I should have remembered, NANOG prefers to correct things. So here are several estimates about how much IP/Internet traffic is downloaded in a month. Does anyone have better numbers, or better souces of numbers that can be shared? Arbor/Merit/Michigan Internet Observatory: 9,000 PB/month (2009) Minnesota Internet Traffic Studies: 7,500-12,000 PB/month (2009) Cisco Visual Network Index: Total IP: 55,553 PB/month (2013) Fixed IP: 39,295 PB/month (2013) Managed IP: 14,679 PB/month (2013) Mobile Data: 1,578 PB/month (2013) Telegeography via ITU report: 44,000 PB/month (2012) National Security Agency: 55,680 PB/month (2013) Individual providers/countries Australian Bureau of Statistics (AU only) : 184 PB/month (2012) AT&T Big Petabyte report (AT&T only): 990 PB/month (2013) CTIA mobile traffic (US only): 69 PB/month (2011) London School of Economics (Europe only): 3,600 PB/month (2012) TATA Communications: 1,600 PB/month (2013) Historical: NSFNET: 0.015 PB/month (1994)