If turn on IP check 1) player1 ID+PW ->server 2) server record IP 3) server sessionID ->player1
4) player1 request with sessionID ->server 5) server recognize IP 6) server work success or 4) player2 request with sessionID ->server 5) server recognize IP 6) server work fail
If close IP check 1) player1 ID+PW ->server 2) server sessionID ->player1 3) player(x) request with sessionID ->server 4) server work success
每一次登入都會給不同的sessionID
換言之, IP check系統關閉後,你可以在不同的地方使用同一個sessionID without login