.dd was the assigned

country code top-level domain A country code top-level domain (ccTLD) is an Internet top-level domain generally used or reserved for a country, sovereign state, or dependent territory identified with a country code. All ASCII ccTLD identifiers are two letters long, and al ...

(ccTLD) for the

German Democratic Republic German(s) may refer to: * Germany (of or related to) ** Germania (historical use) * Germans, citizens of Germany, people of German ancestry, or native speakers of the German language ** For citizens of Germany, see also German nationality law **G ...

(East Germany). It was chosen based on the

ISO 3166-1 alpha-2 ISO 3166-1 alpha-2 codes are two-letter country codes defined in ISO 3166-1, part of the ISO 3166 standard published by the International Organization for Standardization (ISO), to represent countries, dependent territories, and special areas ...

code for the

, the letters coming from the

German German(s) may refer to: * Germany (of or related to) **Germania (historical use) * Germans, citizens of Germany, people of German ancestry, or native speakers of the German language ** For citizens of Germany, see also German nationality law **Ge ...

name of the country, '. In accordance with

IANA The Internet Assigned Numbers Authority (IANA) is a standards organization that oversees global IP address allocation, autonomous system number allocation, root zone management in the Domain Name System (DNS), media types, and other Intern ...

policy, .dd was therefore available to be assigned as the

(ccTLD) for East Germany. However, this was never done, and so .dd was never added to the

root nameserver A root name server is a name server for the root zone of the Domain Name System (DNS) of the Internet. It directly answers requests for records in the root zone and answers other requests by returning a list of the authoritative name servers ...

s. Its only use was internally in an isolated network among the universities of

Jena Jena () is a German city and the second largest city in Thuringia. Together with the nearby cities of Erfurt and Weimar, it forms the central metropolitan area of Thuringia with approximately 500,000 inhabitants, while the city itself has a po ...

and

Dresden Dresden (, ; Upper Saxon: ''Dräsdn''; wen, label= Upper Sorbian, Drježdźany) is the capital city of the German state of Saxony and its second most populous city, after Leipzig. It is the 12th most populous city of Germany, the fourt ...

. With the

reunification of Germany German reunification (german: link=no, Deutsche Wiedervereinigung) was the process of re-establishing Germany as a united and fully sovereign state, which took place between 2 May 1989 and 15 March 1991. The day of 3 October 1990 when the Ge ...

, East Germany became part of the

Federal Republic of Germany Germany,, officially the Federal Republic of Germany, is a country in Central Europe. It is the second most populous country in Europe after Russia, and the most populous member state of the European Union. Germany is situated betwee ...

(West Germany), which had already been assigned the ccTLD

.de .de is the country code top-level domain (ccTLD) for the Federal Republic of Germany. DENIC (the Network Information Centre responsible for .de domains) does not require specific second-level domains, and there are no official ccSLDs under .d ...

. The ISO 3166-1 code "DD" was withdrawn in 1990.Changes in ISO 3166-1 (annotated summary of RIPE documents)
/ref>

References

External links

* discussion on Usenet (German) Country code top-level domains Mass media in East Germany {{compu-domain-stub sv:Toppdomän#D