IAM in Service Catalog
A group name is a sequence of name components, by convention written left-to-right from highest-level to lowest-level naming authority. Name components are written separated by a delimiter character.
Character set: Name components are limited to lowercase letters \ [groups:a-z\], digits \ [groups:0-9\], dash ("-"), and period ("."). Wiki Markup
Delimiter: The delimiter between components is underscore ("_").