Choosing an Internet connection: Broadband flavors


If you are engaged in working online most times, then you must be aware that having a good internet connection is an essential requirement to help you enjoy your online working experience. This means making a few decisions. First, what type to go for: old-fashioned dial-up access using the modem that’s probably built in to your computer, or more expensive but faster broadband access via a special broadband modem. Second, which Internet Service Provider (ISP) to sign up with. Think carefully about this as some ISPs are better value than others, and because, if you get attached to the email address that an ISP supplies, you might find yourself feeling tied to that provider. The term broadband describes any high-bandwidth (“fast”) connection. The most common types are DSL and cable, though there are also other options, such as satellite and ISDN.

DSL (ADSL)

DSL has taken the Internet world by storm during the last few years, generally in its most common form – ADSL, which stands for Asymmetric Digital Subscriber Line. The “asymmetric” describes the fact that the speed at which you can download (receive) information is much higher than the speed you can upload (send). The “digital”, however, is a misnomer, since technically speaking DSL is an analogue connection just like regular dial-up – but much faster. One beauty of ADSL is that it works through standard phonelines but allows you to be online and use the phone at the same time. It achieves this by “splitting” the line (see box, left) into separate frequency bands for phone and Internet. The first question with ADSL is whether you can actually get it. The technology only works in homes within a few kilometres of a physical telephone exchange – and the exchange has to be upgraded to support the service. If you can get ADSL, the speed on offer depends on the technology within your exchange. Be aware that you won’t necessarily get the advertised speed – things get slower the further you get from the exchange, and even over short distances poor line quality and other interference can reduce speed. So don’t be surprised if, say, an 8Mb connection works out closer to 6Mb in reality.

Cable

If you can get cable TV, chances are you can get cable Internet too. Cable access offers speeds of up to around 10Mb, though, as with DSL, it’s usually offered some way below its full potential and priced according to the speed. While DSL is offered by scores of ISPs, however, cable is only offered by the cable providers, so it’s them that you need to contact to find out about availability and prices.

DSL or cable – which one to go for?

Until you’ve tried both in your own home there’s no way to tell which is better. Although the technologies have their own distinct advantages, in practice the speed and reliability differs between installations. Theoretically DSL should be superior because you get your own dedicated line; with cable, you have to share your bandwidth with your neighbours, so if everyone on your street is downloading MP3s at once, you can expect the connection to slow down. On the other hand, DSL degrades as you move further from the exchange. If you live more than 3.5km (2.2 miles) away, you may find yourself disadvantaged – if you can get it at all, that is. And the situation is further complicated by other factors such as the individual provider’s equipment and the number of existing subscribers. The best you can do is ask around your local area for advice.

Other broadband options

The catch with DSL and cable is that you need the right wire coming into your house. In many rural areas, neither is available, in which case you have various other choices.

Satellite

No matter where you live, you can probably get satellite Internet access. There are two types of satellite access systems: a one-way system means you receive information direct from a satellite, but you send information (including the “requests” for webpages and files generated when you click Web links) via a dial-up ISP. In a two-way system you send information back up to the satellite. Download speeds are often capped at 512Kbps or less, though 1–2Mb is now quite common. Upload speeds are limited to standard dial-up 33Kbps in a one-way system, but can be up to 256Kbps in a two-way system. While that’s fast, satellite suffers from fairly savage latency (time delay), so “real-time” data-heavy tasks such as online gaming and video phone calls can be problematic or impossible. Prices have traditionally been high, but they’ve dropped swiftly in the last few years and some providers are now offering prices comparable to DSL or cable. However, remember to add the price of dial-up access when looking at one-way systems, and the startup cost of buying or renting a dish and modem.

ISDN

ISDN splits a standard phone line into three channels (1x16Kbps and 2x64Kbps) that can be used and billed in various ways. It’s nowhere near as fast as DSL or cable – British Telecom have dubbed their home service “midband” – and it’s not as good value for money. That said, costs vary widely, depending on where you live and how the call charges are calculated, so you may get a reasonable deal. Thanks to almost-instantaneous connection, you’ll often only be charged while you’re actually transferring data, and you may be able to use the phone while online (with the Net automatically dropping to one channel when you pick up the phone).

High-speed wireless access

There’s little doubt that the future of broadband is wireless, the idea being that you could just turn on your laptop – at home or anywhere else – and find yourself connected to a super-fast wireless network. Some town and city centres are already flooded with Wi-Fi access, though in general the access fees are higher than for a private ADSL or cable account. That will change over time, however, and if you’re lucky enough to be within range of a community Wi-Fi connection (see box), you may not have to pay anything at all. Another wireless-broadband option is to equip your laptop with a 3G or GPRS broadband card, which will get you decent-enough broadband wherever you can get a mobile phone signal. Some recent laptops even have such cards built-in. Again, however, the access fees for these services – usually paid via your mobile phone bill – are relatively high for day-to-day use.

Fibre-optic broadband

Like high-speed wireless access, this is another “watch-this-space” technology that is likely to become far more significant in the years ahead. Where ADSL depends upon the existence of copper wire running from telephone exchanges into the home, for a fibre-optic broadband supply (capable of shifting 100Mb by zapping light down fine hair-like wires) you need fibre-optic cable running into the home. Though many countries have now upgraded their national communication “backbones” to fibre-optic, few have as yet tackled the mammoth task of replacing the copper on the other side of the local exchanges to allow a “ Fibre to the Home” ( FTTH) service.

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