The ABCs of Internet protocol

Feb. 2, 2007
This document defines TCP/IP and other topics related to the IP portion of the TCP/IP stack as it applies to control networks, including data encapsulation, routers and hosts, IP addressing and the IP header.
From Contemporary Controls

The IP is responsible for the end-to-end delivery of datagrams over an Internet. It also provides host and network addressing and the means for fragmenting datagrams into manageable packets. IP is a routable protocol and much of its complexity is due to its ability to route packets directly within a local network or indirectly through routers. Routers are not ideal for a control network since they reduce determinism and increase data latency.

Still to accept TCP as a transport layer for an Ethernet control network requires acceptance of IP as well. By understanding the limitations of IP, a control network can still be designed using the TCP/IP family of protocols. This is especially true if the control network is restricted to that of a private or local network.