With IPHost Network Monitor you can run simple snmp requests against a Cisco device in your network.
c3gImei
Cisco 3G Imei
1.3.6.1.4.1.9.9.661.1.3.1.1.2
International Mobile Equipment Identifier (IMEI), a unique 15 or 17 digit code used to identify an individual mobile station to a GSM or UMTS network.
Back to CISCO-WAN-3G-MIB MIB page.
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