With IPHost Network Monitor you can run simple snmp requests against a IBM device in your network.
ifHCInBroadcastPkts
if HC In Broadcast Packets
1.3.6.1.2.1.31.1.1.1.9
The number of packets, delivered by this sub-layer to a higher (sub-)layer, which were addressed to a broadcast address at this sub-layer. This object is a 64-bit version of ifInBroadcastPkts.
Back to ibm_mainframe-Ifmib MIB page.
IPHost Network monitor allows you to monitor ifHCInBroadcastPkts on IBM device via the SNMP protocol. Download IPHost Network Monitor (500 monitors for 30 days, 50 monitors free forever) to start monitoring IBM switches right now.