With IPHost Network Monitor you can run simple snmp requests against a Cisco device in your network.
cGgsnDefaultAggregEntry
Cisco Ggsn Default Aggregate Entry
1.3.6.1.4.1.9.9.240.1.3.4.1
An Entry contains the IP network prefix which is used to combine the routes of PDP requests for the same network as a single route on the GGSN.
Back to CISCO-GGSN-MIB MIB page.
IPHost Network monitor allows you to monitor cGgsnDefaultAggregEntry on Cisco device via the SNMP protocol. Download IPHost Network Monitor (500 monitors for 30 days, 50 monitors free forever) to start monitoring Cisco optical switches right now.