LAS VEGAS — This week’s 20th Black Hat USA conference and the 25th DEF CON hackers conference here offer cybersecurity researchers and technologists a chance to exchange notes on their often obscure trade, but they also provide a rare venue for discussion between corporate and government officials on one side and in-the-trenches cyber practitioners on the other.

Black Hat began Saturday with training sessions for cyber pros, and the main program runs Wednesday and Thursday. It’s followed immediately by the DEF CON hackers’ convention, which runs July 27-30.