Siemens SIMATIC ET 200AL - Page 711

Communications services
3.2 Communications protocols and port numbers used for Ethernet communication
Communication
Function Manual, 12/2017, A5E03735815-AF
25
Protocol
Port number
(2) Link layer
(4) Transport layer
Function
Description
OUC
1
Open User Com-
munication
and
Secure OUC
1 ... 1999
can be used
to limited
extent
2
(4) TCP
(4) UDP
Open User Communi-
cation
(TCP/UDP)
Secure Open User
Communication (TLS)
OUC instructions provide connection
establishment, connection termination
and data transfer based on the socket
layer.
2000 ...
5000
Recom-
mended
5001 ...
49151
can be used
to limited
extent
2
IGMPv2
Internet Group
Management Pro-
tocol
Not relevant (3) Network layer Internet Group Man-
agement Protocol
Network protocol for the organization of
multicast groups.
Reserved 49152 ...
65535
(4) TCP
(4) UDP
- Dynamic port area used for active con-
nection end point if the application does
not determine the local port number.
1
Note: The open communication provides direct access to the UDP/TCP for the user. The user is responsible for observ-
ing the port restrictions/definitions of the IANA (Internet Assigned Numbers Authority).
2
Do not use ports for OUC, which are already used by other protocols
.