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See https://spectrum.ieee.org/tech-talk/telecom/internet/undersea-cable-repairs-south-africa for a very full discussion, also also early reports from https://mybroadband.co.za/news/internet/336416-how-south-africas-internet-survived-cable-breaks.html and the aftermath at https://mybroadband.co.za/news/internet/336426-slow-internet-speeds-in-south-africa-at-least-12-more-days.html.
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| SAT3 (RFS 2002 April) | WACS (RFS 2012 May) | ACE (RFS 2012 December) | Equiano (RFS 2021) |
|---|---|---|---|
 |  |  |  |
Cables going East to Europe
| EASSY RFS 2010 July | |
|---|---|
 |
Cables going East to India and Malaysia are shown below.
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The first step occurred between 08:00am and 09:00am Jan 14th, the second step between 07:00am and 08:00am Jan 16th (both times are GMT). I can find no evidence of a failure on January 14th, however it sure looks like there was one. On further inspection, it appears that this step only appears for the TENET target site (see below for the minimum RTTs in msec measured each hour (0 1 ...) from SLAC to the target (Remote-Site) on Jan 14th, 2020), and thus is not related to the cable problems. This can be seen more clearly in the plot below. The spreadsheets are available here.
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N.b. two sites (www.bos.gov.ls and www.dut.ac.za) do not appear to have been affected on January 16th or in the daily plots. Maybe they were not using SAT3 or WACS, for example maybe they were using ACE. According to ieee "TENET restored its overseas connections by switching to an alternative 80-gigabit-per-second service on the SEACOM and EASSy cables on Africa's east coast. "The latency ... increased due to this failover, but there are currently no reported issues of this being detrimental to connectivity," a representative of TENET said on 30 January." The impact on the PingER measurements from SLAC was that the minimum RTT went from ~280ms to 355ms.
One can also look at the various statistics for both Average RTT, losses and minimum RTTs, see below (the spreadsheet is seen here). The Average and Losses are heavily influenced by the congestion. The minimum is mainly influenced by the route change or change in the distance of the cable route. Also note that the impact on the minimum RTT is not seen until Jan 17th since some of the PingER January 16 measurements were made before the change of cables used. It is also worth noting as reported in ieee "TENET restored its overseas connections by switching to an alternative 80-gigabit-per-second service on the SEACOM and EASSy cables on Africa's east coast. "The latency ... increased due to this failover, but there are currently no reported issues of this being detrimental to connectivity," a representative of TENET said on 30 January."
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