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.
For businesses, VoIP obviates separate voice and data pipelines, channelling both types of traffic through the IP network while giving the telephony user a range of advanced abilities.
Softphones are client devices for making and receiving voice and video calls over the IP network with the standard functions of most original telephones and usually allow integration with VoIP phones and USB phones instead of using a computer's microphone and speakers (or headset). Most softphone clients run on the open Session Initiation Protocol (SIP) supporting various codecs. Skype runs on a closed proprietary networking protocol but additional business telephone system (PBX) software can allow a SIP based telephone system to connect to the Skype network.[1] Online chat programs now also incorporate voice and video communications.
Other VoIP software applications include conferencing servers, intercom systems, virtual foreign exchange services (FXOs) and adapted telephony software which concurrently support VoIP and public switched telephone network (PSTN) like Interactive Voice Response (IVR) systems, dial in dictation, on hold and call recording servers.
Some entries below are Web-based VoIP; most are standalone Desktop applications.
Program | Operating systems | License | Costs | Protocols | Codecs | Encryption | Max conference peers | Other abilities | Latest release | ||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
AudioCodes MobilityPLUS | Windows, Android, iOS | Proprietary | ? | SIP, RTP, XMPP, STUN, ICE | G.722 wideband, G.711a, G.711u, iLBC, G.729a, SILK, GSM, VP8, H.264, Opus | TLS, SRTP | Unknown | Voice, video, IM, Group chat, content sharing, SMS and MMS over IP services, native and social network contacts integration, incoming call/IM push notifications. | 2014 | ||||||||||||
Avaya Application Server 5300 Soft Client | Windows | Proprietary | ? | SIP, RTP | Unknown | TLS, SRTP | Unknown | 2.0; 2010 | |||||||||||||
Blink | Linux, macOS, Windows | Mixed: free software versions under GNU GPLv3 + shareware versions under gplv3 with exception of including proprietary code | macOS version proprietary on App Store, free version limited to sponsored SIP provider; Windows version proprietary; Linux version open source | ICE, SIP, MSRP, RFB (VNC), XCAP | Opus, speex, G.722, GSM, iLBC, PCMU, PCMA | TLS, SRTP and ZRTP on all versions, OTR/SMP on Linux and macOS only[2] | No limit | IM, file transfer, desktop sharing, multi-party conference, wideband | Blink Qt | ||||||||||||
CSipSimple | Android | GPL | Free | SIP, ICE, STUN, TURN | Opus, AMR, G.711 (u-law/a-law), speex, G.722, GSM, iLBC, G.729 (need to buy a licensed plugin), iSAC, SILK (narrow-band/wide-band/ultra wide-band) | SRTP, SIP over TLS 1.0 and ZRTP | Unknown | SIP SIMPLE messaging, Support for IPv6, Integration with Android operating system with filters and rewriting rules | 1.0.2; November 2014 | ||||||||||||
Cisco IP Communicator[3] | Windows | Proprietary | Free (for Cisco SMB Partners only) | SCCP (Skinny), SIP, TFTP, HTTP (for XML Services) | G.722 wideband, G.711a, G.711u, iLBC, iSAC, G.729a, G.729ab | SRTP | No limit (with bridge), 2 otherwise[4] | Call Recording, Silent Monitoring, Multiple lines and directory numbers, Configurable speed dial, Calling name and number display, Call Waiting, Call Forward, Call Transfer, Three-Way Calling (conference), Call Park, Call Pickup, Redial, Hold, Barge, Callback, Extension Mobility, Message waiting indicator, iDivert, Meet Me conferencing, Group Pickup, Do Not Disturb, XML Services | 8.6.6; April 27, 2016 | ||||||||||||
CounterPath Corporation Bria | Windows, macOS, iOS, Android | Proprietary | ? | SIP, RTP, XMPP, STUN, ICE | G.722 wideband, G.711a, G.711u, iLBC, G.729a, SILK, GSM, VP8, H.264, Opus | TLS, SRTP | 6 party voice, 3 party video | Voice and video calling, SIP and XMPP messaging support, group chat, file, image and document sharing, contact integration, incoming call/IM push notifications | 5.3.4 July 23, 2018 | ||||||||||||
Discord | macOS, Android, iOS, Windows, Linux | Proprietary | Free, Premium "Nitro" Subscription for Additional Features. | RTP, UDP, WS, HTTPS | Opus | TLS | 5000 soft limit for voice calls,[5] 25 hard limit for video[6] | IM, file sharing, in-game overlay | 59746; April 24, 2020 | ||||||||||||
Ekiga | Linux, Windows, OpenSolaris | GPL | Free | SIP, H.323, STUN, Zeroconf, XMPP, RTP | H.263, H.264/MPEG-4 AVC, Theora, iLBC, Speex, SILK, GSM, ... | No | Unknown | Video, IM, LDAP, Call Forwarding, Call Transfer, Auto-answering, PC to phone, phone to PC, Multiple accounts, USP support, Message waiting indicator, SIMPLE-based presence etc. | 4.0.1 (February 21, 2013[±][7] | )||||||||||||
Empathy | Linux | GPL | Free | SIP, XMPP (Jingle), ICE (STUN-TURN), Zeroconf | Unknown | No | Unknown | IM, multi-user A/V,[8] collaborative applications | 3.12.12[9] (May 13, 2016 ) [±] | ||||||||||||
Eyeball Chat | Windows | Proprietary | Free | SIP, STUN, ICE, XMPP | Unknown | Yes | 5[10] | IM, Conferencing, Voice, Video and SIMPLE based presence | Windows 3.2; 2009 | ||||||||||||
eyeBeam | Windows | Proprietary | ? | SIP-SIMPLE | Unknown | TLS, SRTP | 6 party audio; 3 party video | Voice and Video calling; IM; Import Microsoft Outlook Contacts; USB Support; Call Recording and Conferencing | 1.5.20.1; March 2010 | ||||||||||||
FaceTime | iOS, macOS | Proprietary | Free | SIP, IETF, Signaling protocol for VoIP, STUN, TURN and ICE| IETF, technologies for traversing firewalls and NAT | H.264 Video, AAC-ELD Audio, H.263 and VP8 | RTP, SRTP IETF|standards for delivering real-time and encrypted media streams for VoIP. | 20 | Video, voice, conferencing, with additional tools available as "Services". | |||||||||||||
Google Hangouts | Linux, Windows, macOS, Android, iOS | Proprietary (using libjingle) | Free | XMPP | H.264/SVC, H.264/AVC, H.263 and VP8 | SRTP | 10 | Video, chat, screen sharing, with additional tools available as "Hangout Apps". | Google Chrome Web Store extension 2020.803.419.1 (August 12, 2020 ) [±] [11] | ||||||||||||
IBM Sametime | Linux, macOS, Windows, mobile | Proprietary | ? | SIP-SIMPLE, T.120 | H.323 | TLS | Unknown | IM, File transfer, Voice, Presence, Server stored contact list, HTTP tunneling, plugins, embedable in Lotus Notes[12] | 8.5.2; May 8, 2011 | ||||||||||||
Jami by Savoir-faire Linux | Android, FreeBSD, iOS, iPhone, Linux, Microsoft Windows, OS X[13] | GPL | Free | SIP, RTP, STUN per account, SRV, DHT, P2P | Audio: Opus, Speex, G.722, G.711, GSM, VP8, G.729, iLBC. Video: H.264, H.263, VP8, MPEG-4 | Voice encryption (SRTP with SDES or ZRTP) and signaling encryption (TLS), multiple realms authentication mechanism | No limit | Blockchain ID-management, Gnome-KDE client, address book, multiple accounts, unlimited call number, call transfer, call hold-unhold, call recording, multi-way conferencing |
| ||||||||||||
Jitsi | Linux, macOS, Windows (all java supported). Experimental Android builds are also available.[18] | Apache | Free | SIP-SIMPLE, XMPP-Jingle STUN ICE, TURN | SILK, G.722, Speex, Opus, G.711 (PCMU/PCMA), iLBC, GSM, G.729, H.264, H.263, VP8 | ZRTP, SRTP, OTR, TLS | Unknown | Text messaging, audio-video telephony, IPv6 (often broken,[19] P2P not supported[20]), call recording, 64-bit | 2.10 (build.5550) (February 5, 2017[±] | )||||||||||||
KPhone | Linux (KDE) | GPL | Free | SIP, STUN, NAPTR-SRV | Unknown | SRTP | Unknown | Video, voice, IM, external Sessions, IPv6 support for UDP | 1.2 (November 2008) | ||||||||||||
Librestream Onsight Connect | Windows, Android, iOS | Proprietary | ? | SIP, RTP, STUN | G.711, H.264, MPEG, and others | TLS, SRTP | Unknown | Voice, video, conferencing, image sharing, incoming call/IM push notifications. | February 27, 2018 | ||||||||||||
Linphone | Linux, Windows, macOS, Android, iPhone, BlackBerry | GPL v.3 | Free | SIP | Speex, Opus, G711, GSM, G.722, VP8 (WebM), H263, MPEG4, Theora and H264 (plugin) | TLS, SRTP, ZRTP | Unknown | Video, IM, STUN, IPv6 (disables IPv4 support when enabled, P2P, Secure Encrypion, User own Encryption via Provided API [https://gitlab.linphone.org/BC/public/linphone-desktop) | 4.1.1; April 30, 2020http://www.linphone.org/snapshots | , provides daily snapshots via||||||||||||
Messages | macOS | Proprietary | Free, only macOS and iOS | SIP AIM ICQ XMPP | H263, H264 | Unknown | Unknown | Integrated, PBX independent | 7.0; July 25, 2012 | ||||||||||||
MicroSIP | Windows | GPL | Free | SIP, STUN, ICE, SIMPLE | Speex, iLBC, GSM, G.711, G.722, G.729, SILK, Linear PCM | TLS, SRTP | Unknown | Video, voice, IM and Presence | 3.20.3 (2 November 2020[±][21] | )||||||||||||
Mirial Softphone (Mirial s.u.r.l.) | Windows 2000-XP-2003-Vista-7 (including 64-bit versions), macOS (x86) | Proprietary | not free | SIP, RTSP | H.323 | DTLS-SRTP | Unknown | H.264 Full-HD 1080p video rx/tx, Two independent lines supporting Call Control and 3-Party videoconference in Continuous Presence, G.722.1/C wideband audio, Call recording/export, DV/HDMI/Component capture, Presentation (H.239, RFC-4796), Encryption, Far End Camera Control, GPU accel (D3D and OpenGL) | 7.0.24; May 26, 2010 | , discontinued||||||||||||
Mumble | Linux, macOS, iOS, Windows, Android | New BSD license | Free | ICE | CELT, Speex, Opus | TLS and OCB-AES128 | No limit (limited only by server bandwidth and memory) | Chat with (limited) embedded HTML, Automatic Gain Control, very low latency, Access Control Lists for user management, Customizable In-Game Overlay for OpenGL and DirectX, Directional Audio, Plugin Support, Nested Channels, Echo cancellation for headset free use, Global Public Server List, Logitech G15 support, Push-To-Talk and Voice-Activation | 1.3.0; September 7, 2019 | ||||||||||||
Nymgo | Windows, Android, iOS | Proprietary | Free | SIP, RTP and RTCP | Unknown | Yes | No limit | Address Book integration, Call recording/export, Mute, On Hold, Caller ID definition | 4.2.9; March 2013 | ||||||||||||
oovoo | macOS, iOS, Windows, Android | Proprietary | Free | SIP, RTP and RTCP | Unknown | Yes | 12 | Address Book integration, Call recording/export, Mute, On Hold, Caller ID definition | 4.2.9; March 2013 | ||||||||||||
Phoner | Windows | Proprietary | Free | SIP, TAPI, CAPI | G.711a, G.711u, G.722, G.726, G.729, GSM, iLBC, speex, Opus | TLS, SRTP, ZRTP | 8 | Conferencing, call redirection, call recording | 3.22 (25 October 2019[±][22] | )||||||||||||
PhonerLite | Windows | Proprietary | Free | SIP | G.711a, G.711u, G.722, G.726, G.729, GSM, iLBC, speex, Opus | TLS, SRTP, ZRTP | 8 | Conferencing, call redirection, call recording | 2.88 (16 February 2021[±][23] | )||||||||||||
QuteCom | Linux, macOS, Windows XP-2000 | GPL | Free | SIP | G.711, G.729, iLBC, AMR-NB, G.722, Speex, AMR-WB (G.722.2), H.263, H.263+, H.264, Dirac[24] | SRTP, but key exchange via Everbee key Exchange which is not a Standard | Unknown | Video, IM (MSN, AIM, ICQ, Yahoo!, XMPP, Google Talk), voicemail, wengo to phone, conferencing. | 2.2.1 (22 June 2011[25]) [±] | ||||||||||||
Roger Wilco GameSpy | Windows | Proprietary | ? | Proprietary | ? | ? | Unknown | ? | 2001 | ||||||||||||
Signal | Linux, macOS, Windows, Android, iPhone | GPLv3 clients and AGPLv3 server | Free | RingRTC (WebRTC over Signal protocol[26]) | Opus[26] | ? | Unknown | Signal also allows users to send text messages, files, voice notes, pictures, GIFs, and video messages over a Wi-Fi or data connection to other Signal users on iOS, Android and a desktop app. The app also supports group messaging, read receipts and typing indicators, both of which can be disabled. |
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Skype | Linux(with limited functionality),[30] macOS, Windows 2000-XP-Vista-7-Mobile (unsupported), BREW, Windows Phone, Android, iPhone, PSP | Proprietary | Free | Proprietary P2P protocol [a] | SILK | TLS | 25 starting with version 3.6.0.216. 10 with 2.x | Conferencing, video, file transfer, voicemail, Skype to phone, phone to Skype, additional P2P extensions (games, whiteboard, etc...); depending on platform. |
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TeamSpeak | Linux, Windows, macOS, FreeBSD, Android, iOS | Proprietary | Free | Unknown | CELT, Speex (both until server version 3.5.0), Opus[35] | Yes | 32 unlicensed, 512 with Non-Profit License (available until September 2018), up to 1024 (Gamer License), 2000 | Simultaneous server conferencing with tabs, 3D sound effects, scalable permissions system, firewall friendly file transfers, in-game overlay for DirectX & OpenGL games, global public server list, plugin system | 3.5.5; November 4, 2020 | ||||||||||||
TeamTalk | Linux, Windows, macOS, Android, iOS, Raspbian | Proprietary | Free | Proprietary | Opus, Speex, WebM | No | 1000 | Video, file sharing, desktop sharing, stream media files (MP3, AVI) | 5.3.3; November 2018 | ||||||||||||
TeamViewer | Linux, Windows, macOS, iOS, Android[36] | Proprietary | Free (personal use only) | Unknown | Unknown | AES256 | Unknown | Unknown |
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Telephone | macOS 10.10.2 | BSD | Free | SIP, STUN, ICE | Unknown | No | Unknown | Address Book integration | 1.1.4; March 6, 2012 | ||||||||||||
Toktumi Unlimited, Line2 Pro | Windows XP-Vista-7, macOS, iOS, Android | Proprietary | Free | Proprietary with SIP core | Unknown | Unknown | 20 | Conferencing, voicemail, caller ID, call-waiting, address book integration; auto-attendant, call-forwarding | Windows; August 2010 | ; macOS; October 2010||||||||||||
Tox | Linux, macOS, Windows, Android, FreeBSD | GPL | Free | Tox, VP8 | Opus, | NaCl | Unknown | Voice, video, instant messaging, file transfers | Unknown | ||||||||||||
Tru App | Windows 2000-XP-Vista-7, macOS, Linux iOS, Android, Symbian, BlackBerry OS, |
Proprietary | Free | SIP, XMPP | Unknown | Unknown | Unknown | Chat, file transfer, voicemail, inbound numbers, integration with GTalk, Microsoft Live, Skype | |||||||||||||
Tuenti | Android, iPhone, Windows Phone | Proprietary | Free | WebRTC, SIP, XMPP | iLBC, Opus | Yes | Unknown | Voice, video, Instant messaging, group chat, photo and video sharing, SMS and MMS, native and social network contacts integration, incoming call/IM push notifications. | |||||||||||||
Twinkle | Linux | GPL | Free | SIP | G.711 A-law μ-law, G.726, GSM, iLBC, Speex narrow wide ultrawide | SRTP, ZRTP | 3 | Conferencing, chat, file transfer, Firefox integration, call redirection, voicemail, support of VoIP-to-Phone services | 1.10.2 (February 14, 2019[±] | )||||||||||||
Ventrilo | macOS, Windows, iOS, Android | Proprietary | Free | Unknown | Unknown | No | 8 | Conferencing, chat, text-to-speech | 3.0.8 | ||||||||||||
Viber | Linux,[b] macOS,[b] Windows,[b] Android, Bada, BlackBerry OS, iOS, Series 40, Symbian, Windows Phone | Proprietary | ? | Unknown | Unknown | Yes[45] | Unknown | Varies by platform: Text, picture and video messaging on all, voice calling only on iPhone, Android and Microsoft's Windows Phone |
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Vonage | Linux, macOS, Windows, Android, iOS | Proprietary | not free | SIP, STUN, ICE, TURN | Audio: Opus, G.711
Video: VP8 |
SRTP | 50 | VoIP, video, instant messaging, presence (SIP SIMPLE), PSTN (inbound and outbound), call waiting, call hold, call forwarding, voicemail, message-waiting indication, 3-way conferencing, contacts integration, receptionist console, video, group chat, content sharing, SMS over IP services, native and social network contacts integration, incoming call/IM push notifications, fax, file sharing, screen sharing (desktop only), number programmability. | |||||||||||||
Wire | Linux, Windows, macOS, iOS, Android, Web | GPLv3 | not free | ? | Audio: Opus
Video: VP8 |
DTLS, SRTP[52] | 10[53] | End-to-end encryption by default for everything, instant messaging, video call, video group call, file sharing, GIF sharing, push to talk, edit message, delete message (on both side), timed messages, doodling, identity verification, screen sharing (desktop only) | ? | ||||||||||||
X-Lite | macOS, Windows | Proprietary | Free | SIP, STUN, ICE, TURN | H.263, H.263+, G.711, iLBC, Speex | No | 3 | VoIP over WiFi, 3G, 4G, video, instant messaging, presence (SIP SIMPLE), call waiting, call hold, call forwarding, voice mail, message waiting indication, 3 way conferencing, contacts integration, background noise reduction (BNR), automatic gain control (AGC) | 5.3.3 July 10, 2018 | ||||||||||||
Yahoo! Messenger | Classic Mac OS (8, 9), macOS, Windows, (Linux, FreeBSD version VoIP incapable) | Proprietary | Free | SIP (using TLS) and RTP (media) | Unknown | Unknown | Unknown | Video, file transfer, PC to phone, phone to PC | Windows: 11.5.0.228; May 31, 2012 Mac: 3.0.1; July 20, 2011 Linux: 1.0.6; September 2003 SunOS 5.7: 0.99.17-1; September 2003 Solaris 8: 1.0.4; September 2003 FreeBSD 4-5: 1.0.4; September 2003 iOS: 2.2.6; July 12, 2012 | ||||||||||||
Yate Client | Linux, macOS, Windows | GPL | Free | SIP, IAX, XMPP, H.323 | G.711a, G.711u, GSM 06.10, iLBC, Speex, G.723, G.726, G.728, G.729 | SRTP, maybe ZRTP? | Unknown | 6.0.0; September 2017 | |||||||||||||
Zfone | Linux, macOS, Windows | Proprietary (with viewable source) | Includes time bomb provision | SIP, RTP | Unknown | SRTP, ZRTP | Unknown | Beta 2008-09-04 (Linux 0.9.224), (macOS 0.9.246), (Windows 0.9.206) |
For mobile VoIP clients:
Program | Operating systems | License | Open source | Protocols | Codecs | Encryption | Other abilities | Latest release | ||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Acrobits Softphone | Android v2.2+, iOS v7.0+ | Proprietary | No | SIP | G.711, G.722, iLBC, GSM, G.729 | TLS, SRTP, ZRTP | VOIP over Wi-Fi or 3G iOS only: push notifications, video, number rewriting, address book matching, sms for betamax providers and pennytel | Acrobits Softphone: 3.20 (Android), 5.2 (iOS) | ||||||
CounterPath Corporation Bria | Android v4.4+, iOS v10+ | Proprietary | No | SIP | G.722 wideband, G.711a, G.711u, iLBC, G.729a, SILK, GSM, VP8, H.264, Opus | TLS, SRTP, ZRTP | Voice and video calling, SIP and XMPP messaging support, group chat, file, image and document sharing, contact integration, incoming call/IM push notifications. | 5.3.4 July 23, 2018 | ||||||
CSipSimple | Android | GPL | Yes | SIP | Opus, AMR-WB, G.722, iSAC, iLBC, Speex, Silk, Codec2, G.726, G711 (PCMA & PCMU), AMR, GSM | SRTP, SIP over TLS 1.0 and ZRTP | ? | 1.02.02 | ||||||
Google Duo | iOS, Android | Proprietary, freeware | No | WebRTC | ? | ? | One-to-one voice and video calling. |
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iCall Mobile | iOS v4.3+ | Proprietary, freeware | No | SIP AIM ICQ XMPP, Facebook, Yahoo! Messenger, Windows Live | Speex, CELT, WebM | TLS, ZRTP | VoIP over Wi-Fi or 3G, SMS, voicemail | 2.0.1; April 2012 | ||||||
Jajah Mobile Web | Symbian, Windows Mobile (version unknown) | Proprietary | No | ? | ? | ? | web based service, Call back, no download[54] | ? | ||||||
JusTex by Juphoon | Android, iOS v5.1+ | Proprietary | No | SIP | PCMA, PCMU, G.722, iLBC, iSAC, Opus, H.264, VP8, H.263 | TLS, TCP, UDP, SRTP | JusTex Softphone over Wi-Fi or 3G, HD voice and video call, Multiparty call, conference. | 3.0.1 (iOS); July 13, 2014 | ; 3.0 (Android); July 9, 2014||||||
Line | Android, iOS | Proprietary | No | ? | ? | ? | ? | |||||||
Line2 | Android, iOS | Proprietary, freeware | No | Proprietary with SIP core | ? | ? | Tri-mode calling (cellular, 3G/4G data, Wi-Fi), SMS over IP, visual voicemail, 20-person conference calls, auto-attendant, call-forwarding | 1.0.4 Android, 3.2.1 iOS | ||||||
Media5-fone | iOS, Android | Proprietary | No | SIP | PCMA, PCMU, G.722*, iLBC, iSAC*, G.729* | TLS*, SRTP* | Wi-Fi and 3G/4G data, second call*, conference calls*, HD Voice, Bluetooth* (* Additional fees) | ? | ||||||
Signal by the Signal Foundation | iOS, Android | GPLv3 | Yes | WebRTC[55] | Opus[55] | TLS, Signal Protocol[55] | End-to-end encryption by default for everything. CallKit and location privacy,[56] one-to-one and group messaging, video calling,[56] image/video sharing, timed messages, identity verification, screenshot blocking. Android only: SMS/MMS messaging, doodling,[57] GIF sharing.[58] |
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Sipdroid | Android | GPL | Yes | SIP | ? | ? | Uses Wi-Fi, 3G or EDGE | 2.7 | ||||||
Tango by TangoME Inc. | iOS, Android, Microsoft Windows, macOS, Windows Phone | Proprietary, freeware | ? | ? | ? | ? | VoIP, Wi-Fi out & in, SMS over IP, call-through & call-back, instant messaging, videoconferencing | ? | ||||||
Truphone | Nokia-Symbian, iOS, Android, BlackBerry | Proprietary, freeware | No | SIP | ? | ? | VoIP, Wi-Fi out & in, SMS over IP, call-through & call-back, connection management, provisioning | Symbian 4.0, iOS 1.11.1 | ||||||
Vopium | Symbian, Java ME, Android, BlackBerry RIM, iOS, Windows Mobile 2003 SE and higher | Proprietary, freeware | No | SIP, MSN, Skype, Yahoo, AOL, ICQ, Google Talk, Facebook & Twitter | GSM | ? | Wi-Fi VoIP, GSM call-through, SMS over IP, least cost routing, synchronising-backup mobile contacts and calendar | 2.0 | ||||||
Android, BlackBerry, iOS, Symbian, Windows Phone |
Proprietary, freeware | No | ? | ? | ECDH, SRTP[62] | VoIP and instant messaging over Wi-Fi or a data connection. |
| |||||||
Windows Mobile 6 | Windows Mobile 6 Professional/Standard | Proprietary | No | SIP to publicly and non-publicly routable servers | ? | ? | Wi-Fi Mobile VoIP | 6.1 | ||||||
X-PRO for Pocket PC | Windows Mobile 2003 (earlier versions support Windows PocketPC 2002) | Proprietary, discontinued in April 2007[66] | No | SIP | ? | ? | Supported devices: AudioVox Maestro, Compaq/HP iPAQ: 365x, 37xx, 385x, 395x, hx4700, Dell Axim X51, X51v, Toshiba e550, e570. iPAQ 545x and Toshiba e7xx are not supported.[67] | 2.2 | ||||||
Yuilop | Android, iOS | Proprietary, freeware | No | XMPP, RTP | iLBC | TLS | VoIP over 3G-4G-LTE and Wi-fi, SMS, group chat, photo sharing, Location sharing, virtual phone numbers | iOS 2.4 (November 26, 2014[68]) [±] Android 2.0.2 (February 12, 2014[±] | ||||||
Linkus | Android V4.4+, iOS v10.0+ | Proprietary, freeware | No | SIP | iLBC | TLS, SRTP | HD VoIP Call, Instant Messaging, Conferencing, SRTP Secure Media, Presence information | iOS 2.7.9
Android 2.7.12 |
Program | Operating systems | License | Protocols, based on, compatible with | Encryption | Other abilities | Key and target markets | Latest release |
---|---|---|---|---|---|---|---|
Tapioca | Linux | GPL | Telepathy (software) | No | 0.3.9; June 12, 2006 | ||
Telepathy, Farstream | Linux, macOS, Windows | LGPL | SIP, XMPP (Jingle), ICE (STUN/TURN), UPnP | No | Multi-user A/V conferencing, IM, collaborative applications | Mobile devices (Maemo, Meego), Linux desktop or embedded | spec 0.27.2; September 24, 2013 |
OPAL | Windows, Linux (including embedded variants), macOS | MPL | SIP, H.323, IAX2, CAPI, VXML | Unknown | Multi-user A/V conferencing, IM, IVR | Softphones, softswitches, telephony application servers | 3.14.3; October 10, 2014 |
GNU oSIP | Linux, Windows, macOS, Android, iPhone, BlackBerry | LGPL | SIP, SDP | Unknown | Multi-user A/V conferencing, IM, IVR | Softphones, embedded and mobile devices, telephony application servers | 4.1.0; December 18, 2013 |
Program | Operating systems | License | Protocols, based on, compatible with | Encryption | Other abilities | Key and target markets | Latest release |
---|---|---|---|---|---|---|---|
3CX Phone System | Windows, Linux | Proprietary | SIP | TLS, SRTP | Voice and video IP telephony and conferencing, voice mail and instant messaging | < 50,000 users | 16.2; July 5, 2019 |
AS5300 | Linux, Windows Server 2003 | Proprietary | SIP, UNIStim, MLPP | SSL, TLS,
SRTP, SDESC |
Voice and Video IP telephony, Voice and Video conferencing, voice mail and instant messaging | 1,000 - 25,000 users | 1.0; January 2008 |
AskoziaPBX | no additional OS required (Linux based) | GPL, Open core | SIP, H.323, IAX, SCCP | No | ISDN, analog, Voicemail, Conferencing, MOH, ACD, IVR, Call forwarding, Call recording | SMEs up to 50 users | 2.2.2; December 2012 |
Asterisk PBX | Linux, BSD, macOS, Solaris | GPL, optional: Proprietary[70] | SIP, H.323, IAX, MGCP, VOFR, XMPP, Google Talk, TDM | TLS, SRTP | VoIP Gateway, voicemail, basic accounting (can be expanded by interface with ODBC-compliant database), billing, conferencing, hot-desking, IVR trees with conditional logic, call queuing, automated call distribution | Enthusiasts, developers, enterprise users (capacity dependent on server design, scalable across multiple servers) | 18.2.1 (18 February 2021[71]) 17.9.2 (18 February 2021[72])
|
Brekeke SIP Server | Linux, Windows | Proprietary | SIP | TLS, SRTP | SIP Registrar, SIP Proxy | SIP Service Providers, VoIP service providers, Healthcare, Security | 3.9.1.3; December 21, 2018 |
Brekeke PBX | Linux, Windows | Proprietary | SIP | TLS, SRTP | Voice and Video IP telephony, Voice and Video conferencing, and voice mail | Hosted service providers, Mid-large enterprise | 3.9.1.4; December 27, 2018 |
CallMax Softswitch | Linux | Proprietary | SIP, H.323 | SSL, TLS, HTTPS | Integrated billing, IP PBX Platform, Calling card platform, Callshop module, Customer Web Portal, Retail SMS Platform. | SIP Service Providers, Residential & Business VoIP providers, Corporate Clients, Other Class 5 softswitch users | 3.6; October 2015 |
CommuniGate Pro | Linux, BSD, macOS, Windows, Solaris, HPUX, AIX | Proprietary | SIP, XIMSS Protocol, XMPP, WebRTC | SSL, TLS, SRTP | SIP Registrar/Proxy, Authentication, Diameter, RADIUS, ENUM, many others | Carriers, enterprises, MNOs, ISPs, SaaS providers | 6.1.11; June 2016 |
Dial-Gate Softswitch PBX | Linux, Windows | Proprietary | SIP | TLS, SRTP | Billing server, real-time account and line monitoring, web-based user interface | Softswitch users, service providers | 4.3; June 2014 |
Dial-Office IP-PBX | Linux, Windows | Proprietary | SIP | TLS, SRTP | Unified Communications, Conferencing, remote worker support and voice mail | Small businesses, Mid-large enterprises | 4.1; December 2013 |
Elastix | Linux | GPL | SIP, IAX, H323, XMPP | TLS, SRTP | Unified communication server that also supports chat, mail and fax. | Capacity dependent on server design, scalable across multiple servers | 2.5.0 (stable), 3.0.0 (stable), 4.0.0 (stable); February 10, 2016 |
FreeSWITCH | Linux, BSD, macOS, Solaris, Windows | Mozilla Public License | SIP, NAT-PMP, STUN, SIMPLE, XMPP, Google Talk (Jingle), IAX, H.323, MRCP, RSS, Skype | TLS, SRTP, ZRTP | Recording, Voicemail, Conferencing, RADIUS, ENUM, IM Proxy, Streaming, Media gateway, Soft-PBX, IVR (modular) | Large soft-switch users, home PBX users, softphone users | 1.10.4 (August 5, 2020[75]) [±] |
FreePBX | Linux, BSD, Solaris | GPL | SIP, IAX, H323, XMPP | TLS, SRTP | Complete PABX Service, based on Asterisk and PHP 5.6; provides a full replacement for a legacy non-VoIP phone system; under current and active development | Scales from Raspberry PI (3 users) to multiple parallel clusters (10K+ simultaneous calls) | 14.0; August 2017 |
GNU Gatekeeper | Linux, FreeBSD, macOS, Windows XP-2000-Vista-7 | GPL | H.323 | H.235 | H.460.18 firewall traversal, routing, accounting | video conferencing, VoIP carriers large and small | 3.7; August 15, 2014 |
HERO Hosted PBX | Linux, Windows | Proprietary | SIP | TLS, SRTP | Unified Communications, billing server, cloud-based management and web interface | Mid-large enterprises, VoIP carriers and service providers, telecom operators | 4.3; December 2013 |
Kerio Operator | Linux, VM | Proprietary | SIP | SSL, TLS, SRTP | integrated firewall, Auto attendant, Call queues, Conference calling, Call forwarding, pickup, parking, recording, Click to Call, Video calling, Fax support, Paging, Salesforce.com and CRM integration, Voicemail to email, complementary desktop Softphone app | SME | 2.5.2; November 15, 2016 |
MediaCore SBC | Linux | Proprietary | H.323, SIP, SMPP, HTTP | SSL, TLS, HTTPS | Dynamic routing mechanism including LCR, Jurisdictional routing support, origin based routing, integrated billing, SIP-H.323 protocol converter, Transcoding - codec converter module, Guardian - revenue assurance module, SBC functionality, full and media proxy, Wholesale messaging and SMS hubbing | Transit VoIP services providers, VoIP wholesale carriers, VoIP termination providers, Wholesale messaging providers | 4.8; February 2021 |
Murmur | Linux, BSD, macOS, Windows | BSD, GPL | CELT, Speex, Opus | TLS | Chat with (limited) embedded HTML, ACLs for user management, Customizable In-Game Overlay, Directional Audio, Plugin Support, Nested Channels | Individuals to Small and medium enterprise (25-5000 users) | 1.2.17; September 24, 2016 |
Mysipswitch | Linux | BSD | SIP, Ajax | SSL | SIP proxy server which allows the use of multiple SIP accounts with a single SIP login | Individuals | August 2007 |
Objectworld UC Server | Windows XP-2003-2008 | Proprietary | SIP | No | IP PBX, personal assistants, IVR, automated phone provisioning, fax server, unified messaging, Outlook, Exchange and Lotus Domino-Notes integration, conferencing, outbound dialing | Small and medium enterprise (25-2000 users) | 4.4.2; May 2009 |
Kamailio, OpenSIPS (formerly named OpenSER) | Linux, BSD, Solaris | GPL | SIP, XMPP | TLS, SRTP | SIP registrar-proxy, authentication, Diameter, RADIUS, ENUM, least-cost-routing, many others | SIP Service Providers | 5.2.8; October 2020 |
Pbxnsip | Linux, BSD, macOS, Windows | Proprietary | SIP | SRTP | IP PBX, presence indication, IVR, automated phone provisioning, fax server, unified messaging, Outlook, Exchange integration, conferencing, outbound dialing | Small and medium enterprise (25-256 users) | 3.3.1.3177; April 2009 |
SIP Express Router (SER) | Linux, BSD, Solaris | GPL | SIP | No | SIP Registrar/Proxy, Authentication, Diameter, RADIUS, ENUM, many others | SIP Service Providers | 2.0.0 Ottendorf |
sipXecs IP PBX | Linux | AGPL | Native SIP call control, XMPP | TLS, SRTP | Full redundancy (HA), instant messaging, voicemail, user portal, admin GUI, plug & play management including phones and gateways, fully featured | Enterprises between 10 and 10,000 users, multi-site | 14.04.2; July 2014 |
vzRoom | Windows | Proprietary | SIP | SSL, TLS, AES | Instant messaging-chat, VoIP, video, sharing (desktop, video, file), whiteboard, scheduler, recording | Individual to small and medium enterprise (2-1,000 users) | 0.8.8.735; November 2010 |
Yate | BSD, Linux, macOS, Windows | GPL | SIP, IAX, H.323, ISDN, XMPP (Jabber), Jingle (Google Talk), MGCP, SS7 over IP, Cisco SLT (Signalling Link Transport) (SS7 MTP2 backhaul over IP), SCTP, SCCP, TCAP, MAP CAMEL | SSL, TLS, SRTP | Voice, video, file transfer, data, H323 to SIP signalling proxy, instant messaging, IVR, PC2Phone and Phone2PC gateway, SCCP — GTT routing between networks, Secure Unified Communications, SIP registrar-proxy, SIP SBC (session border controller), USSD, voicemail, VoIP, VoIP to PSTN gateway, conference server (max 200 voice channels per conference), call centre server, prepaid and postpaid cards | Deployed on home servers and large networks with millions of users | 5.5; May 2015 |
![]() | This section needs expansion. You can help by adding to it. (July 2016) |
The following table is an overview of those VoIP clients which (can) provide end-to-end encryption.
Client name | Development status | Open source client | End-to-end authentication[a] | Encryption protocols | Forward secrecy | Multiple encryption | Encrypted group calling | Proxy, Tor | |||
---|---|---|---|---|---|---|---|---|---|---|---|
ZRTP | ECDH | DTLS | SRTP | ||||||||
FaceTime | Active | No[76] | No[76] | ? | ? | ? | ? | Yes[76] | ? | No | No |
Google Duo | Active | No | No | ? | ? | ? | ? | ? | ? | No | No |
Jitsi[b] | Active | Yes | Yes[76] | Yes | No | Yes | Yes | Yes[76] | Yes | Yes | ? |
Line[77][78] | Active | No | ? | ? | ? | ? | ? | ? | ? | No[77] | No |
Linphone[b] | Active | Yes | Yes | Yes | ? | Yes | Yes | Yes | Yes | ? | No |
PGPfone | Abandonware | Viewable source[79] | Yes | ? | ? | ? | ? | ? | ? | ? | ? |
Signal | Active | Yes | Yes[76] | No | Yes | No | Yes | Yes[76] | Yes | No | Depends[80] |
Silent Phone | Active | Viewable source[81] | Yes[76] | Yes | ? | ? | Yes | Yes[76] | Yes | Yes | No |
Skype (opt-in per conversation, one pair of devices per conversation)[82] |
Active | No | Yes[83] | No | No | No | Yes[84] | ? | ? | No | No |
Telegram | Active | Yes | Yes[85] | No | No | No | No | Yes | ? | No | No |
Threema | Active | Partially[c][86] | Yes[87] | No | Yes[87] | Yes[87] | Yes[87] | Partially[d][87] | Yes | No | No |
Viber[45] | Active | No | ? | ? | ? | ? | ? | ? | ? | ? | No |
Active | Partially[c][88] | Yes[88] | No | Yes[88] | No | Yes[88] | Yes[88] | Yes[88] | No | No | |
Wire | Active | Yes | Yes[89] | No | ? | Yes[52] | Yes[52] | Yes[90] | Yes | Yes | No |
Zfone | Abandonware | Viewable source[91] | Yes | Yes | Optional[92] | ? | Yes[93] | Yes | Yes | ? | ? |
The following table is an overview of those VoIP clients which (normally) provide client-to-server encryption.
Client name | Encryption protocols |
---|---|
Google Hangouts[76] | SRTP[94] |
Skype[76] | A custom protocol |
If you don’t have Viber on your phone and try to install the service on your PC, the app will redirect you to its website and ask you to install Viber on your phone first.
Note: Private conversations can only be accessed on one device at a time.
Users can verify the security of their conversations by checking the key setup between two users.
Caller encrypts the SRTP using the generated encryption key, which can only be decrypted by the callee. After the call is setup, the media packets are encrypted using the SRTP keys.
New encryption keys are used for each message, so a compromised key has minimal impact.