3.1.6.1 Block Timer Expiry

When the Block timer fires, the enumerator MUST construct a Discover frame by filling the Station List field with entries from the Last-Seen Station List. If there are more entries in the list than will fit in the Discover frame, additional Discover frames MUST be created to hold these additional entries. All Discover frames are then broadcast over the network. Finally, the Last-Seen Station List MUST be cleared.

The DiscoverFrameSent flag MUST be set to TRUE after sending the Discover frames. This triggers the sending of reset frames during shutdown to clean up responder state.

If the enumerator is not satisfied that it has given enough time for all responders to respond, the timer MUST be restarted. How the enumerator determines whether or not enough time has passed can be done in any implementation-specific<10> way. For example, the RepeatBAND algorithm (as specified in section 3.5.6.2) predicts that if the Seen Station List does not grow for three consecutive Block timer expirations, it can be assumed that all responders have reported.

If the enumerator is satisfied that it has given enough time for all responders to respond, it must shut down quick discovery as specified in section 3.1.8.

The enumerator MUST set the Generation Number field in the Discover header to zero, unless the enumerator is also functioning in the Mapper role (as specified in section 3.1.6.1.1).