[Zsd-news] ZSD October Newletter

[Ian Forbes]

Hi All


ADSL REVISITED

Back in May I touched on Telkom's ADSL service. At that time I had some quite 
good things to say about it. Since then a lot of water has flowed under the 
bridge, many businesses have signed up for ADSL lines. Some of these 
businesses have had better experiences than others with ADSL and I know of a 
few who have cancelled their ADSL lines again.

It is worth considering the strengths and the weaknesses of the ADSL service. 
On the one hand it has the potential to provide a 24 hour 7 day per week high 
speed internet connection. On the other hand it can cause endless frustration 
if you need to access overseas sites and with regards to security it can open 
up a can of worms - litterally!.

The STRENGTHS of the service are:

Speed - it has the potential to run 8 times the speed of an ISDN line.

24/7 capability - the connection can be kept live for virtually 24 hours per 
day 7 days per week.

Capped monthly cost - no telephone call unit charges and no surprise phone 
bills.

The WEAKNESSES are:

Very slow international bandwidth, particularly during work hours. If you need 
to connect to a "business to business" (B2B) website or "virtual private 
network" (VPN) located outside of South Africa, the service probably will not 
work for you. Even downloading e-mail from "POP" servers located overseas is 
not recommended.

Dynamic IP address. The service gets reset and a new IP address is allocated 
every 24 hours. This makes it impossible to run servers such as web, mail and 
dns servers on these ADSL lines. However ZSD do offer a "dynamic DNS" service 
when ADSL is used in conjunction with our Zslic e-mail/firewall server. This 
opens the door for some applications.

Not available at all locations. Check on the Telkom website to see if your 
exchange area is supported. Even if it is listed, beware the service cannot 
be installed in all local premises.

Limited monthly traffic allowance. If the traffic to one ADSL account within 
one calendar month exceeds 3 Gigabytes the bandwidth to that account is 
restricted to a barely useable level. Fortunately 3 GB per month is enough 
for most properly managed small to medium sized businesses. If you exceed 
this, it is possible to purchase additional login accounts which provide an 
additional 3 GB allocation for under R250 per month.

Security and control issues. ADSL puts your site on-line 24/7. If you do not 
have proper management with regards to firewalls and security upgrades, it is 
very easy for PC's to be infected with worms etc. Most sites which exceed the 
3GB allocation do so after they have become infected with malware. It is also 
necessary for management to control the use of ADSL resources on their sites 
to prevent abuse of the 3GB allocation, for security reasons and also to 
prevent abuse of office man hours.

Monopoly supplier. The basic ADSL line is a monopoly service that can only be 
purchased from Telkom. The ISP "bandwidth" account can be purchased through 
most ISP's, including ZSD - but currently the underlying service is only 
available from one bulk supplier - Telkom. This is unlikely to change as the 
service is structured in such a way that no other ISP can provide ADSL 
bandwidth at a competitive price. E-mail accounts and associated services are 
available from all ISPs.

Price. The cost of the service (budget from R920 per month) is out of the 
reach of most home users.

Conclusion.

In the early days, around the time of my May newsletter, the speed of 
international bandwidth on Telkom's ADSL service was respectable. In later 
months it slowed down and we received many complaints and the service earned 
a bad reputation.

More recently things seem to have improved somewhat. Currently downloads from 
international sites during working hours are usually faster than analogue 
links but sometimes slower than ISDN ones. Connections to local sites, like 
S. African banks and ZSD's e-mail servers, have always been reasonable.

On balance ADSL can be an extremely useful tool in many businesses. However it 
will not work in all circumstances. It is worth doing some homework before 
you commit to the ADSL service. If you have any queries, contact ZSD.

ZSD are working on systems to increase the usability and flexibility of the 
ADSL service. We currently offer a "dynamic DNS" service, which when coupled 
with our "Zslic" firewall/e-mail server facilitates remote access to 
computers on the users' Local Area Network. This allows users to access 
e-mail from remote locations and consultants to do remote support of 
computers on the site. We are investigating VPN systems for use on ADSL and 
also the use of ADSL as a "top up" service to provide extra bandwidth to 
sites with existing diginet lines.


AN INTERESTING ALTERNATIVE

An alternative to ADSL has recently become available. Sentech, the company 
which used to be part of the SABC and currently provides broadcast services 
to them and other radio and TV stations has recently been awarded a licence 
from ICASA to provide internet services via satellite. They offer a full 2 
way service which utilises similar dishes as those used for satellite TV. The 
advertised speed seems similar to ADSL but there is no bandwidth limit and 
users get a fixed IP. The cost is R3000 per month. However there is a 
requirement to sign a 3 year contract. By the end of that period there should 
be a competitor to Telkom and hopefully prices will fall. The main advantage 
of this service is that it can be used anywhere, even in areas where there 
are no Telkom services.

Regards


Ian Forbes