Siemens SIMATIC ET 200pro Operating Instructions Manual page 62

Properties of the access levels
Each access level allows unrestricted access to certain functions without entering a
password, e.g. identification using the "Accessible devices" function.
The CPU's default setting is "No restriction" and "No password protection". In order to protect
access to a CPU, you must edit the properties of the CPU and set up a password. In the
default access level "Full access (no protection)", every user can read and change the
hardware configuration and the blocks. A password is not set and is also not required for
online access.
Communication between the CPUs (via the communication functions in the blocks) is not
restricted by the access level of the CPU, unless PUT/GET communication is deactivated in
the "No access" (complete protection) access level.
Entry of the right password allows access to all the functions that are allowed in the
corresponding level.
Note
Configuring an access level does not replace know-how protection
Configuring access levels offers a high degree of protection against unauthorized changes
on the CPU via network access. Access levels are used to restrict the rights to download the
hardware and software configuration to the CPU. However, blocks on the SIMATIC memory
card are not write- or read-protected. Use know-how protection to protect the code of blocks
on the SIMATIC memory card.
Behavior of functions with different access levels
The STEP 7 online help includes a table listing the online functions available in the various
access levels.
CPU 1516pro-2 PN (6ES7516-2PN00-0AB0)
Operating Instructions, 11/2019, A5E35873416-AC
7.2 Configuring access protection for the CPU
Protection
61