Voice over Internet Protocol (VoIP),also called IP telephony,is a method and group of technologies for the delivery of voice communications and multimedia sessions over Internet Protocol (IP) networks,such as the Internet. The terms Internet telephony,broadband telephony,and broadband phone service specifically refer to the provisioning of communications services over the Internet,rather than via the public switched telephone network (PSTN),also known as plain old telephone service (POTS).
HCL Sametime Premium is a client–server application and middleware platform that provides real-time,unified communications and collaboration for enterprises. Those capabilities include presence information,enterprise instant messaging,web conferencing,community collaboration,and telephony capabilities and integration. Currently it is developed and sold by HCL Software,a division of Indian company HCL Technologies,until 2019 by the Lotus Software division of IBM.
The landscape for instant messaging involves cross-platform instant messaging clients that can handle one or multiple protocols. Clients that use the same protocol can typically federate and talk to one another. The following table compares general and technical information for cross-platform instant messaging clients in active development,each of which have their own article that provide further information.
Skype for Business Server is real-time communications server software that provides the infrastructure for enterprise instant messaging,presence,VoIP,ad hoc and structured conferences and PSTN connectivity through a third-party gateway or SIP trunk. These features are available within an organization,between organizations and with external users on the public internet or standard phones.
A VoIP phone or IP phone uses voice over IP technologies for placing and transmitting telephone calls over an IP network,such as the Internet. This is in contrast to a standard phone which uses the traditional public switched telephone network (PSTN).
Gizmo5 was a voice over IP communications network and a proprietary freeware soft phone for that network. On November 12,2009,Google announced that it had acquired Gizmo5. On March 4,2011,Google announced that the service would be discontinued as of April 3,2011.
QuteCom was a free-software SIP-compliant VoIP client developed by the QuteCom community under the GPL-2.0-or-later license. It allows users to speak to other users of SIP-compliant VoIP software at no cost. It also allows users to call landlines and cell phones,send SMS and make video calls. None of these functions are tied to a particular provider,allowing users to choose among any SIP provider.
ZRTP is a cryptographic key-agreement protocol to negotiate the keys for encryption between two end points in a Voice over IP (VoIP) phone telephony call based on the Real-time Transport Protocol. It uses Diffie–Hellman key exchange and the Secure Real-time Transport Protocol (SRTP) for encryption. ZRTP was developed by Phil Zimmermann,with help from Bryce Wilcox-O'Hearn,Colin Plumb,Jon Callas and Alan Johnston and was submitted to the Internet Engineering Task Force (IETF) by Zimmermann,Callas and Johnston on March 5,2006 and published on April 11,2011 as RFC 6189.
This is a comparison of voice over IP (VoIP) software used to conduct telephone-like voice conversations across Internet Protocol (IP) based networks. For residential markets,voice over IP phone service is often cheaper than traditional public switched telephone network (PSTN) service and can remove geographic restrictions to telephone numbers,e.g.,have a PSTN phone number in a New York area code ring in Tokyo.
FreeSWITCH is free and open-source server software for real-time communication applications,including WebRTC,video,and voice over Internet Protocol (VoIP). It runs on Linux,Windows,macOS,and FreeBSD. FreeSWITCH is used to build private branch exchange (PBX) telecommunication systems,IVR services,videoconferencing with chat and screen sharing,wholesale least-cost routing,Session Border Controller (SBC) and embedded communication appliances. It has support for encryption,ZRTP,DTLS,and Session Initiation Protocol (SIP). It is implemented as a core library,libfreeswitch,which can be embedded into other projects. It is distributed under the Mozilla Public License (MPL),a free software license.
Jitsi is a collection of free and open-source multiplatform voice (VoIP),video conferencing and instant messaging applications for the web platform,Windows,Linux,macOS,iOS and Android. The Jitsi project began with the Jitsi Desktop. With the growth of WebRTC,the project team focus shifted to the Jitsi Videobridge for allowing web-based multi-party video calling. Later the team added Jitsi Meet,a full video conferencing application that includes web,Android,and iOS clients. Jitsi also operates meet.jit.si,a version of Jitsi Meet hosted by Jitsi for free community use. Other projects include:Jigasi,lib-jitsi-meet,Jidesha,and Jitsi.
Empathy is an instant messaging (IM) and voice over IP (VoIP) client which supports text,voice,video,file transfers,and inter-application communication over various IM communication protocols.
Jami is a SIP-compatible distributed peer-to-peer softphone and SIP-based instant messenger for Linux,Microsoft Windows,OS X,iOS,and Android. Jami was developed and maintained by the Canadian company Savoir-faire Linux,and with the help of a global community of users and contributors,Jami positions itself as a potential free Skype replacement.
A softphone is a software program for making telephone calls over the Internet using a general purpose computer rather than dedicated hardware. The softphone can be installed on a piece of equipment such as a desktop,mobile device,or other computer and allows the user to place and receive calls without requiring an actual telephone set. Often,a softphone is designed to behave like a traditional telephone,sometimes appearing as an image of a handset,with a display panel and buttons with which the user can interact. A softphone is usually used with a headset connected to the sound card of the PC or with a USB phone.
Juphoon System Software is an international company which provides IP multimedia subsystem (IMS) solutions and services. The core team was established in Shenzhen,China in 2004,and it was officially established in Ningbo,China in 2005. Juphoon System Software has done long-term research in the field of IMS applications and voice over IP (VoIP) products. They are trying to introduce the high-quality commercial Session Initiation Protocol (SIP) Stack and other protocols to international communication enterprises.
CSipSimple is a Voice over Internet Protocol (VoIP) application for Google Android operating system using the Session Initiation Protocol (SIP). It is open source and free software released under the GPL-3.0-or-later license.
Acrobits is a privately owned software development company creating VoIP Clients for mobile platforms,based in Prague,Czech Republic.
Voiceserve Inc. is a Delaware,USA telecommunications and softswitch company headquartered in Middlesex,United Kingdom and incorporated December 9,2005. The company offers VoIP,mobility,and IP-PBX software with management,administration,billing,mobility,hosted IP-PBX,and softphone functionality found among its services,VoipSwitch,Call-to-PBX,and Vippie.
Web Call Server is unified intermedia server software developed by Flashphoner. It is a server-side platform,implemented in Java,dedicated for streaming video over wide range of communication protocols,including:
