This notification-only object identifies which pool's network has run out of addresses to allocate, by reporting the combination of the pool's start/stop IP range and subnet mask that is exhausted. This is the field that turns a generic 'pool exhausted' trap into an actionable one, telling the admin exactly which subnet needs its range expanded or its lease times shortened. For example, if this reports a network matching a pool configured for 192.168.5.10-192.168.5.50/255.255.255.0, the admin knows that specific /24's DHCP scope of 40 addresses has been fully consumed and needs attention.