NIST 800-53 REV 5 • SYSTEM AND COMMUNICATIONS PROTECTION
SC-15(4) — Explicitly Indicate Current Participants
Provide an explicit indication of current participants in {{ insert: param, sc-15.04_odp }}.
CMMC Practice Mapping
No direct CMMC mapping
NIST 800-171 Mapping
No direct NIST 800-171 mapping
Related Controls
No related controls listed
Supplemental Guidance
Explicitly indicating current participants prevents unauthorized individuals from participating in collaborative computing sessions without the explicit knowledge of other participants.
Practitioner Notes
When using collaborative computing, every participant in the session must be clearly visible to all other participants. No hidden observers or undisclosed listeners.
Example 1: Configure your Teams or Zoom rooms to display a participant list that all attendees can see. Disable the ability for participants to join anonymously — require named accounts for all meeting attendees.
Example 2: Enable meeting join/leave notifications (audio chimes and visual alerts) in your conferencing platform so everyone is aware when someone enters or exits. Disable the option for attendees to lurk without appearing in the participant list.