With IPHost Network Monitor you can run simple snmp requests against a Cisco device in your network.
portCopySource
port Copy Source
1.3.6.1.2.1.16.22.1.3.1.1.1
The ifIndex of the source which will have all packets redirected to the destination as defined by portCopyDest.
Back to SMON-MIB MIB page.
IPHost Network monitor allows you to monitor portCopySource on Cisco device via the SNMP protocol. Download IPHost Network Monitor (500 monitors for 30 days, 50 monitors free forever) to start monitoring Cisco multiplexers right now.