1990s: High Capacity Backbones

• Backbone capacities increased from 2.5 Gb/s to 100s of Gb/s during the 1990’s

  • Wavelength division multiplexing with 160 waves of 10 Gb/s was commercially available

• Several high-capacity backbones built in the US and Europe

  • Williams, Enron, Global Crossing, 360 Networks

• But not enough traffic to fill the backbones

  • Customers (businesses and homes) not served by high-capacity networks in the “access” network
  • “First-mile” is the bottleneck