Registration/Login is famous part in Web Based Application to enable User Privacy and track their records and Changes made.This is Easy in PHP -where i have written already Three post regarding login...
https connection was thought as More secured but After Heart Bleed.Probably http is more secure :p .And Recently you would heard that Google Prefers HTTPS connection for SEO boost up and Higher ranks...
Creating RESTful WebService Doesn't matters here.It matters about how you Provide Documentation for your Users/Developers to consume your web service in Rightful manner.You Need to Create Your Best out...