How to securely submit a high score in a front end game to prevent post hijacking [closed]

Answer 1

What about something like this:

1. Have the server send a nonce - 'hash-signed' by server's secret key and timestamp etc.,
2. Have a hash based on some internal datastructures + client key and send it to server periodically
3. Do this over SSL

And @iamkrillin beat me to it...but I am still gonna post it :)