Tham khảo tài liệu 'suse linux 10 for dummies phần 7', công nghệ thông tin, hệ điều hành phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | Chapter 10 E-Mailinạ IM-inạ and Using IP Phone in SUSE 165 Making ỈP Telephone Calls in SUSE Linux You may have heard about VoIP Voice over Internet Protocol a technology that converts analog voice signals into digital data packets that can then be sent over the Internet to its destination where the data packets are converted back to analog audio. VoIP also known as IP telephony enables voice communications over the Internet and applications are available to make such IP telephone calls from your SUSE Linux system. As you might guess from my rough description of VoIP you need a way to get your voice into the computer and listen to the voice signals from the person you are talking to. Your system s sound card with a microphone plugged in for voice input and the speakers attached to the sound card can take care of the audio side of the phone call. If you want to routinely make IP phone calls you may want to buy a headset with a built-in headphone and microphone. Internet telephones use one of two protocols and SIP Session Initiation Protocol for sending voice over IP networks. is an older protocol that s supported by Microsoft Netmeeting and GnomeMeeting available in SUSE Linux s GNOME desktop . SIP is an Internet standard protocol and many IP telephony devices and applications support it. For example KPhone and Linphone two IP telephony programs included in SUSE Linux support SIP. For SIP-compliant IP telephony applications you have to use a SIP URL with the syntax sip user@hostname or sip user@IPaddress where IPaddress is an IP address to identify the person you are calling. A SIP phone application can call another directly provided that both applications can reach each other on the IP network. For example on my home LAN I can start KPhone on a Linux PC with the IP address and use the URL sip naba@ to call a user on another system on the LAN. Similarly you can call anyone else running a SIP phone application on a system with a .
