The 21-year-old is regarded as one of the brightest talents in European football after making 85 appearances in the last two seasons for the Bundesliga giants.
"Philipp has helped me a lot and I am grateful for this," Alaba told reporters. "He has played for such a long time at a very high level, and right or left he was the best or one of the best players in the world. You can see this season after season.
"As a young player Franck Ribery looked after me. It was him who said 'come here my boy'. He looked out for me both on and off the pitch.
"As I lived in the boarding school, he often picked me up and we went out for dinner. Obviously you are grateful about those things and want to give something back. We get along very well."
Alaba joined Bayern in 2008 from Austria Wien.