The Coordination Center for TLD .RU/.РФ and the “Поддерживаю.РФ” project conducted a study on the support of internationalized e-mail addresses (SMTP protocol extensions SMTPUTF8) by e-mail servers specified in the MX resource records of second-level domains registered in the .RU and .РФ. The presence of support for the SMTPUTF8 extension of the SMTP protocol announces the ability of the mail server to work with internationalized e-mail addresses. The study was conducted based on data for October 2022.
The results of the study showed that out of 638,458 delegated Cyrillic second-level domain names in the .РФ zone, at the time of verification, 251,524 (39%) have MX resource records. Records of this type point to the servers that process e-mail for domain names. At the same time, 6,065 (1%) delegated domain names in the .РФ zone have an MX record pointing to an email server announcing support for the SMTPUTF8 extension, which is required to work with internationalized email addresses (EAI).
In the .RU domain zone, out of 4,805,356 delegated second-level domain names, 2,412,645 (50%) have MX records. At the same time, MX records of 253,590 (5%) delegated domain names in the .RU zone point to email servers that announce support for SMTPUTF8, that is, the ability to work with EAI addresses.
The study touched not only data on resource records of domains, but also the software of mail servers that support SMTPUTF8. It turned out that in most cases, the mail servers that support SMTPUTF8 and are listed in the MX records of the studied domain names use proprietary Google software (in the .RU zone - 78.25%, in the .РФ zone - 54.92%), and also open source software - Postfix and Exim: for the .RU zone - 5.68% and 4.04%, respectively, and for the .РФ zone, the share of Exim is 18.85%, and Postfix - 9.99%.
The study also found that the majority of mail servers supporting the SMTPUTF8 extension belong to Google, while popular Russian mail servers such as Yandex, Beget, Timeweb, REG.RU and others do not yet announce support for the SMTPUTF8 extension.
You can read the full text of the study on our website in the "Publications" section.