Skip to main content

ICANN's Response to RSSAC001 for its L-Root Service

Reinvigorated RSSAC

ICANN's Root Server System Advisory Committee advises the Board on the operational requirements for the root nameserver system. Like all ICANN structures, it is regularly reviewed for its effectiveness and improvements to its operations are implemented. Since the most recent review, RSSAC has formed a Caucus for the experts responsible for producing its work. They have recently delivered two recommendations to the Board: RSSAC001, which set out some Service Expectations of Root Servers and RSSAC002, which is an advisory on Measurements of the Root Server System. RSSAC002 was published in late 2014 and RSSAC001 was published today, in coordination with RFC7720, which is a complementary IAB document about the Root Server System.

Public statement of how ICANN meets the expectations

ICANN operates L-Root, one of the 13 root DNS servers ( providing authoritative DNS information about Top Level Domains. We are pleased to say that L-Root meets all of the service expectations documented in RSSAC001 and we have published a simple web page that describes what we do for each of the sets of expectations. Our response provides links to authoritative information about the different aspects of our L-Root service, ranging from software selection, routing, site locations, and through to operational statistics.

Maintenance and updates

We constantly measure and review the way we deliver the L-Root service and plan and execute changes that make sure we can continue to deliver the high level of service required and expected of a root server. This means that we plan, test and deploy changes to the service in a structured way on an ongoing basis. Consequently, we will also be reviewing and updating our RSSAC001 response on a regular basis, to make sure that the public is well-informed about the way we go about delivering this important service. It is living web page and will be reviewed and updated at least twice a year.

What to know more or become involved in RSSAC?

If you are interested in finding out more about or participating in the RSSAC Caucus, you can read find out more on its website.

If you would like to learn more about L-root or even consider hosting an L-root instance in your own network, please see the DNS Engineering website or have a chat with one of our Global Stakeholder Engagement team.


    Domain Name System
    Internationalized Domain Name ,IDN,"IDNs are domain names that include characters used in the local representation of languages that are not written with the twenty-six letters of the basic Latin alphabet ""a-z"". An IDN can contain Latin letters with diacritical marks, as required by many European languages, or may consist of characters from non-Latin scripts such as Arabic or Chinese. Many languages also use other types of digits than the European ""0-9"". The basic Latin alphabet together with the European-Arabic digits are, for the purpose of domain names, termed ""ASCII characters"" (ASCII = American Standard Code for Information Interchange). These are also included in the broader range of ""Unicode characters"" that provides the basis for IDNs. The ""hostname rule"" requires that all domain names of the type under consideration here are stored in the DNS using only the ASCII characters listed above, with the one further addition of the hyphen ""-"". The Unicode form of an IDN therefore requires special encoding before it is entered into the DNS. The following terminology is used when distinguishing between these forms: A domain name consists of a series of ""labels"" (separated by ""dots""). The ASCII form of an IDN label is termed an ""A-label"". All operations defined in the DNS protocol use A-labels exclusively. The Unicode form, which a user expects to be displayed, is termed a ""U-label"". The difference may be illustrated with the Hindi word for ""test"" — परीका — appearing here as a U-label would (in the Devanagari script). A special form of ""ASCII compatible encoding"" (abbreviated ACE) is applied to this to produce the corresponding A-label: xn--11b5bs1di. A domain name that only includes ASCII letters, digits, and hyphens is termed an ""LDH label"". Although the definitions of A-labels and LDH-labels overlap, a name consisting exclusively of LDH labels, such as"""" is not an IDN."