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Beijing-based Crystal is one of the largest visual technology
application service companies for the global design industry. Its
professional image technology has been used in a large number of
projects, including at the Beijing Olympic Games where it was the
authorized 3D image development company. Crystal¡¦s more than 1500
employees serve customers in Europe, America and the Middle East, and
the company has a service network covering its Beijing headquarters and
branch offices in China¡¦s coastal cities and abroad.
The toughest problem on Crystal¡¦s networks was very low transmission
rates when overseas branch offices downloaded video, audio and image
files from the server in the Beijing headquarters, especially at peak
hours. The average transmission rate was only 9.8kbps and it could take
over an hour to transmit a video file of dozens of megabytes. Employees
were fed up with frequent breakages on their VPN lines, which sometimes
meant transmissions had to be repeated when the network failed just
minutes from the end of a long transmission. The delays and failures
were undermining Crystal¡¦s work schedule.
At the root of the problems were the low-speed ADSL lines used
by overseas branch offices and the shocking latency and packet loss
rates on international Internet links. Real-world tests showed that the
latency from branch offices such as those in Dubai and London to the
Beijing HQ was over 500ms, and the packet loss rate was one to five
percent.
Branch offices in China were also interconnected with the HQ
through VPN lines, so the business in China was similarly affected. |
