The jargon that surrounds ISP’s can often be confusing, a problem easily exasperated by the new terms and complexity of modern broadband technologies. Asymmetric ‘Digital Subscriber Line’ (ADSL/ADSL2+) is one such method and a member of the globally popular ‘DSL’ family.
Presently the most prevalent broadband technology in the UK, ADSL is the best place to start when considering a higher speed service. We have subsequently pieced together this simple guide, which endeavours to explain the primary aspects of choosing an ADSL provider.
Should any of the terminology in this article confuse you then please see our JARGON BUSTER service to help better explain the finer points. Similarly our BROADBAND Section may also help to fill in some of the blanks.
What is ADSL?
Unlike other technologies (satellite, cable, wireless etc.), ADSL is unique in its ability to be transmitted over existing copper wire based phone lines (e.g. BT), which is why its coverage of current networks has been so swift. Cleverly it is also able to split a single line into two separate parts (voice and data), allowing users to both speak and surf separately at the same time, without the added costs of a 2nd line.
The ‘Asymmetric’ nature of the name identifies its inability to deliver the same speed in both directions. Instead, ADSL concentrates on high downstream (download) speed, sacrificing upstream (upload) performance to achieve greater coverage. Since most data is ‘downloaded’, the ‘upload’ limitations aren’t generally a point of concern for most consumers.
Sadly ADSL is not a portable technology and can only be married to one specific phone line, hence you will not be able to access your connection from other premises, only the one where it was originally installed. This is common amongst almost all broadband technologies.
Coverage – Can I get it?
Every provider offering ADSL services will also operate a coverage/availability checker. This simple piece of online software is able to check a buildings suitability for broadband via input of a phone number (line you want ADSL on) or postcode.
SamKnows offers a handy general broadband checker:
The results from this check will help to determine whether your line supports ADSL, although you should use your chosen ISP's own checker to determine the lines best speed. For example, you could order a 2Mbps (Megabites per second) package, yet find that your line only delivers 1Mbps. Most providers will make you aware of this beforehand.
In addition some ISP's are now offering 'up to' 8Mbps connections or higher, however it should be noted that few ever receive the maximum speed offered by these packages. Distance from exchange and interference can hamper quality, which has an aggressive impact on performance and forces the connect speed considerably lower than 8Mbps.
Most ISP's will therefore attempt to offer a "prediction" of speed, which you should probably reduce by a further 30% or so for more accuracy. For example, our 8Mbps line is predicted to deliver up to 5Mbps, but in reality we rarely get above 3.5 to 4Mbps. Bad weather, specifically electric storms (lightning), can also hamper performance.
[Next Page (2)]>>
Have something to say? Check out the ISP Review Forum -->