DNS provides a set of functions for different scenarios.

You can select a type of function based on Table 1 to suit your network scenario.

**Table 1** Scenarios where DNS is required
Function	Scenario	Reference
Public domain name resolution	Domain names are mapped to the public IP addresses of web servers or web applications on the Internet so that end users are routed to your website or application.	Configuring a Public Zone
Private domain name resolution	Domain names are mapped to the private IP addresses within the VPCs for accessing cloud resources or cloud services over a private network.	Configuring a Private Zone
Reverse resolution	EIPs are mapped to domain names, which is often used by email servers against spammers.	Configuring a PTR Record

Before You Start