While SINA may be used to protect all information in companies and critical infrastructure, a key application scenario with SINA is the transmission, processing and saving of officially classified information (CI). The handling of CI is subject to special legal requirements that cover the IT systems used to process CI. SINA products are available with security mechanisms of different strengths depending on the classification. In the SINA product designations, the last letter indicates the maximum classification for which the relevant product is permitted to process CI:

• S for processing up to VS-NUR FÜR DEN DIENSTGEBRAUCH (VS-NfD)
• E for processing up to VS-VERTRAULICH
• H for processing up to GEHEIM

For example, a SINA Workstation S is generally only permitted to process CI in the classification VS-NfD, while a SINA Workstation H can process VS-NfD and VS-VERTRAULICH and GEHEIM. SINA products in the E and H variants are available in addition to the security mechanisms mentioned above, e.g. the open-source BIOS alternative coreboot for protecting boot integrity, mechanisms for detecting manipulation attempts or emissions-protected housings for preventing compromised electromagnetic emissions.

Many SINA products are not only available in versions for protecting German CI, but also in versions for protecting CI of the European Union (EU) and NATO.