In DNS, a default Time to Live (TTL) value that is set in seconds and used with all resource records in a zone. This value is set in the start of authority (SOA) resource record for each zone. By default, the DNS server includes this value in query responses. It is used to inform recipients how long they can store and use resource records, which are provided in the query answer, before they must expire the stored records data. When TTL values are set for individual resource records, those values override the minimum TTL.