If you wish to equip your website with the SMS service, the easiest way is to use a GSM device connected to the PC. Headwind GSM Modem Driver is a powerful SMS platform which helps you in building SMS services. The software provides two-way messaging, that is, from your PC to the subscriber and back. The short messages are sent from your SIM card and you do not need any internet gateways.
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Solution4VOIP VoipSwitch Solution4VOIP (The VOipSwitch Solution provider) is a complete IP telephony platform using which you can offer a variety of services such as: wholesale Voip termination, device to phone
3CX VOIP Phone for Windows Free VOIP / SIP phone. Use your PC as a phone. Works with any SIP/ VOIP provider/ phone service. Easy to use interface to transfer, forward calls or set-up conference calls. Free download from http://www.3cx.com
Uplink Skype to Sip Adapter Uplink connects SIP protocol VoIP calls to the proprietary Skype phone network. It works in both directions.
Express Talk VoIP Softphone Express Talk is software that works like a telephone to let you make calls from your PC. With Express Talk you can call anyone on the internet who has installed Express Talk (or any other SIP voip softphone). Calls are free.
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