Rockwell Automation 842E EtherNet/IP Absolute Encoder User Manual - Manual (Page 15)

Rockwell Automation Publication 842E-UM001A-EN-P May 2012 7
Chapter
3
EtherNet/IP overview
Ethernet Industrial Protocol (EtherNet/IP) is a frame-based computer
networking technology for local industrial area networks. It follows the seven
layers of the Open Systems Interconnection model:
Use of the Common
Industrial Protocol EtherNet/IP implements the Common Industrial Protocol (CIP), the
application layer protocol specified for EtherNet/IP.
EtherNet/IP uses the CIP on the process layer. Similarly, as, for example, FTP is
used for the transfer of files, this protocol is used for process control. The 842E
encoder meets the requirements of the EtherNet/IP protocol according to IEC
61784-1 and those of the encoder profile.
The encoder is an I/O adapter in the EtherNet/IP. It receives and sends explicit
and implicit messages either cyclic or on request (polled).
OSI Model
Host Layers
Layer Function
7. Application Network process to application
6. Presentation Data, encryption
5. Session Inter-host communication
Explicit and implicit messaging
4. Transport Flow control, TCP/UDP
Media
Layers
3. Network Internet protocol, logical addressing
2. Data Link Physical addressing
1. Physical Media, signal and binary transmission, peer-to-peer, multicast, unicast
IP
UDP TCP
HTTP FTP CIP
Ethernet
Process layer
Communication
layers
Explicit messagin g Implicit messaging
Physical layer