With IPHost Network Monitor you can run simple snmp requests against a Cisco device in your network.
x21portType
x21port Type
1.3.6.1.4.1.351.110.5.1.1.1.3.1.1.8
This represents port type. The processing of the frames depends on the type of the port.
Back to CISCO-WAN-FR-X21-MIB MIB page.
IPHost Network monitor allows you to monitor x21portType 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.