Free Sip Servers
Free Sip Server For Windows
Free Sip Server Software

Zoiper, the free softphone to make VoIP calls through your PBX or favorite SIP provider. Available for iPhone, Android, Windows Phone 8, Windows, Mac and Linux. The freedom of choice doesn’t end there, with 3CX you can choose to deploy on-premise on Windows or Linux, in your private cloud account or opt for 3CX to host your PBX for you. Whatever your preference, you are guaranteed a hassle-free PBX that requires minimum management. Get 3CX free for one year and future proof your business today!

This list of SIP software documents notable software applications which use Session Initiation Protocol (SIP) as a voice over IP (VoIP) protocol.

Sofia is a SIP stack used by FreeSWITCH. When you see 'sofia' anywhere in your configuration, think 'This is SIP stuff.' It takes a while to master it all, so please be patient with yourself. SIP is a crazy protocol and it will make you crazy too if you aren't careful. Read on for information on setting up SIP/Sofia in your FreeSWITCH.
SIP-T31P Entry-level IP Phone with 2 Lines & HD voice As a very fashionable and friendly entry-level IP phone, Yealink SIP-T31P has an extra-large 132x64-pixel graphical LCD with backlight that brings clear visual experience for users. The T31P offers support for two VoIP accounts and includes local 5-way conferencing to maximize productivity.
You can create your own sip address, for example 'sip:john@sip.linphone.org' using the form below, and your friends can call you using this SIP address. Technically, this service runs with a dual host, on a highly available, Flexisip proxy server deployment.

Servers[edit]

Free and open-source license[edit]

Cipango SipServlets 1.1 application server
Issabel, fork of Elastix
Kamailio, formerly OpenSER^[1]
Mobicents Platform (JSLEE[2] 1.0 compliant and SIP Servlets 1.1 compliant application server)
OpenSIPS, fork of OpenSER
SIP Express Router (SER)

Proprietary license[edit]

3Com VCX IP telephony module: back-to-back user agent SIP PBX
3CX Phone System, for Windows, Debian 8 GNU/Linux
Aastra 5000, 800, MX-ONE
Alcatel-Lucent 5060 IP Call server
Aricent SIP UA stack, B2BUA, proxy, VoLTE/RCS Client
Avaya Application Server 5300 (AS5300), JITC certified ASSIP VoIP
Bicom Systems IP PBX for telecoms
Brekeke SIP Server, SIP proxy, SIP registrar, SIP NAT, TCP/UDP
Brekeke PBX, SIP PBX for service providers and enterprises
Cisco SIP Proxy Server, Cisco unified border element (CUBE), Cisco Unified Communication Manager (CUCM)
CommuniGate Pro, virtualized PBX for IP Centrex hosting, voicemail services, self-care, ...
Comverse Technology softswitch, media applications, SIP registrars
Creacode SIP Application Server Real-time SIP call controller and IVR product for carrier-class VoIP networks
Dialogic Corporation Powermedia Media Servers, audio and video SIP IVR, media and conferencing servers for Enterprise and Carriers.
Dialexia VoIP Softswitches, IP PBX for medium and enterprise organizations, billing servers.
IBM WebSphere Application Server - Converged HTTP and SIP container JEE Application Server
Interactive Intelligence Windows-based IP PBX for small, medium and enterprise organizations
Kerio Operator, IP PBX for small and medium enterprises
Microsoft Lync Server 2010 & 2013
Mitel Communications Director
NEC SV7000 back-to-back user agent SIP PBX
NEC UNIVERGE 3C Unified Communications and Collaboration software
Nokia Siemens Networks hiQ8000
Nortel SCS500
Nortel SIP Multimedia Communication Server 5200
Objectworld UC Server
Oracle Communications Converged Application Server (OCCAS)
Oracle WebLogic SIP Server
REVE Systems Mobile VoIP, Class 4/5 Softswitch with integrated billing and Bandwidth Optimization products
Spirent SIP Server Platform
ShoreTel IP phone systems with unified communications and contact center built in
Snom One free/blue/yellow (Snom acquired and renamed pbxnsip) (SIP)
Speedflow Communications VoIP class 4/5 softswitches with integrated billing, transcoding, SIP-H.323 converter.
Sterlite Technologies Neox IPPBX, IMS - ISC, Dial Center - OmniChannel Call Center, IVR products
Sun Microsystems Sun GlassFish Communication Server
Tadiran Telecom Coral Ipx family and Aeonix softswitch
Tandberg Video Communication Server - SIP application server, media server and H.323 gateway
TrueConf Server - video conferencing server software, SIP gateway
Unify OpenScape Voice, OpenScape 8000 SIP softswitch, mediaserver, ... (SIP)
Voice Elements Inventive Labs' .NET Voice Development software and SIP stack platform.
Wildix WGW series Unified communication platform up to 5000 users on a single server. Up to 65535 users on WMS network
Zultys MX250/MX30 IP PBXs for SMB and enterprise

Clients[edit]

Free and open-source license[edit]

Empathy, using GTK+ libraries and Telepathy framework, GPL
Jami, with GTK+/Qt GUI, also supports IAX2 protocol, for Linux, OS X, Windows GPL
Jitsi, a Java VoIP and Instant Messaging client with ZRTP encryption, for FreeBSD, Linux, OS X, Windows; LGPL
KPhone, using Qt libraries, GPL, for Linux
Linphone, with a core/UI separation, the GUI is using GTK+ libraries, for Linux, OS X, Windows, and mobile phones (Android, iPhone, Windows Phone, BlackBerry)
MicroSIP, lightweight softphone, using PJSIP stack, for Windows
Telephone, OS X softphone written in Cocoa/Swift
Twinkle, using Qt libraries, GPL, for Linux
Yate client, using Qt libraries,^[2] GPL^[3]

Proprietary license[edit]

Blink, for Mac
CounterPath Corporation Bria desktop and mobile carrier-class, enterprise-grade VoIP applications
Librestream's 2500 Camera, 5000HD camera, Onsight Cube (wearable/modular camera), Onsight Connect (Windows, iOS, Android).^[4]
LifeSize Desktop, for Windows
Phoner and PhonerLite, for Windows, Voice: G.711, G.722, G.726, GSM, iLBC, Speex, Opus; security: TLS, SRTP, ZRTP
Polycom PVX, for Windows. Voice: G.711, G.722, G.722.1, G.728, G.729A, Siren Codec; Video: H.261, H.263, H.264; Data: T.120, People+ Content, H.239, H.323 Annex Q far-end camera control
Windows Messenger versions 4 and 5 (not to be confused with Windows Live Messenger or MSN Messenger which do not support SIP)

Discontinued[edit]

eyeBeam, discontinued in 2018
QuteCom, formerly named OpenWengo, using Qt libraries, GPL, for Windows, Mac, and RPM- DEB-based Linux,^[5] discontinued in 2016
Gizmo5, formerly PhoneGaim, discontinued in 2011

Mobile clients[edit]

Free and open-source license[edit]

Jami for Android, iOS; GPL v3
Linphone for Android, BlackBerry, iPhone, Windows phone; GPL v2
Sipdroid for Android, GPL v3

Proprietary license[edit]

Acrobits for iOS and Android
CounterPath Corporation Bria Mobile for iOS and Android

Discontinued[edit]

CSipSimple for Android, GPL v3, discontinued in 2019^[6]

Session border controllers[edit]

Acme Packet Session Director
Audiocodes Mediant
Genband Quantix SBC
Ingate Systems Ingate SIParators
Metaswitch Perimeta

Enabled firewalls[edit]

Check Point VPN-1 firewalls, include complete SIP support for multiple vendors
The fire

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