Siemens Simatic S7-400 - Page 38

Configuration and operation
4.2 Security recommendations
CP 443-1 OPC UA
38 Operating Instructions, 01/2017, C79000-G8976-C427-02
Protocols
Secure and non-secure protocols
● Only activate protocols that you require to use the system.
● Use secure protocols when access to the device is not prevented by physical protection
measures.
The NTP protocol provides a secure alternative with NTP (secure).
Table: Meaning of the column titles and entries
The following table provides you with an overview of the open ports on this device.
●
Protocol / function
Protocols that the device supports.
●
Port number (protocol)
Port number assigned to the protocol.
●
Default of the port
– Open
The port is open at the start of the configuration.
– Closed
The port is closed at the start of the configuration.
●
Port status
– Open
The port is always open and cannot be closed.
– Open according to configuration
The port is open if it has been configured.
– Open (login, when configured)
As default the port is open. After configuring the port, the communications partner
needs to log in.
●
Authentication
Specifies whether or not the protocol authenticates the communications partner during
access.
Protocol / function
Port number (pro-
tocol)
Default of the port
Port status
Authentication
DHCP
67 (UDP)
Open
Open
No
DCP
93 (UDP) Open Open No
DCE
135 (TCP) Open when the
server is enabled.
Open after configuration (server) Yes, when security is
enabled.
OPC UA server
port
4840 (or individual-
ly confgured)
(TCP)
Open when the
server is enabled.
Open after configuration (server) Yes, when security is
enabled.