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Acronyms and initialisms
Look up acronyms used in the wiki and follow the relevant topic when you need more detail.
Sources and scopeSource record 25 August 2026
Technical source record: 25 August 2026. Check the linked documentation for current product requirements.
Common expansions in this knowledge base; vendors and jurisdictions may reuse abbreviations differently.
On this page
Overview#
| Term | Expansion | Context note |
|---|---|---|
| AAA | Authentication, Authorisation, and Accounting | Network/application access control functions |
| ACU | Access Control Unit | Access controller; product boundaries vary |
| ACS / PACS | Access Control System / Physical Access Control System | PACS avoids confusion with logical access, but also has other industry meanings |
| AHJ | Authority Having Jurisdiction | Applicable code/regulatory authority |
| AMQP | Advanced Message Queuing Protocol | AMQP 1.0 is distinct from the older 0-9-1 protocol family |
| API | Application Programming Interface | Contract may be public, partner only, or private |
| ASDU | Application Service Data Unit | IEC telecontrol message unit; type, cause, address, quality, and time context matter |
| BLE | Bluetooth Low Energy | Radio/link foundation used by many mobile credentials |
| BMS / BAS | Building Management / Automation System | Building control platforms and field networks |
| CA | Certification Authority | PKI issuer and trust role |
| CAP | Common Alerting Protocol | OASIS emergency/public warning message format; regional profiles apply |
| CCTV | Closed Circuit Television | Historical/common term; modern video is often IP and interconnected |
| CID | Contact ID | Alarm event format associated with ANSI/SIA DC05 |
| CORS | Cross Origin Resource Sharing | Browser policy; not an API authorisation control |
| CoAP | Constrained Application Protocol | REST like protocol for constrained nodes and networks |
| CRC | Cyclic Redundancy Check | Error detection, not cryptographic integrity |
| CSR | Certificate Signing Request | PKI enrollment artifact |
| CTAP | Client to Authenticator Protocol | FIDO protocol between a platform/client and external or platform authenticator |
| DTMF | Dual Tone Multi Frequency | Used by legacy alarm/telephony signaling |
| E2EE | End to End Encryption | Endpoints and key ownership must be explicitly defined |
| EAP | Extensible Authentication Protocol | Framework used by 802.1X and related access methods |
| EDXL | Emergency Data Exchange Language | OASIS family including the Distribution Element envelope |
| EOL / EOS | End of Life / End of Support | Vendor definitions and dates differ |
| FOV | Field of View | Camera coverage, lens, mounting, and scene property |
| GPIO | General Purpose Input/Output | Electrical interface; validate levels and isolation |
| GOOSE | Generic Object Oriented Substation Event | IEC 61850 fast multicast event mechanism; protection use is high impact |
| gPTP | Generalized Precision Time Protocol | IEEE 802.1AS profile of PTP for time sensitive networks |
| HMI | Human to Machine Interface | Operator interface in OT/building environments |
| IAM | Identity and Access Management | Human/workload identity governance |
| IDS / IPS | Intrusion Detection / Prevention System | Qualify cyber/network versus physical intrusion context |
| IGMP | Internet Group Management Protocol | IPv4 multicast membership management |
| IoT | Internet of Things | Broad category, not a security or interoperability guarantee |
| JWT | JSON Web Token | A token representation; validation profile and authorisation remain essential |
| KMS | Key Management System | May manage cryptographic keys but not all certificate lifecycle |
| LDAP | Lightweight Directory Access Protocol | Directory access protocol; commonly secured with TLS/SASL profiles |
| LPR / ANPR | License/Automatic Number Plate Recognition | Regional terminology for vehicle plate recognition |
| LwM2M | Lightweight Machine to Machine | OMA device management/service enablement profile commonly using CoAP |
| MLD | Multicast Listener Discovery | IPv6 multicast membership management |
| MMS | Manufacturing Message Specification | ISO 9506 service/protocol used by IEC 61850 client/server mappings |
| mTLS | Mutual TLS | Both peers authenticate using certificates during TLS |
| NTS | Network Time Security | Security mechanism for NTP |
| NVR | Network Video Recorder | Recording appliance/service; capabilities vary |
| OSDP | Open Supervised Device Protocol | SIA access peripheral/controller protocol |
| OSCORE | Object Security for Constrained RESTful Environments | End to end CoAP message protection across selected intermediaries |
| OT | Operational Technology | Systems monitoring or controlling physical processes |
| PACS | Physical Access Control System | Also used elsewhere for picture archiving; qualify context |
| PII | Personally Identifiable Information | Legal definitions differ; use local privacy terminology too |
| PIN | Personal Identification Number | A knowledge factor; storage, retries, duress, and privacy require policy |
| PKI | Public Key Infrastructure | Roles, policy, issuance, trust, revocation, renewal, custody |
| PLC | Programmable Logic Controller | Industrial controller, potentially safety/availability critical |
| PoE | Power over Ethernet | IEEE 802.3 power delivery family; budget and cabling matter |
| PSIM | Physical Security Information Management | Integration/orchestration/operator workflow platform category |
| PTP | Precision Time Protocol | IEEE 1588 time synchronisation family |
| RADIUS | Remote Authentication Dial In User Service | Common AAA protocol for network access |
| REX / RTE | Request to Exit | Input/sensor/button used in egress sequence; not proof a person exited |
| RIST | Reliable Internet Stream Transport | VSF media contribution profile family |
| RTCP | RTP Control Protocol | Reception, timing, and participant/control information for RTP |
| RTP | Real time Transport Protocol | Real time media/data packet transport |
| RTSP | Real Time Streaming Protocol | Media session control, not the media transport itself |
| SDP | Session Description Protocol | Describes media sessions; does not negotiate trust by itself |
| SAML | Security Assertion Markup Language | XML based enterprise federation; assertion validation and local role mapping are separate |
| SCIM | System for Cross domain Identity Management | HTTP based identity provisioning schema/protocol family |
| SCL | Substation Configuration Language | IEC 61850 engineering/configuration representation; protect as sensitive change controlled input |
| SIEM | Security Information and Event Management | Security telemetry/correlation platform |
| SIP | Session Initiation Protocol | Multimedia session signaling, common in intercom/voice |
| SNMP | Simple Network Management Protocol | Prefer SNMPv3 security model where supported |
| SRTP | Secure Real time Transport Protocol | Cryptographic protection for RTP media |
| SRT | Secure Reliable Transport | Project media contribution protocol; not an IETF standard |
| SSE | Server Sent Events | One way HTTP event stream to a client |
| SV | Sampled Values | IEC 61850 multicast sampled measurement mechanism |
| TLS | Transport Layer Security | Authenticated encrypted transport when validation is configured correctly |
| UWB | Ultra Wideband | Radio/ranging technology used in some presence/mobile systems |
| VMS | Video Management System | Video device/media/user/event management platform |
| VLAN | Virtual LAN | Segmentation mechanism, not a complete trust boundary by itself |
| VPN | Virtual Private Network | Protected network path; does not replace application authorisation |
| WebAuthn | Web Authentication | W3C public key credential API used with FIDO authenticators |
| WSS | WebSocket over TLS | Common URI scheme for protected WebSocket transport |
| X.509 | Certificate framework | Common certificate format/profile used by TLS and PKI |
| XML | Extensible Markup Language | Structured format; parsers require secure configuration |
Protocol specific abbreviations remain defined on their canonical pages where an expansion would be ambiguous.