between two entities. In aviation, the typical usage is Air Traffic Controller communicates with airplanes about the information of the ATC when voice communication is not possible due to distance. In military, data link also includes the communication among different aircrafts. Exchanging data, especially low bandwidth data isn't particularly difficult, but about to do "自己看到的镜像都传给其他" involves a lot more. This usually require higher bandwidth, and complicated protocols. I don't know what China has, however, since traditionally China was pretty behind in RF technology till later years. It is very unlikely to have very sophisticated data link capability. However, the main question that I have is: data link, like Link 16, on the aircrafts are very useful in coordinating between ground/sea/air (with Surveillance planes like E-2/E-3 and so on), but not very useful for dogfights. If two-to-two in this case, their range is close enough, that two j-10 radars will pick up the same things, what make the data link so special that determined the outcome?