RFC 5724 (SMS URIs)

in august i declared the sms URI scheme finished and that was a bit optimistic (one more iteration was required)... but now it really is finished and published and registered and everything! it has been published as RFC 5724 (here are ASCII and HTML versions), and here's the abstract:

This memo specifies the Uniform Resource Identifier (URI) scheme "sms" for specifying one or more recipients for an SMS message. SMS messages are two-way paging messages that can be sent from and received by a mobile phone or a suitably equipped networked device.

the idea is very similar to the tel URI scheme that identifies an endpoint through a phone number that is reachable by voice call. for the sms URI scheme, the identification method is the same (a phone number), but the interaction is different (send an SMS message). when using such a URI in a link, browsers on mobile devices could simply switch to their built-in messaging applications. regular browsers (i.e. those on computers where no built-in phone service is available) could be smart and switch to an SMS messaging application configured by the user, which could be either an external app, or a web-based service.

now let's hope that all the wonderful mobile platforms out there (iPhone, Android, Symbian/S60, WebOS, Windows Mobile, BlackBerry OS, BREW, JavaME/JavaFX, Flash Light; did i forget any?) will start supporting this new URI scheme. and of course there's the usual chicken-and-egg problem of why support the scheme if there is no content using sms URIs and why start using sms URIs if they are not supported by most clients. only time will tell whether sms URIs will become widely used; for the tel URI scheme, adoption has been a bit on the slow side, but there definitely is some uptake by users as well as by clients.

implementation in most cases should not be hard, because it is mostly about dispatching, and not about implementing the actual functionality. firefox 3's web-based protocol handlers, for example, should make that rather simple, so that services offering web-based SMS could support their customers to be able to easily use sms URIs when they encounter them. other browsers might not be quite as ready for simply handling a new URI scheme, but even then any decent browser should have some well-structured URI scheme dispatching that should make it rather easy to add new scheme handlers.