Is it possible to use PGP encryption for XCOM transfers between a mainframe running XCOM for z/OS 12.0 and a Windows server running XCOM for Windows 11.6?
XCOM supports data encryption between OS platforms via SSL/TLS but currently has no built-in support for PGP (Pretty Good Privacy).
Data Encryption Using SSL/TLS
Address Security Requirements
From reading more about PGP (Wikipedia - Pretty Good Privacy) and its differences with SSL/TLS (Information Security Stack Exchange - Public keys on OpenSSL vs PGP?), using PGP is popular with emails and its way to handle certificates is more suited for emails.
Therefore with those explanations, SSL/TLS looks like the right choice for file transfers, client/server and bi-directional.
If PGP is still required then manually coding XCOM pre/post processing exits on both sides of the transfer to do PGP encryption/decryption might be an option, but the effort required to do that is unknown.
To request PGP support to be added to the XCOM product in the future please create a new Idea on the Broadcom Community Ideas under category "XCOM Data Transport".