典型的なネットワークがだめな時の症状ですね。
すぐ閉めてくる。

%telnet live28.2ch.net 80
Trying 206.223.151.120...
Connected to live28.2ch.net.
Escape character is '^]'.
Connection closed by foreign host.

%telnet live28.2ch.net 80
Trying 206.223.151.120...
telnet: connect to address 206.223.151.120: Connection reset by peer
telnet: Unable to connect to remote host