Hey all, So following with the Tech WG call earlier today, I branched a question on legacy technologies and their interactions with UASG. I don't think it's a secret that a *lot* of infrastructure on the Internet often runs on either old versions of modern programming languages, is entirely obsolete, or otherwise not the forefront for new developments. I want to open a broader discussion on how we should handle these types of cases; i.e., document ways to implement/store IDN/EAIs? For context, here's a few places where Unicode either wasn't supported at the time, or are just obsolete but still common. This isn't an exhaustive list, just an idea of the types of systems that I know are still around at least to some extent. == Mainframe Systems/EBCDIC == Mainframes aren't obsolete by any measure, but due to backwards compatibility, most of them don't even use ASCII as a standard encoding but the EBCDIC specification, such as z/OS. Often times these systems host databases and reporting software (Mainframe DB2, not to be confused with the more common DB2), and still have production code written in COBOL, RPG, and other programming languages that have moved on to greener pastures. While these systems may not necessarily be directly webfacing, storing user information and email addresses (as well as communication with SMTP servers) is common, as well as text based systems interacting with these in the form of terminal emulator/3270 entry systems. == Visual Basic 6/ASP (not .NET) === VB6 is (sadly) not dead, and I know a fair number of organizations which can't migrate to VB.NET. The basic String data type in VB6 does support Unicode due to its COM hertiage, but much of the VB6 ecosystem still runs on codepages and older technologies for internationalization support. That being said, having a COM object for EAI/IDNs is much more doable here than some other systems. == dBase == Still exists (http://www.dbase.com/), and even still supports the MS-DOS versions (last update 2018!). There's no public documentation that I can find in a brief glance that talks about Unicode support. Obviously I could find more, but this gives an operating system, programming language, and database where Unicode is either non-standard or non-existent but may be used with handling IDN or EAI storage. Michael