The material in this section is drawn from Coffman and Odlyzko (1998, 2000).
The International Telecommunications Union (ITU) database provides estimates of telephone traffic for 207 countries for 1997-98, which total 2.5 x 1012 minutes per year. Adding in an estimate for the missing countries brings us to 7.5 x 1012 minutes per year, or roughly 600,000 terabytes per month. Compression would reduce storage requirements by a factor of 6 to 8.
The US accounts for about 250,000 terabytes per month, of which roughly a third is modem calls.
We have somewhat better
estimates for long-distance traffic in the US, including voice, Internet,
public data networks and private lines.
| Table 1: Traffic on U.S. long distance networks in terabytes, year-end 1999. | |
Network |
Traffic (terabytes/month) |
| US voice | 48,000 |
| Internet | 10,000 - 16,000 |
| Other Public Data Networks | 2,000 |
| Private Line | 5,000 - 8,500 |
Notes
- Internet traffic has, on average, been doubling every year for 30 years, though the growth rates varied significantly during that period.
- The current rate of growth of Internet traffic is roughly 100% per year.
- By 2002 data traffic will surpass phone traffic.
- Residential Internet use in the US is growing at about 30% a year. When residential users switch to broadband, the total volume of data accessed increases by a factor of 5-10. As residential broadband grows, traffic should approach the 100% per year growth rate.
- Internal corporate (intranet) traffic is growing at about 30% per year, but corporate traffic to the public Internet is growing at 100% per year.
- According to Peter Davidson, of Davidson Consulting, about 300 billion seconds of fax transmissions take place annually. At 45 seconds per page, this means 400 billion pages per year are faxed. At 15 Kb per page, this comes to around 6,000 terabytes of fax information per year.
- Internet growth: Is there a "Moore's Law" for data traffic?, K. G. Coffman and A. M. Odlyzko, 2000. [Abstract] [PostScript] [PDF] [LaTeX]
- The size and growth rate of the Internet, K. G. Coffman and A. M. Odlyzko, First Monday 3(10) (October 1998), http://firstmonday.org/. [Abstract] [PostScript] [PDF] [LaTeX] [First Monday version]
- The Worldwide Fax Traffic Statistical Market Review and Forecast, 1997-2002, Peter Davidson, [Link to Report]