With IPHost Network Monitor you can run simple snmp requests against a Cisco device in your network.
c3gGsmPacketSessionStatus
Cisco 3G Gsm Packet Session Status
1.3.6.1.4.1.9.9.661.1.3.3.2.1.1
This object indicates Packet Data Protocol (PDP) session status of the profile. Active when the call is established and PDP context has become active.
Back to CISCO-WAN-3G-MIB MIB page.
IPHost Network monitor allows you to monitor c3gGsmPacketSessionStatus 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.