Also for 'Umar as in Daruqutni and for Abu Bakr as in Abu Dawood. The earlier Muslims did not specify it to a Sahabi alone or to the ahl al Bayt as some of the misguided do. So al-Qari al-hanafi wrote in the Sharh of al-Fiqh al-Akbar: "Peace (salam) is the greeting of muslim nation. There is no difference between saying as salamu alaykum, and alayhi salam. But, it's not good to say "Ali alayhi salam" due to this being the word of people of innovation". This link might help: http://www.islamweb.net/emainpage/in...waId&Id=163193