Universal Acceptance (UA) is a term coined by Ram Mohan to represent the principle that every top-level domain (TLD) should function within all applications regardless of script, number of characters, or how new it is.[1]
Historically, there were a limited number of TLDs available in strings of two or three Latin-script characters. This began to change in 2000, when ICANN introduced new generic top-level domains (gTLDs) that were longer than three characters, such as .info and .museum. ICANN began to address these issues through initiatives such as creating a Universal Acceptance Toolkit[2] in 2006, which provided reference code to software developers on how to cater for all TLDs correctly.
In 2010, the first internationalised domain names (IDNs), or domain names using non-Latin characters, were introduced. In 2013, ICANN's New gTLD Program introduced over 1,000 new gTLDs to its root.[3] This expansion of the Domain Name System’s Root Zone further exacerbated challenges associated with universal acceptance of these domain names. For the principles of Universal Acceptance to be realized, all valid domain names and email addresses must be accepted, validated, stored, processed and displayed correctly and consistently by all Internet-enabled applications, devices and systems.[4]