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Update of DENIC Domain Guidelines effective 16 November 2010


Characters permitted in .de domains include "ß"

Effective 16 November 2010, DENIC allows the LATIN SMALL LETTER SHARP S (ß) as an independent character in .de domain names. Thus, domains such as "straße.de" (German for "street") can be registered. Permitting "ß" as a character in .de domains, DENIC follows the revised standard for Internationalized Domain Names in Applications (IDNAbis) and applies it to the .de zone. Since 4 August 2010, the IDNAbis standard allows the Latin small letter sharp s – also known as "Eszett" or "sharp s" ("ß") – to be used as part of a domain name.

DENIC amends the Domain Guidelines and includes the Latin small letter sharp s in the list of valid characters for .de domains. The rules regarding preferential registration for holders of existing domains with the letter combination “ss” cease to apply. ß-domains are subject to the general registration standard of the German ccTLD, which follows the "first come, first served" principle. The new ß-domains will be covered by DENIC's information services such as the whois service immediately after registration.

Parties interested in registering an ß-domain should contact a provider or DENICdirect, in case adminstration of the domain is desired to be undertaken without an intermediary, by DENIC. For this purpose please take into account the specific registration information for DENICdirect.

Registrants of ß-domains have to ensure that the registration and intended use of the domain does not infringe anybody else’s rights nor break any general law.

Details about the registration of a domain can be found in the DENIC Domain Guidelines.

Changes Brought About by the New Standard

According to the previously applicable IDN standard, the letter "ß" was converted into an ASCII-compatible format to enable the Domain Name System (DNS) to process it and to make it suitable for use in domain registration. Thus, when a user entered a domain containing the Latin small letter sharp s, the web browsers automatically converted the "ß" into "ss". So domain names like "straße.de" automatically became "strasse.de". It depended on the browser type if this conversion was visible to the user in the address line. On the contrary the new IDN standard stipulates that "ß" shall be a separate character and shall no longer be mapped to "ss". This rule is now applied by the DNS. So "straße.de" and "strasse.de" will be two separate domains in the future. As a result of the new rule, applications based on the former IDN standard are no longer compatible with the new standard. This is called lack of backwards compatibility.

Consequences of the Lack of Backwards Compatibility

As regards the user, the conversion may bring about unexpected results during a transition period because most web browsers and e-mail clients are still based on the old IDN standard. Thus, it depends on the software that is used, to which domains a user will be directed when entering a domain name that includes an "ß". While browser versions that are based on the new standard will display exactly the page the user has entered, older browser versions will always direct the user to the domain with “ss”. However, this domain may not necessarily be identical with the queried "ß"-domain, regardless whether both domains are registered by one and the same holder or not. DENIC has no means to influence vendors of such browsers as to when they will update their applications to make them compatible with the amendments of the IDN protocol. Thus, DENIC recommends parties interested in ß-domains to take this technical uncertainty into consideration with regards to the use of the domain.