014.90.1 South Africa by F. Jacot Guillarmod" <ccfj@hippo.ru.ac.za>
There are several networks in South Africa. The most visible is Uninet-ZA, a research and academic network that links participating Universities and research organisations via low speed TCP/IP trunks. There is also a loose confederation of dialup uucp sites, known collectively as Sanet, which links together private individuals and commercial undertakings in order to exchange Usenet news and electronic mail. Gateways between Uninet-ZA and Sanet exist, but are 'unofficial' in that there is considerable uncertainty as to their legality in terms of third party traffic regulations.
Other networks include Fidonet, which has a substantial presence (and to which Uninet-ZA owes a considerable debt of gratitude for services rendered); there is WorkNet, which links up non-Governmental Organisations (NGO's) in South and Southern Africa; and finally, several of the larger commercial organisations (such as the SA Wool Board) have extensive but isolated TCP/IP based WAN's.
Recently, Uninet-ZA established a dialup uucp connection to provide email to the University of Zimbabwe in Harare, and is in the process of setting up a similar link to the University of Namibia in Windhoek. There is potential for converting these rather unsatisfying low tech solutions into dedicated TCP/IP links in the future.
Networking in South Africa took a giant leap forward in late November, when a dedicated TCP/IP link to the United States was commissioned at Rhodes University in Grahamstown. This link connects Uninet-ZA to RainNet in Portland, Oregon, and from there into Alternet, and finally into the NSFNET.
Before this dedicated link was installed, connection to the Internet was indirect, via uucp dialup between two Unix systems acting as gateways between Uninet-Za and the Internet. Traffic volumes on this link had been showing continuous growth, and the cutover point, where it became cheaper to rent a dedicated circuit than to continue with dialup, were reached many months ago.
The process of cutting over from dialup uucp to a dedicated TCP/IP link has not been trouble free. The link itself is a 9600 baud analogue circuit, but use of V32.bis modems increases throughput to an effective 14.4kb. The routers on either end are normal PC XT's, running the public domain ka9q package. On a physical level, the link is remarkably stable. The cutover was planned in several stages so as to integrate the Domain Name universes as painlessly as possible. The first phase was to change the transport from uucp to SMTP between the original gateway machines, while leaving Uninet-ZA and it's dummy root domain isolated. The switch over went smoothly.
What was totally unexpected was the traffic volume. Within six hours of the link being in place, there was a mail storm, consisting of replies from mail based archive servers. The feeding frenzy had begun. Within the blink of an eye, there were tens of megabytes of electronic mail queued up, and more pouring in while users all over South Africa determinedly tried to import the entire Simtel-20 archives as soon as possible. The fix was to increase the number of machines acting as gateways on either side of the link, and to artificially filter the 'worst' of the traffic until the situation stabilized. In all of this, surprisingly, the bottleneck was on the gateway machines themselves, and not on the bandwidth of the link.
The next phase of the integration was to ensure that RIP was propagating effectively between Uninet-ZA and RainNet - a painless process. Slightly more painful, in terms of paperwork, was providing detailed lists of IP network numbers so that the router blocks into Alternet and NSFNET could be lifted.
The final phase of this exercise, which is in progress, is to merge the Domain Name universes without committing the unpardonable sin of propagating bogons. While intricate, this is proceeding smoothly, and by the time you read this, there will be complete TCP/IP connectivity.
Of course, this won't be the end of the story. There never is with networking.
Computing Centre - Rhodes University - Grahamstown
