Connectivity Providers Database

From: mlawrie@apies.frd.ac.za (Mike Lawrie) To: netnews@apies.frd.ac.za Date: Sun, 5 May 1996 19:55:57 +0200 (EET) Status of SAIX Upgrade, 5 May 1996 ---------------------------------- It looks as if Telkom has done an upgrade to this link on Saturday 4th May, mid-morning. The highest peak traffic that has been observed is a shade under 500 Kbps. It took a few hours, not minutes, to get to that load, but then not all of the Uninet sites could access that circuit. So presumably only 512 Kbps has been installed, and not the 1024 Kbps that was ordered, promised and assured. Uninetters are better off than they were on Friday, but are nowhere near where they need to be. The FRD will be consulting with lawyers tomorrow (Monday 6th May) in order to find out what options exist for compelling Telkom to install the 1024 Kbps SAIX service together with the upgrade to the Uninet trunk circuits, and to do so immediately. It looks as if Telkom are unwilling or unable to install these upgrades on the basis of the applications submitted in October and November last year (and brought to their attention on many an occasion this year), so if an urgent court order is what it is going to take then it will be obtained. The present load on the (incoming) traffic on the SAIX link is from the sites that use Wits and the CSIR as their hubs, with some "leakage" from other Uninet sites. The sites that use UCT as their hub will be set to route via this ciruit in this coming week. Some fine tuning still needs to be done, but by and large the route is working and Uninet is clawing its way back to providing a reasonable Internet service. The choke router at Wits, which is normally set to limit Wits's access to Uninet to be 148 Kbps (this is at Wits's request), has temporarily been lifted to 2Mbps in order to generate load on the USA circuit, and it is doing this most successfully (thanks to Wits users who presently must be floating in bandwidth :). The choke will be set back to the contracted level in the near future, it is likely to bite Wits users pretty hard, but that is a Wits' decision, not Uninet's. What is likely to happen to many Uninet sites is that the congestion from the USA will shortly move from the limitation of the international circuit to the limitation of the site's access circuit. This congestion will then be seen in poor access to local sites (eg FTP at Stellenbosch, Sabinet). Uninetters can consult with their IT Departments regarding what bandwidth is on their access circuit, and they can see for themselves the load on that access circuit by monitoring the graphs on http://www.frd.ac.za/uninet/sitelinks.html. Most sites connect only at 64 Kbps, very few of them at 128 Kpbs or faster. The precise connectivity can be seen on the diagram on http://www.frd.ac.za/uninet/routers.gif. Here's an ascii diagram that might help to visualise the likely congestion point:- ~~~~~~~~~~~~~~~~~~~ | The Internet, USA | ~~~~~~~+~~~~~~~~~~~ | | <-- 1024 Kbps via SAIX | (well, 512 Kbps but....) +-------+--------+ |Gateway at Wits | +-------+--------+ / | / | <---Uninet Backbone @ 512 Kbps / | (well, actually 256 Kbps, but...) . | . . | . | +-------+-------+ | Uninet Hub | +-+-+-+-+-+-+-+-+ | | | | | | | | | | | | | | <-- Access circuit, typically 64 Kbps . . . . . . | (likely to be the congestion point) . . . . . . | (R12,800/yr/64Kbps to upgrade) | +-------+-------+ | Access router | <-- At a Uninet site +-------+-------+ | /===============+================/ Internal LAN of the Uninet site In principle, it is easy and cheap to increase the access bandwith. Given the go-ahead from the site concerned, Uninet gets Telkom to install a faster circuit from the Uninet site to the Uninet hub, and charges the Uninet site an additional R12,800/yr/64Kbps (which is approximately the Telkom charge for the circuit). Any site that wishes to increase its bandwidth must give the Manager of Uninet the appropriate authority to do so, as well as some official guarantee that the additional charges will be paid. Of course, allow for the length of time that it might take Telkom to do the upgrade of the access circuit.... -- Mike Lawrie, Phone: +27 12 481-4148 Manager:UNINET, Fax: +27 12 349-1179 Foundation for Research Development, P O Box 2600, Pretoria 0001 South Africa