| Abbreviation | Definition |
|---|---|
| SME | Short Message Encryption |
| SMEK | Short Message Encryption Key |
| SMIME | Secure Multi-purpose Internet Mail Extensions |
| SMK | System Multipurpose Key |
| SMKS | Single Master Key Scheme |
| SMX | Server Macro eXpansion |
| SNAP | Secure Network Access Platform |
| SNAP | System Network Advanced Protection |
| SNF | Single Network Firewall |
| SNLT | Speed Negotiation Lock Time |
| SO | Sign Out |
| SOAP | Secure Overlay Access Point |
| SOC | Security Operations Center |
| SORB | Secure Object Request Broker |
| SORBS | Spam and Open Relay Blocking System |
| SOSA | Spin Off Sub-Account |
| SP | Secure Proxy |
| SP | Security Potential |
| SPAM | Scanning Probe Array Memory |
| SPAP | Shiva Password Authentication Protocol |