ADSL/SDSL/DataStream……the
wait is over!!!
ADSL provides
permanent Internet connectivity with speeds up to 40 times faster than a
standard modem. Installed on a standard
phone line, it provides you with simultaneous telephony and unmetered, fixed
charge Internet connectivity – you can talk/fax and transfer files
simultaneously.
Just compare
download times for a 2 Mb file from the
Internet è
|
28.8 Modem
|
33.6 Modem
|
56.6 Modem
|
ISDN 128K
|
ADSL 512K
|
ADSL 1Mb
|
|
9 mins 42
secs
|
8 mins 18
secs
|
4 mins 56
secs
|
2 min 10
secs
|
32 seconds
|
6 seconds
|
What is ADSL?
Asymmetric Digital Subscriber Line (ADSL) is a permanent,
high-speed digital connection run on a standard analogue phone line. The
installation of an ADSL modem and splitter in both the telephone exchange and
on your premises converts the twisted copper pairs into a permanent high-speed
digital connection to the net. It allows voice calls to be made on a standard
telephone at the same time as accessing the Internet.
ADSL provides you with:
l
Always on 24x7 connectivity
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A fixed IP address(es) denoting your own distinct presence
on the net
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Instant access to email and web
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Fixed rate unmetered internet access
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Simultaneous Internet and phone usage
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24- hour technical support service
ADSL is a contended service, which means you will share
the available bandwidth with a number of other users. This will effect the
amount of bandwidth available to you dependent on the number of other users
online at any given time. Contention ratios for business broadband include 20:1, meaning
up to 19 other users will share your bandwidth, 5:1 and 1:1.
What are the benefits?
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Permanent access to the Internet allows your business to be
in constant communication with your customers and business partners
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Fast, reliable service gives your business the power to
sharpen its competitive edge
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High bandwidth capability enables you to rapidly transfer
large documents and download software, maximising your investment in IT
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Network capability provides fast multiple user access
boosting employee productivity
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Simultaneous access to the internet and telephone or fax
line increases your business efficiency
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Unmetered Internet access allows more effective budgetary
control
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Uncontended ADSL – guaranteed unshared
bandwidth at all times
l
DataStream – Provides dedicated ADSL
connectivity for your home workers, small branches and other stakeholders,
supports ATM-based high-speed digital transmissions. Can be configured to
provide corporate and public sector organisations with a secure and resilient
VPN (virtual private network) solution, converged solution, VoIP and even video
over IP. Can be offered as a fully managed service.
l
SDSL – Another viable
alternative to the traditional leased lines that offers a high upload as well
as download bandwidth plus all the associated benefits of broadband.
What equipment do I need?
An ADSL service requires a standard analogue phone line
provided by BT, two dedicated wall mains sockets within 2 metres of the master
phone socket and a PC with the recommended minimum specification:
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A 10 base T Ethernet card or USB for single users
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TCP/IP communications stack
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Internet Explorer 4 or above with JavaScript enabled
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200MHz Pentium II or equivalent
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32MB RAM
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50MB available HDD space
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SVGA monitor
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Windows 95 or above
IMPORTANT: Please note that
the following are not compatible with ADSL:
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ISDN – (will need to convert back to standard line)
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BT Highway
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PBX lines
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Pulse Metering Facilities
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Coin box
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Any line provided by a provider other than BT
ADSL may affect other services on the telephone line such as security
systems and we strongly advise you to have these services tested once ADSL has
been installed.
So how does ADSL compare
with ISDN or leased lines?
ISDN involves paying a fixed line rental in addition to
incurring call charges for usage. Both ADSL and leased lines offer always on
connections and you pay a fixed flat fee. A leased line is typically more
expensive than ADSL but guarantees bandwidth in both directions and is
therefore suitable for applications that involve heavy use in both download and
upload of data. ADSL is asymmetrical and offers far greater speeds downloading
up to 2000Kbps compared to 256Kbps uploading. ISDN is limited to a maximum
speed of 128Kbps.
|
Features
|
Dial Up
|
ISDN
|
Leased Line
|
ADSL
|
|
Additional Call
Charges
|
P
|
P
|
O
|
O
|
|
Simultaneous
Voice Calls on same line
|
O
|
O
|
P
|
P
|
|
Always On
Connection
|
O
|
O
|
P
|
P
|
|
Multi User
Connectivity Option on same Line
|
O
|
P
|
P
|
P
|
|
Receive Real Time
email
|
O
|
O
|
P
|
P
|
|
Minimum Contract
Term
|
O
|
P
|
P
|
P
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Huge cost savings in addition to speed:
|
|
Monthly
Rental*
|
Time
connected to the Internet based on a 20 day month
|
Monthly
Internet Call Charges*
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Annual
Total
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Annual savings with ADSL
|
|
ISDN 2e
|
£46
|
1 user (2
hrs per day) Low usage
|
£60.40
|
£1276.80
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Low Usage
|
|
ADSL500
|
£34.00
|
Always-On
( up to 15 users )
|
None
|
£408.00
|
£868.80
|
|
ISDN 2e
|
£184
|
4 users
(2 hrs per day) Medium usage
|
£241.60
|
£5107.20
|
Medium
Usage
|
|
ADSL2000
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£59.00
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Always-On ( up to 50 users )
|
None
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£708.00
|
£4399.20
|
*Based on
BT’s most popular ISDN 2e offering. Call charges assume 2 hrs Internet usage
per ‘user’ per working day.
How many computers can I
connect to a single ADSL connection?
ADSL is delivered with a
modem/router which when linked to your existing network, will provide
simultaneous Internet connectivity to all the workstations on your network.
Is it possible to host a
web server using ADSL?
Technically Yes, But this is
not recommended. A web server’s task is to upload data as quickly as possible
and as ADSL has a maximum upload speed of 256Kbs (which is also contended),
ADSL does not provide the best option. A leased line or web hosting package
would be more suitable. For details contact us on 0870 900 9092
Where is it available?
ADSL is now available to the majority of UK homes and
businesses with coverage at around 99% of homes and businesses.
To check the availability of ADSL in your area, simply email your
postcode and telephone number to us at check4adsl@smarttalkuk.com
Please note that we cannot guarantee installation of ADSL on
your telephone line, even if on an ADSL equipped BT exchange. ADSL requires a high quality line within 3km
of the exchange and BT will refuse to accept orders on lines that do not meet
their criteria for installation.
The
ADSL package comes with the choice of three capacity levels – 500 Kbps, 1Mbps
or 2 Mbps. It also comes with the option of NAT or No NAT, and whether you
choose it or not will depend on your requirements and priorities. Here are the
pros and cons:
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Pros
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Cons
|
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NAT
With
the NAT option, all the computers on your premises have their own individual
and private IP address. NAT then converts these into one global IP address.
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h NAT is
more secure, as internal PCs in your private network cannot be seen by the
public via the Internet
h Efficient
use of global IP address as only one is required
h You can
easily add PCs to your local network without the need for additional global
IP addresses.
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h You cannot
host your own e-mail or web servers because the individual PCs are not
identifiable from the web
h As there is
only one global IP address, you cannot receive e-mail on individual machines.
However, if you choose this option, we are able to host your e-mail system
and web space on the carriers network.
|
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No NAT
If
you decide against the NAT option, each PC is assigned its own public IP
address.
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h Each PC has
a direct connection to the Internet and can be seen from the Internet
h You can
receive e-mail on individual PCs
h You have
the ability to host your own e-mail or web servers because each PC has its
own global IP address.
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h All PCs are
vulnerable to security risks as their global IP addresses are all
public facing. You will need a firewall to protect
your PCs
h Inefficient
use of global IP addresses.
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