DNS Flag Day

DNS Flag Day

January 31, 2019 0 By Nurul Ausah

Tomorrow is the 1st February 2019. Its is a DNS Flag Day. This day could a disastrous day to your website user especially to the ecommerce website users. On the day all the DNS Software and even the service providers will be going to supporting a few DNS systems that are not in compliance with DNS standards. The changes are coming to the DNS systems that are not completely complied with EDNS standards.

The current DNS is unnecessarily slow and inefficient because of efforts to accommodate a few DNS systems that are not in compliance with DNS standards established two decades ago.


They also stated that this DNS System change will make most of DNS Operation slightly more efficient, and also allow operations to deploy new functionality, including a new mechanism to protect against DDoS attack.

World of DNS

The DNS system will translate the fully qualified domain name to ip address. When the ip address is valid the browser will directed your user view to the Website of the domain name.

DNS Message Header

The DNS Message Header has certain flags such as QR Flag, AA, TC and etc. There also a section such as additional info, query, answer, question and etc. Recently added section which OPT PSEUDO which is new and contains the EDNS. The EDNS will have a version number which currently is 0, flags and UDF. This section will increase the security. Previously DNS will ignore the EDNS, but recently it not allow anymore as the EDNS already forcely apply in the DNS.

ISC is testing EDNS compliance because the lack of proper EDNS compliance impacts the deployment of new DNS features. In particular we wish to deploy Domain Name System (DNS) Cookies [RFC 7873] which requires Unknown EDNS Options to be correctly handled by all servers.


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