With IPHost Network Monitor you can run simple snmp requests against a Cisco device in your network.
cwspAbrCallStartTime
cwsp Abr Call Start Time
1.3.6.1.4.1.351.140.1.2.9.1.1.13
The start time of the ABR call. This is the timestamp when the Setup Message (or Add Party Message) was first received on this interface.
Back to CISCO-WAN-SVC-MIB MIB page.
IPHost Network monitor allows you to monitor cwspAbrCallStartTime on Cisco device via the SNMP protocol. Download IPHost Network Monitor (500 monitors for 30 days, 50 monitors free forever) to start monitoring Cisco wireless switches right now.