This read-write value sets the GARP hold timer, in centiseconds, for a port, controlling how long the port delays before transmitting a GARP PDU to combine multiple registration events into one message. An admin tunes this to reduce GARP protocol chatter on busy ports by batching registration/deregistration events, at the cost of slightly slower registration propagation. For example, raising this value above its default of 10 on a port with frequent VLAN changes would coalesce more events into fewer GARP PDUs.