Port Connection Permissions?

Previously, connecting MS Access via ODBC to PostgreSQL dB running on NAS required "port forwarding" permissions set on Router. However, Heidi Portable connection to same dB, same network seems to bypass the Router port forwarding permissions...

Is this by design or some sort of security defect?

What do you mean by "previously" - in an older build? Which build then was it?

However, HeidiSQL does not do nothing with bypassing some port forward. Probably you are using a different port in HeidiSQL than in your ODBC connection?

By previously I meant with MS Access, before using Heidi.

Same 5432 port. In fact, just tried connecting direct to PostgreSQL via ODBC Setup and it definitely fails because of Router intervention based on port forwarding for port 5432 not allowed.

Heidi Portable clearly succeeds and appears to SQL work as expected...