dancy.2 However, this redundancy has its limits; only a finite number of paths connect any given point to the rest of the system. Also, geography and economics mean that some locations have a high concentration of Internet facilities while others only have few.

New York City, a principal focus of this report, can be thought of as a “superconnected node.” This is largely because the city has a great many Internet users, private data networks, ISPs, and fiber-optic grids.3 For example, more than 600 dial-up ISPs and over 300 digital subscriber line (DSL) providers are listed in the ISP directory Boardwatch for the borough of Manhattan alone. Fiber-optic cables enter and exit Manhattan by way of at least five different rights-of-way. At least 74 U.S. and multinational telecommunications carriers have equipment in New York, either in co-location facilities or in private suites. The city is served by more than 100 international Internet carriers, and it has direct links with 71 countries.4

Connected to the Internet through the long-haul fiber networks of several major carriers, New York City is also a major interconnection point for these carriers.5 Interconnection is for the most part done at one of several key “carrier hotels”—buildings in which carriers lease space in order to link with other carriers located in the same building. Internet providers connect with each other through private connections at the carrier hotels, either directly through Internet exchange points such as the New York Internet Exchange (NYIX) or indirectly through transit providers. Most transatlantic telecommunication cables landing along the New Jersey/New York coastline are “backhauled” to one of the Manhattan


The redundancy and distributed character of the Internet clearly echo the design contemplated in Paul Baran’s seminal studies of packet networks at RAND. The series, together with brief commentary, is available online at <http://www.rand.org/publications/RM/baran.list.html>.


The Lower Manhattan Telecommunications Users’ Working Group (LMTUWG. August 2002. Building a 21st Century Telecom Infrastructure: Lower Manhattan Telecommunications Users’ Working Group Findings and Recommendations) reports six physically distinct fiber networks in Lower Manhattan (AT&T, Con Edison Communications, MCI WorldCom, Metromedia Fiber Network, Time Warner, and Verizon). Information supplied to the committee by Anthony Townsend indicates more than 40 providers of fiber in Manhattan, not all of which are physically distinct (because of sharing and resale by providers).


Telegeography, Inc. October 2001. Telegeography 2002: Global Statistics and Commentary. Washington, D.C. Executive summary available online at <http://www.telegeography.com/products/books/pg/pdf/pg2002_exe_sum.pdf>.


In addition to New York City, Washington, D.C., stands out on the East Coast of the United States as having a high concentration of Internet facilities. Several Internet service providers maintain network-control and data centers near Washington, D.C., and in Northern Virginia. Thus, in most ISP networks, the New York City-to-Washington, D.C., corridor contains the largest number of circuits.

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