I have no doubt their offices are in East London, but that doesn't mean the network isn't in JHB area, which I am pretty sure it is. Besides, I think most of the network is built by Neology and not Sainet themselves. Ie. outsourced.
Doing a traceroute from CT:
Code:
traceroute www.sainet.co.za
traceroute to www.sainet.co.za (41.216.192.115), 30 hops max, 52 byte packets
1 vl305.cr.gw.cpt.za.wa.co.za (196.220.59.129) 1.426 ms 1.621 ms 1.284 ms
2 vl35.er.gw.cpt.za.wa.co.za (41.185.0.38) 2.289 ms 2.104 ms vl34.er.gw.cpt.za.wa.co.za (41.185.0.34) 2.181 ms
3 upstream.vl101.gw.cpt.za.wa.co.za (196.220.59.226) 1.058 ms upstream.vl102.gw.cpt.za.wa.co.za (196.220.59.230) 1.740 ms upstream.vl101.gw.cpt.za.wa.co.za (196.220.59.226) 0.979 ms
4 rrba-ip-hsll-1-gig-1-0-8.telkom-ipnet.co.za (196.43.51.70) 25.388 ms 24.664 ms 24.841 ms
5 ipinx-internet-gw.telkom-ipnet.co.za (196.25.110.46) 26.665 ms 25.102 ms 25.629 ms
6 grzcr01-eth1.neoinx.net (41.216.193.1) 27.725 ms 28.521 ms 27.751 ms
7 saicr02-eth1-212.neoinx.net (41.216.193.170) 28.678 ms 27.225 ms 27.793 ms
8 41-216-192-115.neoinx.net (41.216.192.115) 28.250 ms 29.166 ms 28.426 ms
At hop 4 you can see it enters Rosebank (RRBA = Rosebank according to
http://www.telkom.co.za/attheoffice/products/isdn/business_national_availability_gauteng.html) which is in Johannesburg (again the above link shows 011 as the national calling code) after which it enters the IPINX network (IPINX is also known as Neology according to
www.peeringdb.com), not to mention the latency stays relatively the same after that which means the traffic definitely didn't go to East London...