
Although the industry is looking at this issue, there's no indication when it might be possible and no guarantee that it ever will be made available. So keep that in mind.
Handset Issues
Next you might like to consider how you plan to make calls. Here you have basically three choices; a software phone client running on your PC, a USB handset attached to your PC, or a regular phone attached to an ATA (Analogue Telephone Converter) attached to an ADSL modem/router.
To the best of our knowledge, this last option is not possible with Skype, which means for the most part, your PC must be booted and connected to the Internet to make the call.
However, there are so many Skype-enabled accessories being released there could well be plenty of options. For example, by using one of the Wi-Fi enabled Skype phones, you would achieve a similar result allowing you to make calls over a wireless 802.11 network without starting up your PC.
Using Skype certainly doesn't tie you to your computer anymore. There is software available to let you use your Skype account from all manner of mobile devices such as Wi-Fi-enabled PDAs.
Another option is to use a USB DECT (Digital Enhanced Cordless Telecommunications) phone, which is much like a lot of the cordless phones available for the PSTN network. We use a Linksys CIT200 Skype phone which lets us wander about the office while using Skype. In this set-up a USB receiver is plugged into the PC and the wireless handset communicates through that to the Skype client running on the computer.
That's one of the huge advantages with Skype - there is a huge range of accessories you can get that are designed to work with it.
Of course, the softphone option is the cheapest here as it requires the least up-front investment in hardware. Many PCs come with microphone and speakers, or you can pay anything from $15 to hundreds for headset.
However, one of the disadvantages of these options is the lack of a failover alternative. If your Internet connection is down, the phone won't work no matter what type of phone it is.
Here's where the ADSL Modem/router/ATA comes into its own. We also have a device provided by Netcomm which acts as an ADSL2+ modem with Wi-Fi and router built in. It also has a telephone adapter. Using this set-up you can plug your regular phone into the modem and the modem into your phone socket.
In this way, if your VoIP service or broadband connection is out of action, the device will automatically place the call via the PSTN. This is particularly handy when it comes to emergency calls as we shall see next.
Emergency Dialling
A modem/router with a built in telephone adapter provides a backup for when your VoIP service or Internet access is disrupted. It should also do the same if you are calling an emergency number.
Emergency Dialling is one of the big issues with IP Telephony at present. In the US the Federal Communications Commission has recently forced all VoIP providers to re-engineer their systems to allow location information to be relayed to emergency number call centres. This has not yet happened in Australia, though it likely will at some point.
The issue is that your IP address (the number used to identify you on the Internet) is probably not fixed, most ISPs share a pool of numbers amongst their subscribers. Even if you did have a permanent IP Address there's no real way for the emergency services to identify a geographic location based on that information.
With a regular POTS number they look up a database provided by the Telco's and it lists your address along with your phone number because it is a fixed line. (Of course if you call on a mobile phone they can't tell where you are either, but nobody seems to worry about that.)
Location services are not so easy to do with a computer and it's the reason you will see many ITSPs say that there service is not a replacement for a regular phone account. So if something happens and you aren't able to tell the emergency operator your street address, they will have no way of knowing where to send the ambulance/fire engine/police. These failover devices solve that problem by routing all calls to emergency numbers via the PSTN automatically.
Network Issues (QoS)
One of the biggest differences to call quality when you are using VoIP services is dictated by the network your call travels across between parties. The PSTN works so well because it sets up a dedicated circuit between the two phones. Your call goes out on the copper wires from your house and travels along its own set of copper wires until it reaches the wires that lead to your recipient's phone.
Now this isn't strictly true anymore, but that's how it used to be. While most telco's aggregate calls onto long distance fibre and such, this dedicated circuit architecture remains in place in most telecommunications networks around the world. Many of the largest telcos currently have huge multi-billion dollar projects in train which are changing from this circuit switched approach to packet switched networks.
In a packet switched network, like the Internet, your call data is chopped up into little pieces and carried in packets of bite sized pieces to its destination. Each packet has an address of where it wants to go and at each step along the way a network router checks this address, works out the most efficient way to get the packet to that address and passes it along to the next hop - one step closer to the destination. This continues to your PC that has the address on the packet.
IP Telephony works exactly the same way. You are carrying Voice over this Internet Protocol network (VoIP).
This is where you can run into trouble. Your call data is being carried along the same network paths as everybody else's email, web surfing, music downloading Internet traffic. Some of the data that is carrying your voice could get stuck in a traffic jam along the way. You see, unlike a circuit switched call, different pieces of your VoIP call may take a different path heading off in one direction while the next piece takes another.
This means that at the end point, these packets might be delayed or arrive out of order. They might even arrive with errors and would have to be retransmitted. Of course this is okay if the data is an email or web page, but with real time applications like voice or video streaming this would be a disaster.
Now while your Skype or Instant messaging client might use smart software to make a good attempt to allow for this, in heavy traffic situations you will experience some jittery conversation or drop outs because essential pieces of the data is missing. Your caller can't be expected to wait until all the packets have arrived, put in order, retransmitted and so on until they hear what you said or every conversation would be like talking over a satellite link 15 years ago.
What a dedicated VoIP Service provider can do for you is reduce the amount of latency (traffic jams) your call data gets caught in. They do this by providing Quality of Service (QoS) rules along the way.
Each hop in the path your data takes is a device called a router (because it routes traffic). These routers make routing decisions based on a set of rules configured into the system. IF the router is told recognise voice traffic and give it precedence over email and everything else that passes through it, then there's less chance your voice call will experience dropouts and jitters at the other end.
Skype and other Instant messaging type voice software can't do this because Skype doesn't control the network your call travels over. It's carried over the 'public Internet' where everybody is competing for bandwidth.
With most VoIP service providers they either own their own network or buy time on dedicated links that are set up with this Quality of Service implemented. In a high-end business system they would also provide the link from your offices to their network centre so that they can control the data from end to end.
For most consumer and small business VoIP systems you use the public Internet provided by your ISP to get to your provider's VoIP switch, they carry it over their network (or a leased network) until it is switched back onto the PSTN.
Now if your ISP is serious about VoIP they will also make sure they are respecting this QoS right from your PC or IP phone, through to the call's destination.
Other features
Finally, the last thing you might want to consider is the feature set offered by your ISP or ISPT.
Skype (and a number of similar services such as Microsoft Live, Yahoo! Messenger or, GoogleTalk) allow you to make video calls and use instant messaging using the system. It's unlikely at this time that you can do this with the service provider you are comparing with. Skype also offers features such as conferencing that you might not find elsewhere.
Others such as call forwarding, the ability to use your account when you are somewhere else, voicemail, caller-ID, the ability to block callers and so on.
Although the cost is seen by consumers as the biggest in migrating to IP Telephony, for most business it's not about cost it's about the additional features they gain from the new technology. Some of these might not be relevant to you... yet.
This certainly isn't a definitive comparison of the Skype (style services) versus the ISP and ITSP services. It's really just a first draft, but it's a start.
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