Thank you for your comment. The problem is not a network down. They blocked traceroute and ping for their internal network. ;< I didn't think about that. There is no way to confirm network connection except real WWW traffic. Thank you, again. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Hyun Ryu Network Engineer/Applications Engineering Norlight Telecommunications Tel. +1.262.792.7965 Fax. +1-262.792.7733