Any cable or DSL hookup is good (never use dial-up for web conferencing.) For your audio linkup, you can either use an Internet-based technology called VoIP, or a telephone, depending on the software your conference is using. VoIP stands for Voice over Internet Protocol. It is like a telephone, but instead of being sent analogically through the phone lines, audio is sent digitally via the Internet, at a cost much lower than traditional long distance. In either case, it is recommended that you utilize a comfortable headset with earphones and a microphone. That way, your hands will be free, you will be more comfortable, and your face will be seen by the web cam.
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