Hi "D"
Perhaps I can clarify, since it was I who was quoted in the original article.
ICASA regulate, however, as far as I know, they do not impose any obligation on Telkom to transit traffic nor do they prevent them from doing so. So this was at Telkom's discretion.
Telkom only introduced the transit amendment agreement last month. Following various providers signing the amendment agreement and lodging with ICASA, the Telkom department handling international interconnects announced new rates and prefixes to their interconnect partners that were going to come into effect from 1 October 2008. On said date, they then removed the block that was preventing these prefixes from being transited in the past.
So why did they only start offering transit recently when they hadn't in the past?
Telkom's response is that this is part of "phase 2" of the VANS interconnection and that it has been in planning for some time.
My belief - and I must warn that this is speculative - is that this was because an increasing number of VoIP providers were negotiating with international carriers to perform their international transit and, in order to make those agreements more commercially viable, were offering those international carriers transit to the entire of South Africa (including Telkom and the mobile networks). This would have created the potential to erode revenue Telkom earns from various foreign carriers.
Commercially, Telkom now stand to lose more from forcing VoIP providers to enter into such interconnect agreements with foreign carriers than they can gain by simply offering transit to the VoIP operators, causing the VoIP operators not to bother with interconnecting with those international carriers.
In short, I believe that it was a simply a case of Telkom responding to commercial pressure at the time that it made most sense, tactically, for them to do so.
Again, speculative... I may be wrong.