The
Differences between ADSL service providers (“the options and pitfalls in your
choice of provider”)
When choosing your ADSL supplier, I recommend that you
consider the following factors which differentiate provider offerings:
Factor for
consideration |
Remarks |
Downstream bitrate |
4
Various bitrates are available
from 1 Mbit/s to 25 Mbit/s (ADSL2+). 4
Make sure that you can get the
bitrate you require for your current needs, but that there is also scope to upgrade
to a higher bitrate later. 4
Check the terms for an upgrade. |
Upstream bitrate |
4
Make sure that the upstream
bitrate is sufficient to meet your needs 4
There may be an option to
upgrade the upstream bitrate |
FastPath |
4
Usually an option – maybe at extra
charge 4
May be required be gamers and
others requiring rapid PING time response (i.e. low latency) |
ADSL2+ standard supported? |
4
The ADSL2+ or ADSL2 standard is
required for speeds above 8 Mbit/s – up to 25 Mbit/s 4
It is advisable to purchase one
of the most modern DSL modems – one supporting the ADSL2+ standard as well as
straight-forward ADSL 4
If your provider supports ADSL2+
then the door is open for an easy upgrade at a later date speeds up to 24
Mbit/s as may be required for video-on-demand, IP-TV and HDTV (high
definition television) |
Geographical service coverage |
4
Very few ADSL service providers
are able to provide nationwide coverage 4
Check that you are within the
coverage area of your preferred supplier (this ‘pre-qualification’ is typically
carried out by the supplier as part of his order process) |
Monthly charges for connection |
4
Check that you understand the
supplier’s tariffs and commercial conditions. 4
Sometimes the monthly
subscription includes a flatrate charge for unlimited data volume, sometimes
data volume charges are extra. |
Data volume charges – flatrate? |
4
Data volume charges might be per
MB (Megabyte) 4
There may be a fixed charge for
all volume up to a given GB (Gigabyte) volume per month 4
There may be a ‘flatrate’ charge
for unlimited data volume 4
Some providers also make charges
related to the time duration during which the line was connected – though
increasingly these charges are disappearing in favour of ‘always on’
connections and flatrate tariffs. |
Quality of Service (QOS) |
4
The quality of service (QOS)
provided by different ADSL providers can vary greatly. 4
It is difficult to assess the
quality you will receive in advance or from their website. 4
Of course, all providers promise
high quality 4
But they differ greatly in the
network capacity they provide in their backhaul/backbone networks – the part
of their network linking your local ADSL connection to the public Internet
itself 4
It is common for Internet
Service Providers (ISPs) and ADSL providers to provide their backhaul
capacity according to an average peak hour kbit/s data rate per customer
connection (e.g. 20 kbit/s per customer). This is equivalent to an
‘overbooking’ factor on 1 Mbit/s lines of 50 – there is only 1 Mbit/s of
‘backhaul’ capacity to the Internet for every 50 customer 1 Mbit/s ADSL
connections. 4
The higher the ‘overbooking
factor’ applied by the ADSL service provider, the slower your Internet
connection will respond at times of peak traffic loading. 4
To get some idea of a provider’s
QOS level before you order his service, you may like to consult the published
statistics of your national telecommunications regulator. 4
Most national regulators force
ADSL service providers (as well as all other telecommunications service
providers) to publish statistics on QOS – including waiting time to
installation, service QOS and responsiveness to fault handling |
Forced release every 24 hours? |
4
Many ADSL service providers
conduct a ‘forced release’ of each ADSL connection every 24 hours 4
If an application is running at
the time of the forced release it may be temporarily disturbed as the
connection is re-established 4
To mitigate the problem you may
choose to manually set up the first ‘always on’ connection sometime in the
very early morning – or at another period of very low usage |
DSL modem choice and price |
4
The range of DSL modems and the
prices offered may vary greatly from one provider to another 4
Equipment developed by companies
in the country of operation may be better optimised for local network
conditions than the offerings of international equipment and router providers
such as Cisco |
Fixed IP address |
4
Most ADSL providers allocate IP
addresses on a ‘dynamic’ basis. This means that your IP address is assigned
to you each time you re-establish the connection. For the duration of your
connection your IP address is unique and only available for your use,
although from time to time, your IP address assignment may change 4
A fixed IP (Internet protocol)
address may be beneficial when distributed servers or roaming users at other
locations have to access your site 4
A fixed IP address may also be
beneficial as a reliable means of identifying your site to other locations,
servers or applications for security purposes (though the fixed IP address is
not a ‘guarantee of identity’) |
Port restrictions |
4
In order to restrict certain types
of usage of your ADSL connection (this can have performance and security
benefits in some cases), your ADSL service provider may restrict the use of
certain port numbers. 4
If you require to use any exotic
data protocols or applications, check that the relevant port numbers are
permitted. |
Peer-to-peer usage restrictions |
4
Although many ADSL service
providers claim ‘flatrate’ tariffs, some are not keen on customers who use
their connections at their maximum bitrates for prolonged periods of time
(e.g. for permanent peer-to-peer data exchanges or data distribution). 4
Some operators reserve the right
(in their terms and conditions) to cancel your service and remove your ADSL
connection or migrate you to a different tariff or service. 4
If you intend heavy ‘peer-to-peer’
usage it may be prudent to check this with the service provider upfront. |
Hosting package/email included? |
4
Many ADSL service porviders
include a web hosting package including your own Internet domain name (e.g. www.yourname.com)
as part of your ADSL subscription. 4
This often includes software
tools, email accounts and an anti-virus software subscription. 4
But do not pay extra for this if
you don’t need it. 4
Always compare the direct cost
of an anti-virus subscription with the annual charges quoted on the websites
of the major providers (e.g. Norton Antivirus). |
Installation and other one-time charges |
4
Installation and one-off charges
(including postage costs for sending you the splitter and/or DSL modem) can
be significant. |
Contract lock-in period |
4
Many ADSL service providers
offer terms including no installation charge – but at the cost of a 12 month
or 24 month minimum contract commitment. |
Upgrades |
4
Do the commercial terms allow an
upgrade or downgrade of your bitrate at no charge? |
Installation assistance and service |
4
Does your provider have a 24
hour telephone hotline to assist you when you can’t get things to work? 4
Is the hotline free or what are
the charges for this assistance? |