Romeo can query his server for the availability of "User Invitation" and + "Account Creation" commands:
TODO: use appropriate node namespace.
When performing the account creation, Juliet's client needs to ensure + that the server supports the extended IBR protocol with a <preauth> + token: TODO
OPTIONAL.
A user can execute the 'invite' command to obtain a new invitation link + with a unique invitation token.
The token should be unique, sufficiently + long and generated by a strong random number generator.
A server MUST provide the uri field which contains an XMPP URI of the following format:
xmpp:inviter@example.com?roster;preauth=TOKEN;ibr=true
The ibr query component in the XMPP URI indicates that - the invitee is allowed to create an account on the Romeo's server. + the invitee is allowed to create an account on Romeo's server, using the + 'preauth' token. If the server does not support or allow in-band registration for invited users, the server MUST omit the ibr query component.
Additionally, the server SHOULD provide the landing-url field which contains an HTTPS URL of a web-based landing page as described in &xep0379; ยง 3.3. The URL format may differ from the example shown here depending on where the landing page is hosted.
+If the server omits the landing-page field, Romeo's + client SHOULD generate an appropriate landing page URL hosted by the + client developer or a trusted third party.
A server MAY provide a field which provides the expiration date of the generated token. The expiration date MUST conform to the DateTime profile specified in &xep0082;. If the field is not provided, the token does not expire.
+Romeo's client should provide adequate means to export the + landing-page URL, possibly accompanied with a short + description and the expire information, so that Romeo can + share it with Juliet by other means than XMPP, like e-mail or a QR code.
+