With IPHost Network Monitor you can run simple snmp requests against a Cisco device in your network.
ccapAppIntfSMTPWriteRequest
Cisco Call Applications Application Interface SMTP Write Request
1.3.6.1.4.1.9.9.146.1.6.20.1.7
Total number of SMTP write requests sent by call applications to this SMTP server.
Back to CISCO-CALL-APPLICATION-MIB MIB page.
IPHost Network monitor allows you to monitor ccapAppIntfSMTPWriteRequest on Cisco device via the SNMP protocol. Download IPHost Network Monitor (500 monitors for 30 days, 50 monitors free forever) to start monitoring Cisco firewalls right now.
