This paper introduced the production and harmfulness of the metro stray current and the method of the embedded the TCP/ IP protocol microchip linked to Internet, the stray current monitoring system based on embedded TCP/IP protocol microchip is con- structed, and its error rate of communication and precision has been checked by experiment.

It can realize the scene signal gathering finally and carry on the data transfer through the TCP/IP agreement.

The text introduce a intellectualized control system to switch equipment of high and low voltage based on TCP/IP agreement ,it has DSP and LAN91115 composition.

The application of the embedded TCP/IP protocol in network communication;

TCP/IP protocol-based remote metering systems for power plants;

TCP/IP protocol implementation for switching network architecture based on software radio;

The image transmission system depending on embedded TCP/IP;

Design and implementation of TCP/IP in a embedded microcontroller system of data communication;

Application of TCP/IP in Milking Controlling System;

Design of Embedded TCP/IP Protocols;

By analyzing the data from MIB-Ⅱ, the security of network can be monitored from the data link layer, network layer, transport layer and application layer of TCP/IP protocols.

According to the data got from MIB Ⅱ, the security of Ethernet can be monitored from data link layer, network layer, transport layer and application layer of TCP/IP protocols.