Bibliography

TCP/IP

TCP/IP (German)
Aufbau und Betrieb eines TCP/IP Netzes (Structure and Operation of a TCP/IP Network)
by Kevin Washburn and Jim Evans
Publisher: ADDISON-WESLEY Longmann Verlag

TCP/IP (English)
Illustrated, Volume1 The Protocols
by W. Richard Stevens
Publisher: ADDISON-WESLEY Longmann Verlag

Modbus/TCP

http://www.modicon.com/
http://www.modbus.org

TwinCAT

BECKHOFF Information System
http://infosys.beckhoff.com