Introduction to DNS

DNS, the abbreviation for Domain Name System, is a computer and network service naming system in form of domain hierarchy. DNS is designed for TCP/IP network to query for Internet domain names (e.g., www.xxxx.com) and translate them into IP addresses (e.g., 10.1.1.1) to locate related computers and services.

DNS provides the following functions:

• Server: Configures DNS servers and default domain names for the security appliance.
• Proxy: The security appliance acts as a DNS proxy server and provides proxy service for the connected PCs and other clients. Besides, the security appliance can also choose different DNS servers according to domain names.
• Resolver: Sets retry times and timeout for DNS service.
• Cache: Stores DNS mappings to cache to speed up query. You can create, edit and delete DNS mappings.
• NBT Cache: Displays NBT cache information.