Comcast reached a long-term agreement with Level 3 Communications that provide inter-city and metro dark fiber as part of Comcast's extension of its fiber footprint. Comcast's backbone is principally based on 20-year dark-fiber IRU's (indefeasible rights of use) from Level 3 and other sources. The new agreements currently total over 19,000 route miles, and cover 95% of Comcast's national footprint. The initial cost of the network, including fiber capacity and routing and optical equipment, is expected to involve approximately $100 million of capital....