1. Cisco Systems Visual networking index, forecast and methodology 2009 http://www.cisco.com
2. Internet traffic growth: sources and implications;Odlyzko;Proceedings of SPIE,2003
3. Minnesota Internet traffic studies (MINTS) http://www.dtc.umn.edu/mints/home.php
4. Australian Bureau of Statistics Internet activity http://abs.gov.au/ausstats/abs@.nsf/mf/8153.0
5. Office of the Telecommunications Authority (OFTA) of the Hong Kong Special Administrative Region Statistics of Internet traffic volume http://www.ofta.gov.hk/en/tele-lic/operator-licensees/opr-isp/s2.html