IChat using AIM

Question

My friend is in korea. He can iChat with another friend in Mexico but not with me... I'm getting some kind an error. We tired the bandwith limit, etc and nothing. He can chat with Mexico and I can chat with mexico, but I can not chat with him in Korea.
Please any advise?

Answer 1

This can be caused by a Duplex mismatch,
A duplex mismatch is a common cause of end-to-end performance problems. It is often manifested by a connection that will work at low speed, but drops packets when high-speed flows are attempted (usually with some traffic flowing in the opposite direction). It is due to a failure in the protocol used to negotiate whether an internet connection can have traffic flowing only in one direction at a time (half-duplex) or in both directions at the same time (full-duplex). It is apparent that a mismatch occurs when one machine is set at full-duplex and another at half-duplex. What is not so obvious is that:
When auto-negotiate meets auto-negotiate, the transmission rate is full-duplex;
When half-duplex meets auto-negotiate, the rate is half-duplex.
In both cases, no problems occur. However, when auto-negotiate meets full-duplex, auto-negotiate converts to half-duplex and not, as you would expect, to full-duplex -– the auto-negotiation capability is programmed to assume half-duplex unless it meets another machine set at auto-negotiate.
If, for any reason, one side believes it is full-duplex, and the other half-duplex, the side that is full-duplex may send packets when the other side is not expecting them, and those packets are dropped. To avoid these problems, a common fix is to always force both sides to auto-negotiate (because most new devices come preset this way).
233C2D   Mac OS X (10.4.9)