The first undersea cable to bring high-speed internet access to East Africa has gone live.
The fibre-optic cable, operated by African-owned firm Seacom, connects South Africa, Tanzania, Kenya, Uganda and Mozambique to Europe and Asia.
The firm says the cable will help to boost the prospects of the region's industry and commerce.
The cable - which is 17,000km long - took two years to lay and cost more than $650m.
Seacom said in a statement the launch of the cable marked the "dawn of a new era for communications" between Africa and the rest of the world.
The services were unveiled in ceremonies in the Kenyan port of Mombasa and the Tanzanian city of Dar es Salaam. School benefits
The cable was due to be launched in June but was delayed by pirate activity off the coast of Somalia.
The BBC's Ben Mwangunda in Dar es Salaam says five institutions are already benefiting from the faster speeds - national electricity company Tanesco, communications company, TTCL, Tanzania Railways and the Universities of Dar es Salaam and Dodoma.
The BBC's Will Ross in Nairobi says the internet revolution trumpeted by Seacom largely depends on how well the service is rolled out across the region.
To the disappointment of many consumers, our correspondent says some ISPs (internet service providers) are not planning to lower the cost of the internet, but instead will offer increased bandwidth.
But businesses, which have been paying around $3,000 a month for 1MB through a satellite link, will now pay considerably less - about $600 a month.
The Kenyan government has been laying a network of cables to all of the country's major towns and says the fibre-optic links will also enable schools nationwide to link into high quality educational resources.
But our correspondent says it is not clear whether the internet revolution will reach the villages, many of which still struggle to access reliable electricity.