Alfred Pennyworth (Earth-1: Pre-Crisis)

"Oh and the WIFI password is Alfred."

- Kate Kane to Oliver Queen, Barry Allen and Kara Danvers

Alfred Pennyworth was a close friend and ally of Bruce Wayne and the father of Julia Pennyworth.

Early life
At some point, Alfred learned that Bruce Wayne was the vigilante known as Batman and had a daughter called Julia.

Trivia

 * The WIFI password at Wayne Tower is likely named after him.