Pei Zhiyong, 36, is a cybersecurity specialist at Qihoo 360 and head of 110.#, a website set up to tackle online and offline fraud.

I've been working in internet-related jobs since graduating from college with a major in multimedia telecommunications, but it was an incident six years ago that made me want to take on online fraud.

In 2010, my two air-conditioners at home broke. After searching online, I found a repair company that sent over some workmen. The company appeared professional, but I was surprised when the workmen asked for more than 4,000 yuan ($615) upfront to carry out the repairs.