You can use zones to enforce different access and policy conditions for group of users. Each Web application can have a maximum of 5 zones. The 5 possible zones are:· Default: · Intranet · Internet · Custom · ExtranetWhen you create a Web application, the Default zone is created.
Add web parts directly to a master page or page layout. This means content authors cannot modify the web parts. Add web parts to zones on page layouts, but restrict those zones to only the default web parts that you add.
Each Web application can have a maximum of 5 zones.The 5 possible zones are: When you create a Web application, the Default zone is created. You can then extend the Web application to create other zones.
Open Central Administration site - Application Management - [under Application Security] Policy for Web Application - Add Users-Zone: Extranet-NEXT-Type User Name [click on the icon below it to check]-Permission: Full Control-Finish. Repeat the same to add all the target users.