From: bok118@zonnet.nl   
      
   On Fri, 04 Dec 2009 21:21:31 +0800, Hongyi Zhao   
    wrote:   
      
   >I want to judge some remote hosts online or not quickly over WAN. I've   
   >learned that ping command will not work in this case if the icmp ack   
   >is blocked locally by firewall.  Are there some command line tools to   
   >do this job.   
      
   That would depend on what that host is supposed to do on the WAN.   
   If it is some kind of server, you could send it a request and   
   look for it's answer.   
      
   If the host is a common user PC, it shouldn't provide any way to   
   detect it's presence to an unsollicitated party ;-)   
   Unless it supports PING, that is. Read   
   https://www.grc.com/x/ne.dll?bh0bkyd2   
   (GRC Shields Up) for a further explanation.   
      
   --   
   met vriendelijke groet,   
   Gerard Bok   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)