What is ADSL
What are the key
benefits of ADSL broadband for me?
What are the key
benefits of ADSL broadband based services for
How fast is it?
Who are our ADSL
broadband based services aimed at?
What can ADSL
broadband be used for?
What do I need in
order to be ADSL broadband serviceable?
Are there any
Service Constraints I should be aware of?
What services on
my line are incompatible with ADSL broadband?
How does ADSL
Is my fax
compatible with an ADSL broadband set-up?
broadband affect my normal telephone connection?
calls be charged separately?
keep an existing telephone number?
responsible for billing?
broadband affect my burglar or security alarm
equipment do I need?
Can you tell me
more about the line testing and validation?
What is the
minimum contract period?
If I move
premises what will happen to my ADSL broadband
Who do I report
Is it dangerous
to be permanently attached to the Internet?
Which IP services
are compatible with ADSL broadband?
Can you explain
how the contention ratios work?
What about other
ADSL broadband, or Asymmetric Digital
Subscriber Line technology is a means of
transmitting digital information at high
bandwidth down existing copper telephone cable.
It is permanently 'switched on', unlike normal
dial up access and is asymmetric in that it uses
most of the available bandwidth downstream. This
makes it particularly suitable for applications
where customers expect to receive more data than
they transmit such as for Web browsing, use of
corporate intranets, and reception of digital
audio-visual material. The technology also
supports analogue connection on the same line,
which enables voice or fax calls to be made
Firstly, the Speed. ADSL broadband
provides high-speed digital access - e.g.
potentially 10 to 40 times faster than today's
typical modems. It’s Always On. You will no
longer have to waste valuable time oTELKOMaining
a dial-up connection to your Internet Service
Provider or Corporate Intranet It’s Flexible. It
does not affect the normal telephone, so you can
make and receive telephone calls or faxes whilst
ADSL broadband based services will allow
SME's and Corporates to:
* Take full advantage of broadband capabilities.
* Offer innovative services to your end user
* Extend the reach of your Intranet to encompass
your remote teleworkers and satellite offices.
* Manage and predict your costs with the flat
rate charging scheme
Typical rates for ADSL broadband are shown in
the table below. Downstream speed Upstream speed
Up to 500 kbit/s Up to 250 kbit/s Up to 1 mbit/s
Up to 250 kbit/s Up to 2 mbit/s Up to 250 kbit/s
This is between 10 to 40 times faster than
today's typical modems.
Our services are aimed at a wide range of
consumers. Corporate business users will be able
to provide their teleworkers or satellite
offices with remote access to the corporate
network, whilst home users will be able to take
advantage of the incredible download speeds to
view digital media on the Web, such as movies,
music and similar bandwidth hungry applications.
ADSL broadband's higher potential bandwidth has
the potential to enhance access to existing
services and applications and stimulate the
development of new ones:
The access speeds available with ADSL broadband
available make it practical for web sites to
carry more multi-media rich information such as
embedded video clips, animations and good
quality audio - significantly enhancing the
Intranet access Fast access to the
Intranet makes teleworking an attractive option
- which in turn can bring benefits to both the
organisation and the individual
TV based services
ADSL broadband can be used to deliver
interactive applications to the TV, such as real
time video and audio, home shopping and home
ADSL broadband will be the catalyst for a wealth
of new information, education and entertainment
Broadband is dependent upon TELKOM's
roll-out schedule for ADSL broadband
serviceability of your geographical area.
TELKOM have chosen a number of criteria to
establish which exchanges should be provisioned
for ADSL broadband first. These included demand
for bandwidth and where the early adopters of
these services are most likely to be located.
There are a number of factors that will
determine whether you will be able to take
advantage of ADSL broadband.
That you are a TELKOM subscriber. You must have
a valid contract for the use of a TELKOM
analogue direct exchange line forming part of
the TELKOM network over which the ADSL broadband
service will be provided. Note that if you rent
your premises, you must have a valid contract
for a TELKOM or Calls & Access provided PSTN
line. It is not suitable that the contract be
held with your landlord rather than yourself.
Whether TELKOM has upgraded your telephone
exchange to ADSL broadband technology, and
whether you are located within a specified
distance from the exchange. That you are aware
of the installation procedure and requirements
in terms of equipment as well as location. That
there are no incompatible services on your PSTN
line. That you have sufficient mains power
sockets for the TELKOM NTE (Network Terminating
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The transmission performance of some
local loops will mean that it is technically
impractical to deliver ADSL broadband service to
all end users with a particular serviceable
area. Telkom reserves
the right to refuse ADSL broadband installation
even if you are situated in a serviceable area.
ADSL broadband service is not compatible with
these TELKOM services: Subscriber private
metering 30k loop Private circuits Red ABC
RedCare Meterpulse facility PBX lines It is only
possible to provide a single broadband service
over a single TELKOM or Calls & Access PSTN
ADSL broadband operates over a normal
telephone line. This means that there is no need
to dig up any roads to replace cable and install
it. The ADSL broadband signal is carried by two
ADSL broadband modems - one in the end user's
premises and one in the local exchange. These
ADSL broadband modems are designed to exploit
the physical transmission capabilities of the
copper line to the maximum extent. The resultant
‘broadband’ medium is used to achieve much
higher data rates than were previously possible.
Two 'splitters' (filters), one in your premises
and one in the TELKOM exchange, separate the
telephony signal from the ADSL broadband signal.
This means that telephone calls can be made at
the same time that data is being sent or
received (i.e. a customer can surf the Internet
and still make telephone calls concurrently).
It is not guaranteed that your existing fax
machine will work after you have installed ADSL
broadband. Please check with the fax machine
manufacturer/vendor to check ADSL broadband
You may notice a slight change to how your
telephone sounds after you have ADSL broadband
installed. This is normal for ADSL broadband
lines and is not a fault. Any standard modems
operating on your PSTN line (standard telephone,
not the ADSL broadband line) may operate at a
reduced speed after ADSL broadband installation
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Yes. Normal telephone rental and call
charges will still apply.
Installation of ADSL broadband may
adversely affect security or burglar alarm
systems that use your PSTN telephone line and
fail to operate correctly. You should check with
your suppliers for compatibility of your system
before arranging for ADSL broadband
The service supports most protocols
including Telnet, SMTP, HTTP, FTP, TFTP, VDO,
RealAudio, Cu-SeeMe, QUAKE (2.8.0). ADSL
broadband will also support instant messaging
and communication programs such as NetMeeting,
ICQ or Microsoft Messenger. Some of the advanced
functions of these programs, such as video
conferencing or file sharing, will not operate
behind a firewall or Network Address Translation
(NAT) without some technical configuration, or
possibly not at all. If you have any questions,
consult the user Help for the specific program.
The equipment required and minimum specification
of PC depends upon which installation you are
having, USB or Ethernet version. For the ADSL
broadband Home and ADSL broadband NetStart USB
installation, you will need the following:
PC with the minimum
specification of: Windows 98 or Windows
2000 operating system USB port (if you are not
sure about this, please see your supplier. The
ADSL broadband modem uses USB to connect to your
PC). 4-speed CD ROM drive 200Mhz Pentium or
above 32 Mb RAM or higher Video card/display
capable of 800x600, 256 colours SVGA monitor 16
bit sound card 150 MB free hard drive space For
the Ethernet multi-user modem/router
installation, you will need the following:
PC with the minimum
specification of: Network Interface Card
(10BaseT Ethernet port) TCP/IP communications
stack Netscape 4 or IE 4 or above must be loaded
onto at least one of the PCs connected to the
Other specifications will depend upon the
applications you want to use with your ADSL
broadband service and the operating system you
are using. For basic Internet browsing this
should be at least: Pentium 166Mhz, MMX or above
32Mb RAM or above 150MB available hard disk
space SVGA or higher rated monitor Video
card/display capable of 800x600, 256 colours
Windows 3.11, Win 95 or Win 98 - or, Windows NT
or Windows 2000 4-speed CD ROM player 16 bit
sound card Mouse or other pointing device If you
wish to use Apple MacIntosh on your network, the
machine should conform to the following
specification: Or a
Apple Macintosh with the following is
recommended: PowerPC 601 or equivalent
32MB System Memory 2-speed CD ROM player Video
driver and display capable of 800 x 600, 256
colours 100MB free space on hard drive OS8.1 or
higher Open Transport 1.3 Networking Software
10baseT Network Adapter with an RJ45 connector
You will also need appropriate lengths of
Ethernet cable to connect your PCs to the ADSL
broadband router/hub. Note that a length of 100
meters must not be exceeded between the PC and
After initial ordering, TELKOM engineers
will make preliminary tests on your line to make
sure that you are ADSL broadband serviceable. If
the tests conducted on your line show that
TELKOM are unable to install ADSL broadband at
your location, you will be told the reason for
this. Some examples of situations may be line
quality, distance from the exchange, incorrect
information being supplied upon application etc.
There is a 3 month minimum contract period. You
should however contact us rather than TELKOM if
you have any queries.
Your contract with TELKOM and ourselves
is for your specific location and subject to a
minimum period. This minimum subscription period
would remain payable if you move location
whether or not your new location is ADSL
broadband serviceable. If you require ADSL
broadband at the new premises then you should
make arrangements for a new installation and
your old contract will be replaced by a new one
You should report faults to us and not
TELKOM in the first instance. The only exception
to this is if the fault affects only telephony
Any computer that is connected using
ADSL broadband to the Internet is exposed to the
same security risks as a dial-up user, however
since ADSL broadband users are typically
connected to the network for longer periods of
time (always on) this risk is potentially that
much greater. You should be aware of the
potential of hacking attacks and the precautions
that you should take. Please read our security
examples of good security practice are:
Turn off your PCs when not in use. Turn off
Windows File and Printer Sharing Install a virus
checking software product and ensure that it is
maintained to the latest version. You should
provide a Firewall in the case of a sensitive
installation. You should provide encryption of
data transmission for sensitive data.
The USB modem and the Ethernet router solutions
have different contention ratios set up by
TELKOM, with these values set at 50:1 and 20:1
respectively. This means that for a Home user
with a USB modem, the TELKOM connection at the
exchange is shared with another 50 users. Whilst
some degree of performance loss will be
experienced during peak periods, it is generally
accepted that few people will be downloading or
uploading data all at the exact same time. For
the business user it makes sense to go for the
20:1 business version, which will not be subject
to so much slowdown at peak periods. The two
systems will be able to co-exist on the same
'local loop' due to TELKOM's network tunnelling
protocols, each connection being given its own
port on the exchange terminating equipment
Currently the Broadband services are only
available over a TELKOM PSTN line. A non-TELKOM
PSTN variant is being investigated.
What impact will UMTS have
on ADSL broadband? Universal Mobile Telecoms
Service - UMTS is the called the 3rd generation
mobile service. It is a mobile network whereas
ADSL broadband runs over a fixed network. So,
whilst UMTS will deliver broadband access too,
the two technologies are more likely to be
complementary rather than head-on competitors.
DSL Lite/G.Lite is a lower speed, splitterless
version of ADSL broadband. It is designed to
offer around 1Mbps of capacity downstream, and
120kbps upstream. Because there is no Splitter,
it is easier to install but does mean that the
end user may experience significant interference
between the telephony and ADSL broadband
services when they are used at the same time.
TELKOM's ADSL broadband based services are based
on the full ADSL broadband standard, rather than
DSL Lite. TELKOM is involved in the evolution of
the standard for DSL Lite but has no immediate
plans to launch services based on it .