If you do not like Skype, you may find competitive products
for free instant VOIP communication.
1. Ekiga
Ekiga, formerly GnomeMeeting, is a free, open source,
multi-platform softphone, instant messaging, and video conferencing application,
supporting some of the most popular internet telephony protocols (SIP and
H.23).
Main features:
* Ease of use with a modern GUI (Graphical User Interface).
* Audio and Video free calls through the internet.
* Free Instant Messaging through the internet with Presence
support.
* Audio (and video) calls to landlines and cell phones with
support to the cheapest service providers.
* High Definition Sound (wideband) and Video Quality up to
DVD quality (high framerate, state of the art quality codec and frame size).
* Free of choice of the service provider.
* SMS to cell phones if the service provider supports it
(like the default provider).
* Standard Telephony features support like Call Hold, Call
Transfer, Call Forwarding, DTMF.
* Remote and Local Address Book support: Remote Address Book
support with authentication using the standard LDAP technology, Local Address
support in Gnome (Evolution).
* Multi platform: Windows and GNU/Linux
* Wide interoperability: Ekiga use the main deployed
stantards for telephony protocols (SIP and H.323) and has been tested with a
wide range of softphones, hardphones, PBX and service providers.
Screenshot
2. Jitsi
Jitsi, formerly known as SIP Communicator, is a free and
open source program for instant messaging and VoIP. Primarily written in Java,
Jitsi supports multiple operating systems and a wide variety of internet
telephony and chat protocols such as SIP, XMPP and YMSG. Jitsi allows audio and
video calls, instant messaging, desktop streaming, and sharing, call hold, call
recording, and encryption for calls and chats (OTR).
Jitsi has placed the service security as one of the main
necessary functions for the product development. It is characterized by the
following features:
* Encrypted password storage.
* Password protection with a master password.
* Encrypted Instant Messaging with Off-the-Record Messaging
(OTRv4).
* Chat authentication with the Socialist Millionaire
Protocol over OTR.
* Call encryption with SRTP and ZRTP for XMPP and SIP.
* Call encryption with SRTP and SDES for XMPP and SIP.
* DNSSEC support.
* TLS support and certificate-based client authentication
for SIP and XMPP.
Screenshot:
3. MicroSIP
MicroSIP is a portable, open source softphone appfor making
calls using the SIP protocol. It allowing to do high quality VoIP calls
(person-to-person or on regular telephones) via open SIP protocol. From cloud
of SIP providers you can choose best for you, register account and use it with
MicroSIP. You'll get free person-to-person calls and cheap international calls.
Main Features:
* Small footprint (>2.5MB) and RAM usage (>5MB) -
written in C and C++ with minimal possible system resources usage.
* Usability - user friendly in daily usage.
* Functionality - voice; video H.264 and H.263+; SIMPLE
messaging (RFC 3428) and presence (RFC 3903, 6665).
* Compatibility - strongly conform to SIP standards.
* Voice quality - supports best voice codecs:
speex@8,16,32kHz, iLBC@8kHz, GSM@8kHz, G.711@8kHz (PCMU and PCMA), G.722@16kHz,
G.729@8kHz, SILK@8,12,16,24kHz, Linear PCM@8,16,44kHz.
* Privacy - configurable encryption TLS / SRTP for control
and media.
* Portability - stores setting in ini file.
* Multilanguage interface - included localization files for Brazilian,
Bulgarian, Chinese, Dutch, Estonian, Finnish, French, German, Hebrew, Hungarian,
Italian, Korean, Norwegian, Polish, Russian, Spanish, Swedish, Ukrainian, etc.
Screenshot: