With IPHost Network Monitor you can run simple snmp requests against a Cisco device in your network.
agentInterfaceIPNetmask
agent Interface IP Netmask
1.3.6.1.4.1.14179.1.2.13.1.6
IP Netmask of the interface. This is 0 for the virtual interface.
Back to AIRESPACE-SWITCHING-MIB MIB page.
IPHost Network monitor allows you to monitor agentInterfaceIPNetmask on Cisco device via the SNMP protocol. Download IPHost Network Monitor (500 monitors for 30 days, 50 monitors free forever) to start monitoring Cisco routers right now.