With IPHost Network Monitor you can run simple snmp requests against a Cisco device in your network.
cGgsnPlmnEntry
Cisco Ggsn Plmn Entry
1.3.6.1.4.1.9.9.240.1.3.13.1
Entry containing list of home PLMN Ids and the Trusted PLMN Ids.
Back to CISCO-GGSN-MIB MIB page.
IPHost Network monitor allows you to monitor cGgsnPlmnEntry on Cisco device via the SNMP protocol. Download IPHost Network Monitor (500 monitors for 30 days, 50 monitors free forever) to start monitoring Cisco firewalls right now.