Great Wall of Tech, tough to breach

Foreign net firms are realizing the hard way that success in China takes Herculean efforts

If China's Great Wall was difficult to scale or penetrate for Eurasian nomadic raiders of the past, the Chinese mainland's technology and digital market are posing similar problems to foreign companies now.

In a recent move, Uber decided to end its lone fight in China, and merge its China unit with its bitter rival Didi Chuxing, a Beijing-based transportation network company, after investing about $2 billion in the market in less than two years.