From: Andy Shellam

>> By attempting to connect you will implicitly query DNS (which itself
>> is a connection to server).  
> No it's not - it's putting out a packet targeted at an IP address
> and hoping a server will answer - hence why multi-cast works for
> DNS because you're not directly connecting to a specified server,
> like you do with TCP/IP.  I believe it's similar for ping which is
> why it's used so commonly in monitoring applications.
> > If you're not online you won't be able to
>> resolve the domain name.  
> Exactly - so if all the OP wanted to check for was a working
> Internet connection, then DNS is a better way to go IMHO.

Both at home and at work there are caching DNS on the LAN. So a DNS
request may come back with a valid IP address when the WAN connection is
down. I still won't be able to connect to the remote site.

Bob McConnell

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