idna implements IDNA2008 (Internationalized Domain Names for Applications), defined in RFC 5890, RFC 5891, RFC 5892, RFC 5893 and RFC 5894.
The current implementation provides a nif binding the ICU IDNA api.
1> A = idna:to_ascii(<<"www.詹姆斯.com"/utf8>>).
<<"www.xn--8ws00zhy3a.com">>
2> idna:to_unicode(A).
<<"www.詹姆斯.com"/utf8>>