With IPHost Network Monitor you can run simple snmp requests against a Cisco device in your network.
cGgsnExtSubscriberTid
cisco Gateway GPRS Support Node Ext Subscriber Tid
1.3.6.1.4.1.9.9.647.1.1.18.1.2
This object indicates a human readable string representing the Tunnel identifier of the Subscriber/PDP context in GGSN.
Back to CISCO-GGSN-EXT-MIB MIB page.
IPHost Network monitor allows you to monitor cGgsnExtSubscriberTid on Cisco device via the SNMP protocol. Download IPHost Network Monitor (500 monitors for 30 days, 50 monitors free forever) to start monitoring Cisco wireless switches right now.