Johannesburg · South Africa

Johannesburg's peering weight sits in one exchange. NAPAfrica IX Johannesburg carries 543 participants, more than twice the 206 at JINX, and the other three exchanges account for 49 between them. Colocation is concentrated the same way. The Teraco Johannesburg Campus lists 390 networks, while the Bredell campus lists 22, OADC Parklands 21 and Equinix JN1 9. No South African mobile operator appears in the carrier list for this city, so the registry does not record whether the country's mobile networks peer at these exchanges.

An address that a database places in Johannesburg may not be a device in Johannesburg. Operators announce address blocks from a registry record, and that record carries whichever address the operator filed for the range, often a head office rather than the site the traffic comes from. Mobile networks compound this because handset traffic leaves through a small number of gateways, so a phone on the coast can present an address a database reads as Johannesburg. Geolocation providers follow the operator's published location and update when the operator does.

Someone checking an address here is better off reading the routing data. Look at the origin ASN on the specific prefix and the netname on the registry object, then set that against the 798 exchange participants and 458 facility networks Johannesburg records. A prefix announced by a fixed network inside the Teraco campus behaves differently from one announced by a mobile operator, even when both resolve to the same city string.