纠结的ubuntu，学校一有动作就上不了网。。

前段时间好容易用njit-client连上网了，这些天又不行了。。

[ ] Client: Start.
[1] Server: Request Notification!
    Client: Response Notification.
[2] Server: Request Identity!
[2] Client: Response Identity.
[3] Server: Request MD5-Challenge!
[3] Client: Response MD5-Challenge.
[1] Server: Request Identity!
[1] Client: Response Identity.
[172] Server: Request AVAILABLE!
[172] Client: Response AVAILABLE.
[4] Server: Failure.
E63047: The authentication client version is too old

{:19_700:}