We can only pull data from a network device if the device has one or more of the following protocols enabled, preferably SNMP: FTP, HTTP, HTTPS, JetDirect, MOB (Managed Object Browser), SIP, SMTP, SNMP (SNMPv1, SNMPv2 or SNMPv3), SSH, Telnet or WMI. You should:
- Check your VOIP documentation for information on enabling protocols, preferably SNMP.
- Test protocol access with Devicetester, documented here.
- Rescan the VOIP phones, preferably pulling data from the SNMP protocol. Device scanning instructions can be found here.