With IPHost Network Monitor you can run simple snmp requests against a Cisco device in your network.
cieIfContextName
cie If Context Name
1.3.6.1.4.1.9.9.276.1.1.2.1.8
The ContextName denotes the interface 'context' and is used to logically separate the MIB management. RFC 2571 and RFC 2737 describe this approach. When the agent supports a different SNMP context, as detailed in RFC 2571 and RFC 2737, for different interfaces, then the value of this object specifies the context name used for this interface.
Back to CISCO-IF-EXTENSION-MIB MIB page.
IPHost Network monitor allows you to monitor cieIfContextName 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.