IP addressing and the DW4020
their TCP limits, vastly increasing the overall throughput. This technique is also known as TCP spoofing.
IP provides a method of constructing a network of networks where computers and networks made by different manufacturers and conforming to different standards can exchange information. The IP is layered on top of
The Internet Assigned Numbers Authority (IANA) assigns ranges of IP addresses to Internet Service Providers (ISPs), who assign ranges to organizations, who are their customers. The organizations, in turn, assign individual numbers within that range to each of their networked computers.
In this way, every computer on a network, (each computer on a network may also be referred to as a "host") is assigned a unique number that identifies it and its network. Actually, the IP address is assigned to the connection rather than to the computer itself. However, it is assumed that the computers are not moved from their respective connections. By convention, these IP addresses are written by converting each byte (8 bits) into a decimal number (0 to 255) and separating each byte by a period as in 192.77.43.4. This format, called dotted decimal notation, is used to enter IP addresses.
It is important to note that IANA defines an "enterprise" as an entity autonomously operating a network using TCP/IP and in particular determining the addressing plan and address assignments within that network. Thus, in the context of TCP/IP, installing networks or DW4020s, or assigning IP addresses, the term enterprise refers to an organization defined in this way.
As an example of Internet address assignment, a small business owner with four networked computers might apply to IANA or its ISP for a “class C” network. In the IP address for a class C network the first three bytes identify the network and the last byte identifies the individual computer. The business owner is assigned the numbers 192.77.43.*, where * represents a “wild
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Appendix B • The Internet and the DW4020
