Fieldbus Communication; Implemented Protocols; Communication Protocols; Ip (Internet Protocol) - WAGO -I/O-SYSTEM 750 Manual

WAGO-I/O-SYSTEM 750
750-882 Media Redundancy ETHERNET Controller
12

Fieldbus Communication

Fieldbus communication between master application and a WAGO fieldbus
coupler/controller based on the ETHERNET standard normally occurs via a
fieldbus-specific application protocol.
Depending on the application, this can be e.g., MODBUS/TCP (UDP),
EtherNet/IP, BACnet/IP, KNXnet/IP, PROFINET, sercos or other.
In addition to the ETHERNET standard and the fieldbus-specific application
protocol, there are also other communications protocols important for reliable
communication and data transmission and other related protocols for configuring
and diagnosing the system implemented in the WAGO fieldbus coupler/controller
based on ETHERNET.
These protocols are explained in more detail in the other sections.
12.1

Implemented Protocols

12.1.1

Communication Protocols

12.1.1.1

IP (Internet Protocol)

The Internet protocol divides datagrams into segments and is responsible for
their transmission from one network subscriber to another. The stations involved
may be connected to the same network or to different physical networks which
are linked together by routers.
Routers are able to select various paths (network transmission paths) through
connected networks, and bypass congestion and individual network failures.
However, as individual paths may be selected which are shorter than other paths,
datagrams may overtake each other, causing the sequence of the data packets
to be incorrect.
Therefore, it is necessary to use a higher-level protocol, for example, TCP to
guarantee correct transmission.
IP Packet
In addition to the data units to be transported, the IP data packets contain a
range of address information and additional information in the packet header.

Table 70: IP Packet

IP Header
The most important information in the IP header is the IP address of the
transmitter and the receiver and the transport protocol used.
Fieldbus Communication 209
IP Data
Manual
1.5.0