There are so many factors

1. It doesn't matter of your offered speed, but it does matter of your real speed. It totally dependes on your Phone line quality and the distance you and DSLAM(the switch). The actual speed could be worse, you have to test it. Most ISP offer that testing from web or you can search it.

2. The end-to-end connection may vary from call to call. You may experience longer delay depends on current routing path. This you cannot control.

3. Your IM software really matters. Besides you may not use image quality term but video quality instead. You have to balance perframe quality vs frame rate. You won't feel happy if you have clear view of 640x480 image but only with 0.1fps. For a video chat, 176x144 is good enough if you have 8 fps. You can calculate how much you would send vs network speed with presents of compression. It won't need much.

4. You also need to consider the synchronization between voice and video because normally they are transmitted in different package.

So, choosing right IM software is more important than you upgrade to a higher speed. Skype and gtalk are good. Don't use MSN and Yahoo, they are sucks.

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• Thanks a lot for your answer. You are really -xa5her22- ♂ (240 bytes) () 10/13/2006 postreply 12:18:52

• The answer is NO -德州老外- ♂ (1015 bytes) () 10/13/2006 postreply 13:45:56

• Thanks a lot for Ur answer. I do not know too much of -xa5her22- ♂ (428 bytes) () 10/14/2006 postreply 06:50:36