IA.L2-3.5.5 Identifier Reuse

CMMC Practice IA.L2-3.5.5 – Identifier Reuse: Prevent the reuse of identifiers for a defined period.

Links to Publicly Available Resources

Discussion [NIST SP 800-171 R2]
Identifiers are provided for users, processes acting on behalf of users, or devices (IA.L1-3.5.1). Preventing reuse of identifiers implies preventing the assignment of previously used individual, group, role, or device identifiers to different individuals, groups, roles, or devices.

Further Discussion
Identifiers uniquely associate a user ID to an individual, group, role, or device. Establish guidelines and implement mechanisms to prevent identifiers from being reused for the period of time established in the policy.