Today, the Internet is chipping away at the periphery of the private network services that make up global networks. As the Internet continues to evolve, more of corporate IT's global traffic will be routed over it.

Although the Internet is likely to play a bigger role in corporate networks, it isn't likely to replace private network services anytime soon. Among the limitations: a lack of QoS capabilities needed for multimedia applications such as videoconferencing, and relatively weak security.

Faster, Better, Cheaper

The Internet is not only a better network than it was a few years ago, but it continues to improve rapidly.

"The Internet is larger than it was five years ago by a factor of at least five," says Vinton Cerf, co-inventor of the Internet and chief Internet evangelist at Google Inc. "It continues to function reliably, and the underlying systems have higher absolute capacity."