SIP UAs – referencie

3CX phone for Windows

http://www.3cx.com/VOIP/voip-phone.html

Blink

http://icanblink.com/

Zfone

http://zfoneproject.com/

Mizutech softphone

http://www.mizu-voip.com/

OfficeSIP Softphone

http://www.officesip.com/softphone.html

OfficeSIP messenger

http://www.officesip.com/messenger.html

Free replacement to Office Communicator.

Zoiper

Offer Comunicator and Classic versions

http://www.zoiper.com

miniSIP

http://www.minisip.org/

Focus on security features

Sippy B2BUA

http://www.rtpproxy.org/wiki/WikiStart

Back 2 back User agent

SJPhone

http://www.sjlabs.com/sjp.html

Xlite

without presence

http://www.counterpath.com/

GizmoProject

http://www.gizmoproject.com/

ExpressTalk

http://www.nch.com.au/

eKiga

http://ekiga.org/

KCall

http://kcall.basyskom.org/

Kphone

http://sourceforge.net/projects/kphone

Linphone

http://www.linphone.org/

OpenWengo 

http://www.openwengo.org/

PhoneGaim

http://www.sipphone.com/phonegaim/

PJSUA

http://www.voip-info.org/wiki/view/PJSUA

TudoMais

http://sourceforge.net/projects/tudomais

Twinkle

http://www.twinklephone.com/

SIP Communicator

http://sip-communicator.org/

XMeeting

http://xmeeting.sourceforge.net/

wxCommunicator

http://wxcommunicator.sourceforge.net/