How to create a multiplayer time based score board

Would you know how I can go about creating a time based score board for a multiplayer game?

it is based on how long the player survives in game; the longer you survive the higher your score.

Would highly appreciate the help!

Which part do you need help with, getting the scoring to work based on survival time, or creating a scoreboard to display those times, and what is your obstacle to being able to do it?