Kamaraju S Kusumanchi wrote:
Martin wrote:Hello, I find out that gaim is able to use text messaging with many programs. I want to use voice messaging (use it as phone) when other person is using Yahoo Messenger on MS Windows. Is there some program for debian that can do this? Friend told me that he is using Yahoo Messenger on dial-up connection. I only have 33k dial-up too and am hoping to be able to use it. How much bandwith does protocol for transferring voice need? MartinAFAIK, gaim can't do voice chat. Use Skype for voice chat. Skype works both in Linux, Windows. raju
In the US, a 56k dialup running at 53k (max allowed by law, and rarely achieved in practice) gives you just about the necessary bandwidth for voice over IP, *and nothing else*. Overhead, or some other piece of software phoning home, will just about kill it. POTS (plain old telephone service) lines are really a voice medium, it's kind of ironic that it's hard to do voice over a voice line.
50,000 bps - 20% for overhead = 40,000 bps. 40,000 divided by 3 is about 13,000 Hz max frequency, one channel of FM-quality sound. For voice, 8,000 Hz will do. Going the other direction, 3 x 8,000 = 24,000 bps. 24,000 is 80% of 30,000. So, using these assumptions, 33k dialup for VOIP is just barely feasible. Using compression, it should be possible.[0]
I expect it would work with the right software. As Kamaraju wrote, gaim is not the place to start.
Mark Allums0. Not a voice-over-IP expert, and yes, I *have* heard of Nyquist. Three samples at the highest desired frequency gives better results, especially for voice. What modulation does Skype use? Some type of delta modulation would be my guess for dialup, but I have no real idea.