China Telecom and Reliance have launched a fiber link between China and India that runs southward (and downard of course) from Tibet. Initially only 20Gbps, the system will supposedly have an initial design capacity of 4.8Tbps. It sounds like no big deal, but have you ever noticed the different roles played by submarine and terrestrial networks in different parts of the world? In North America and Europe, terrestrial cables hook up just about everything on the continent, and the submarine cables hook those networks up to the other continents. Everywhere else, submarine cables hook up countries on the same continent and terrestrial fiber networks often don't cross national boundaries.
So despite the fact that the two countries share a 4000km border, most of the traffic that goes from China to India right now goes out via Hong Kong under the water to Singapore and further under the water to Chennai or some other landing station. Such a lack of terrestrial infrastructure is a structural weakness, one that leaves the internet access of far too many countries without adequate connectivity to handle whatever natural or man-made disaster might happen next. Land networks are more diverse, more easily repaired, and easier to upgrade. Dependence on submarine cables for access to neighboring countries is a relic of colonial days where what one got from the ports was far more important than from border crossings. It is about time that the rising economies of India and China got past it.
Over in Africa they are just now celebrating new submarine cables which will for the first time bring real bandwidth to many countries along the coast, one after another - an entirely different stage in development. Cecil Rhodes tried to run a railroad on that route over a century ago, but didn't make it. Maybe some fiber tycoon will pull it off someday.