In this article, I would like to share the procedure to configure the alternate access mappings using Central Administration in SharePoint 2013.

Uses of Alternate access mappings

Procedure to Configure alternate access mappings

Use the following procedure to configure alternate access mappings using Central Administration.

Step 1: Go to the Central Administration using a farm administrator account as shown below.

central administration

Step 2: In Central Administration, click system settings from the left navigation. Then you will be navigated to the system settings page.

system settings

Step 3: On the system setting page, in the “Farm Management” section select the “Configure Alternate Access Mappings”.

Farm Management

Step 4: When you click on the “Configure alternate”, you will be navigated to the Alternate access settings page as shown below, then click on the “Edit Public URL's”.
Edit Public URL

Step 5: On the “Edit public zone URL's” page, select the site collection from the alternate access mapping collection from the drop down as shown below:
Edit public zone URL

Step 6: When you click on the change alternate access mapping collection option, you will get a pop-up to choose the site collection as shown below. There you can select the site collection that you want to add the URLs in Intranet, Internet, custom and Extranet.
site collection

Step 7: After selecting the site collection, you will have the option to add the URLs as shown below.
URL

Step 8: Then give the URL in the text boxes, which zone you want to access the site and then click Save.
Here I provided the Internet URL for public access.
Internet URL for public access

Summary

In this article we have explored how to configure the alternate access mapping for a SharePoint web application using Central Administration.