ETHERNET • 271
Network communication
Modular I/O System
ETHERNET TCP/IP
ETHERNET layers with TCP/IP compared to the ISO-OSI reference mo-
del
The communication software TCP/IP is superior to ETHERNET. Together
with ETHERNET, TCP/IP represents the typical layer structure.
-
ETHERNET = layer 1 to 4
-
TCP/IP = layer 3 and 4
ISO-OSI-layer
in comparison with
ETHERNET
Tasks
7
Application Layer
Application
= Application software, protocols
and services
- Ensures the compatibility
between applications
6
Presentation Layer
- Data interpretation
5
Session Layer
- Opening and closing sessions
- Communication control
4
Transport Layer
Transport
= Transport Control Protocol
TCP
- Transmission control
3
Network Layer
Internet
= Internet Protocol IP
- Addressing and routing
2
Data Link Layer
Network-Interface
= Packet-Driver
- Frame format
- Medium access control
- Coding and medium access
1
Physical Layer
Hardware
= ETHERNET –Coupler
- Making electrical connection
- Laying down all physical
and mechanical parameters