The Main One Cable is an undersea cable system expected to stretch from Portugal to South Africa with landings along the route in various west African countries. On April 28, 2008, it was announced that Main Street Technologies has awarded a turnkey supply contract for the Main One Cable System to Tyco Telecommunications.

The cable system is expected to span 14,000 km and provide additional capacity for international and Internet connectivity to countries between Portugal and South Africa on the west coast of Africa. The submarine cable project is designed in two phases, both of which are scheduled for completion in May 2010. The dual fiber pair, 1.28-Tbit/s, DWDM project will connect Nigeria, Ghana, and Portugal in Phase 1 with onward connectivity through Portugal to Europe, Asia and the Americas. The Phase 1 cable system will span 6,900 kilometres. Additional connectivity extending to Angola and South Africa will occur in the second phase of the project.

Main One will provide international capacity into a region that has experienced explosive growth in tele-density in recent years, but which remains constrained with respect to access to international cable capacity for global connectivity. The system is being developed by Main Street Technologies headquartered in Lagos, Nigeria. An October 10, 2008 press release states that the desk top study and engineering for the system has been completed.