With IPHost Network Monitor you can run simple snmp requests against a Cisco device in your network.
cGgsnExtDownstreamByteCount
cisco Gateway GPRS Support Node Ext Downstream Byte Count
1.3.6.1.4.1.9.9.647.1.1.13.1.4
This object indicates the total number of downstream traffic bytes sent in the last sampling period specified by cGgsnExtThruputInterval.
Back to CISCO-GGSN-EXT-MIB MIB page.
IPHost Network monitor allows you to monitor cGgsnExtDownstreamByteCount on Cisco device via the SNMP protocol. Download IPHost Network Monitor (500 monitors for 30 days, 50 monitors free forever) to start monitoring Cisco mobile switches right now.
