With IPHost Network Monitor you can run simple snmp requests against a Cisco device in your network.
tn3270sIpTable
tn3270s Ip Table
1.3.6.1.4.1.9.9.54.1.4.1
A list of IP to LU mapping entries
Back to CISCO-TN3270SERVER-MIB MIB page.
IPHost Network monitor allows you to monitor tn3270sIpTable on Cisco device via the SNMP protocol. Download IPHost Network Monitor (500 monitors for 30 days, 50 monitors free forever) to start monitoring Cisco switches right now.