Firewall - Siemens SIMATIC ET 200AL System Manual

13.1

Firewall

Tasks of the firewall
The purpose of the firewall functionality is to protect networks and stations from outside
influences and disturbances. This means that only certain previously specified
communications relations are permitted.
To filter the data traffic, IPv4 addresses, IPv4 subnets, port numbers or MAC addresses
among other things can be used.
The firewall functionality can be configured for the following protocol levels:
● IP firewall with stateful packet inspection (layer 3 and 4)
● Firewall also for Ethernet "non-IP" frames according to IEEE 802.3 (layer 2)
Firewall rules
Firewall rules describe which packets are permitted or forbidden in which direction.
Communication
Function Manual, 12/2017, A5E03735815-AF
Industrial Ethernet Security with CP 1543-1
13.1 Firewall
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