I designed and deployed ICTFax as part of our VoIP migration. ICTFax integrates with any SMTP email server and uses a SIP Trunk to send and receive faxes to and from emails. ICTFax requires deploying a working FreeSwitch server and configuring it to work with the ICTFax software.
I’ve contributed several bug fixes to the project. I’ve coded upgrades to the default install to include anonymous fax capability and I have added LDAP integration into the system.
I maintain my own port of ICTFax on my github account