Zoiper Free is a IAX and SIP softphone compatible with the Asterisk platform as any other SIP or IAX capable system. Zoiper Free Edition features include:
    
     * SIP + IAX/IAX 2 protocols
     * STUN support
     * STUN server per account
     * T.38 fax support
     * Echo cancellation
     * DTMF tones sending
     * DSCP support
     * Support for multiple audio devices
     * Automatic user registration
     * Call transfer
     * Hold function
     * Codecs: GSM, ulaw, alaw, speex, ilbc
     * Adaptive Jitter Buffer
     * Call history
     * Address book
     * Quick dial panel
     * Optional Automatic pop-up window for incoming call
     * Always on top
     * Call logs
     * Voice mail message information
     * Account password encryption
     * Upgrade notification
     * Adjustment of audio device
     * Codecs priority
     * Portable storage compatibility
     * Multilanguage support
    
     Re-branded Zoiper:
    
     * Basic: colours, name and logo of your choice;
    
     * Re-branding with additional development: e.g. changing the language; adding, disabling, removing of menus/options/buttons; adding functionalities;
    
     * Complete: you can go for complete change of the interface and functionality.
     Info about Zoiper OEM can be obtained at zoiper@attractel.com
    
     Zoiper Biz, the advanced version of Zoiper Free, gives more features:
    
     * Native conferencing
     * API
     * TLS/TCP support with SIP
     * TLS with SRTP support
     * g.729 (optional)
     * Mail program plug-in: Outlook integration
     * Callto URL protocol
     * Automatic provisioning (XML)
     * Call forward
     * Auto answer
     * Incoming URL handling
     * Automatic opening of incoming URL
     * Access voice mail message with one button
     * Attended transfer (native)
     * Call recording (Single file recordings)
     * Command line dialing
     * Custom ring tones
     * Open URL on different call events
     * Call history
     * Call transfer
     * Unlimited number of accounts
     * Changeable number of lines (up to 6)
     * More!
    
     Both Zoiper editions may be customized to unique customer requirements.

Related keywords:
   iax
   sip
   iax2
   iax and sip
   tcp
   tls
   srtp
   t.38
   fax
   softphone
   soft phone