User Manual Owner's manual

Rockwell Automation Publication 280E-UM001B-EN-P - July 2012 59
Introduction to EtherNet/IP and Device Level Ring Technology Chapter 3
Introduction to EtherNet/IP
Automation architectures must provide users with three primary services:
• Control services involve the exchange of time-critical data between
controlling devices and I/O devices.
• Networks must provide users configuration capabilities to set up and
maintain their automation systems.
• Automation architecture must allow for collection of data.
EtherNet/IP, provides installation flexibility and leverages commercially available
industrial infrastructure products. It is also compatible with other
communication standards, such as Hypertext Transfer Protocol (HTTP), Simple
Networks Management Protocol (SNMP), and Dynamic Host Configuration
(DHCP).
EtherNet/IP is a CIP adaptation of TCP/IP that fully utilizes the IEEE standard.
The relationship between the TCP/IP and CIP to form EtherNet/IP is shown in
the ISO/OSI 7-layer model is shown in Figure41. The OSI model is an ISO
standard for network communications that define all functions from a physical
layer to the protocol.
Subnet mask An extension of the IP address that allows a site to use a single net ID for
multiple networks.
Switch A network device that cross connects devices or network segments. A switch
provides each sender/receiver the full network bandwidth (2x in full duplex
mode), reduces collisions, and increases determinism.
TCP The transport control protocol is a more reliable but slower transport protocol
than UDP. It is used for explicit (not time critical) messaging in EtherNet/IP.
This Term Means