Definition: Zones are just different Logical Path (URL) to the same web application with different authentication methods.

If you want to present the same web application to different type of users using different URL and different authentication mechanism then you create a Zone or Extend an existing Web Application.

• Each web application can have maximum 5 zones
  • Default
  • Intranet
  • Internet
  • Extranet
  • Custom
• Each zone has its own IIS website
• Each zone has a different URL configured
• Blob and distributed cache can be configured differently for each zone
• Each zone has its own port number and protocol (http/https)
• As mentioned earlier, different authentication method can be applied to different zone. i.e. Forms Based Authentication in Internet and Windows authentication in default zone.
• You cannot use the same zone again for the same web application. Like if you have created an Intranet zone for a web application, you cannot create an Intranet zone again for the same web application.
• Each zone uses the same web application and same content, stored in the content database.