This read-write integer, ranging 5 to 900 seconds, sets the rate at which CDP PDUs are sent on all CDP-enabled ports. An administrator tunes this to balance how quickly topology changes are advertised against the overhead of frequent CDP traffic on the network. For example, in a stable, well-documented network, the admin might raise this value toward the 900-second maximum to reduce unnecessary CDP chatter, while a dynamic lab environment might use a lower value for faster neighbor discovery updates.