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Rest in peace: Itojun, IPv6 pioneer

Itojun: Rest in peace

It is with regret that ICANN mourns the passing of Jun-ichiro Hagino, better known as Itojun, aged 37.

Itojun was a pioneer of IPv6 technology, best known for his extensive work in introducing the protocol into the BSD network stacks.

In 1998, he helped start and became one of the lead researchers in the Japanese KAME project. KAME recognised that the new IPv6 specification – which had been designed to allow the Internet to expand unrestricted into the future – needed to be carefully integrated into the existing operating systems that much of the Internet’s backbone runs on.

He and his team went back to basics and dug into the BSD source code in order to see how the existing IPv4 protocol worked within it (finding a few bugs that had gone unnoticed on the way) before using that knowledge to integrate IPv6 as seamlessly as possible.

It was the start of a long period of advocacy over IPv6 for Itojun, who felt that those who developed technology that allowed them to continue using IPv4 were wasting their time. “I had more than enough troubles with NAT,” he said in a 2001 interview. “I really need a simpler solution. That is, IPv6. Internet technology has to be much more stable, simple, and robust.”

As well as making its integration possible, Itojun vigorously tested IPv6, expanded its integration into operating systems and other software as far as he could, deployed countless IPv6 networks and taught as many engineers as possible about the technology.

A highly respected and liked member of the WIDE Internet technology research group, and a self-confessed workaholic, Itojun was awarded a Bachelor in Electrical Engineering, then a Masters in Computer Science, and finally a PhD degree from Keio University, before taking a job at, among others, Sony where he worked on the operating system that ultimately ended up in the AIBO robot dog.

He became in his time an associate professor at the Japan Advanced Institute of Science and Technology, a co-chair of an IPv6 working group, and a member of the Internet Architecture Board. He wrote a book on IPv6 called IPv6 Network Programming.

On his personal webpages, Itojun listed his favourite quote as coming from the movie Bladerunner: “The light that burns twice as bright burns half as long.”

Sadly, that quote would prove to be true about Itojun’s own life. But through the ground-breaking work that he carried out in relation to Internet Protocol version 6, work that will enable the Internet to continue on its extraordinary trajectory, billions of people across the globe will in future have good reason to be grateful for “government certified geek” Jun-ichiro “itojun” Hagino.

Jun-ichiro Hagino died on 29 October 2007 and was buried yesterday, 7 November 2007, in Tokyo, Japan.


    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."