This read-write object sets the maximum number of dynamically learned MAC addresses allowed on this port, ranging from 0 to 600 with a default of 600. Admins lower it on ports expected to serve only a handful of devices, like a single desk or a small IP phone and PC combo, so that exceeding the limit triggers a security violation rather than silently learning an unlimited number of MACs. Setting agentPortSecurityDynamicLimit to 2 on an access port would allow only two dynamically learned MAC addresses, such as a phone and a PC daisy-chained through it, before any additional device triggers a violation.