| Abbreviation | Definition |
|---|---|
| QCM | Query Certificate Manager |
| QH | Quick Hack |
| QKD | Quantum Key Distribution |
| QKG | Quantum Key Generation |
| QOP | Quality Of Protection |
| QPR | Quicken Password Recovery |
| QPRK | Quicken Password Recovery Key |
| QPSK | Quadrature Phase Shift Keying |
| QRST | Quick Response Security Training |
| QRT | Quick Response Team |
| QSECOFR | SECurity OFficeR on IBM eServer iSeries |
| QXR | Quick Access Recording |
| QXS | Quick Access |
| R | Reencoding |
| RA | Registration Authority |
| RA | Registry Agent |
| RA | Review Access |
| RAB | Remote Alarm Box |
| RAM | Remote Authorization Mechanism |
| RAN | Registration Access Number |