This value, ranging from 10 to 100 centiseconds (0.1 to 1 second), sets the MRP (Multiple Registration Protocol) Join timer for a port, controlling how frequently the switch retransmits registration declarations to ensure VLAN or multicast group membership propagates reliably across the network. An administrator tunes this timer when adjusting how quickly MRP-based VLAN/group registrations converge across a topology, with a shorter join time speeding up propagation at the cost of slightly more protocol traffic. With the default value of 20 centiseconds, the switch retransmits MRP join declarations roughly every fifth of a second on ports using the default timing.