Certificate expiring -> no communication -> Really?

Hi everyone:

I'm just being working on a project involving 2 MTP1500 connected to 3 S7-1500 in which communication between the CPUs and the HMIs seemed not to work. Problem was that, as the communication between the CPU and the HMI involves a security certificate created by the PLC, and the Date/Time on the HMI was still not set, the certificate date was not valid.

So as a general question I raised a Service Support request asking how can this be avoided, as the certificate validity was about 14 years, that may be seen as a lot of time but is no forever. Their answer was that this is how it is, so if I want to keep the PLCs communication with the HMIs the certificates have to be renewed.

But thing is that we usually do not give access to our PLCs for know-how protection and security (my company does industrial boilers) so we are supposed to inform our clients that their PLCs are stopping communication with their HMIs after 14 years? I find this difficult to believe, but the answer from the Service Support was pretty clear that this is how it works.

Have any of you had a problem like this? Is this really as bad as it looks or I am missing something?

Oscar G. Flores

Their answer was that this is how it is, so if I want to keep the PLCs communication with the HMIs the certificates have to be renewed.

But thing is that we usually do not give access to our PLCs for know-how protection and security (my company does industrial boilers) so we are supposed to inform our clients that their PLCs are stopping communication with their HMIs after 14 years? I find this difficult to believe, but the answer from the Service Support was pretty clear that this is how it works.

Have any of you had a problem like this? Is this really as bad as it looks or I am missing something?

No worries.
If the certificates used have expired, the secure connection will continue.
However, to increase the security of your plant, you should update certificates as
soon as the expiration date is reached.

https://support.industry.siemens.com/cs/ww/en/view/109798498