expression
Honorific phrase used to acknowledge shared knowledge with the listener. Often used as a preface before stating something the listener is expected to know.
ご存知の通り、来月から新しい制度が始まります。
As you know, the new system will start next month.
ご存知の通り、彼はこの分野の専門家です。
As you are aware, he is an expert in this field.
ご存知 is the honorific noun meaning 'knowing' or 'knowledge', while ご存知の通り is the full phrase meaning 'as you know'.
Combination of the honorific prefix ご, the noun 存知 (ぞんじ, 'knowing'), the possessive particle の, and the noun 通り (とおり, 'as, in accordance with').