Once you’ve got your SOA all sorted – IIS can run out of available connections pretty quick due to things like Web Services calling other WebServices on the same box using up valuable connections.
Here’s a great MSDN Article that gives you the tech. details so your WebServices will hum.
http://msdn.microsoft.com/library/default.asp?url=/library/en-us/dnpag/html/scalenetchapt10.asp