IP Routing Fundamentals

The Internet's Address Architecture

The Internet's address architecture is implemented in IP. IP's original addressing scheme dates back to the early days of networked computing. At the time, the Internet itself was little more than a semi-public network that interconnected a few dozen universities, research organizations, and government bodies. Each of these entities that connected to the Internet had limited networked computing infrastructures. Typically, these infrastructures consisted of little more than a mainframe computer or a handful of UNIX-based minicomputers. PCs had yet to coalesce into a usable format, and local-area networks (LANs) were in their infancy. Therefore, an internetwork did not require a robust architecture.

The original ...