Combine IIS HTTP Compression and Output cache in ASP.NET

• 1 Add Dynamic Content Compression Role Service to IIS
  
• 2 Enable compression in the IIS Manager (static and/or dynamic)
  
• 3 Enable or disable compression at site/folder/file level
  
• 4 Find Windows\System32\inetsrv\config\applicationHost.config file and edit this line:
  <urlCompression dynamicCompressionBeforeCache="true" ... />
  
• 5 To support really old browsers add
  <%@ OutputCache Duration="300"
  VaryByContentEncoding="gzip;deflate" %>
  

References

• http://www.codeproject.com/Articles/242133/Making-the-most-out-of-IIS-compression-Part-1-conf
• http://weblogs.asp.net/owscott/archive/2009/02/22/iis-7-compression-good-bad-how-much.aspx