The glossary below contains many of the terms you will find in common use throughout the Symantec Security Response website. Please refer to this list to find definitions of terms and answers to other Internet security-related questions.

Smart DNS

A smart traffic filtering option that allows a Domain Name System (DNS) client to resolve a domain name from a DNS server while providing protection against DNS attacks from the network. This option blocks all Domain Name System (DNS) traffic except outgoing DNS requests and the corresponding reply. If a client computer sends a DNS request and another computer responds within five seconds, the communication is allowed. All other DNS packets are dropped. Smart DNS does not block any packets; blocking is done by the normal security rule set.