RFC 2122 (rfc2122) - Page 2 of 11
VEMMI URL Specification
Alternative Format: Original Text Document
RFC 2122 VEMMI URL Specification March 1997
2) VEMMI URL scheme utility and operability:
- VEMMI service selection: A VEMMI multimedia server will listen on
its VEMMI well-known port for incoming connections. The server
could of course be engaged in many simultaneous connections, and
after a connection is established, the terminal must be able to
select the desired VEMMI application, as a same system may host
different VEMMI applications.
The best mechanism to fully describe the VEMMI service to activate
is the URL mechanism.
- Reporting user action to a remote server: The VEMMI protocol
establishes a continuous TCP/IP link between the terminal and the
server during the whole user session. During a session managing
VEMMI objects, the user actions are usually reported back to the
server using the VEMMI user data report mechanism that is an
integral part of the VEMMI protocol.
However, in some case, the URL mechanism may be required to send
back reports to a remote host. VEMMI is for example able to display
HTML documents within a multimedia display area in a VEMMI dialog
box. these HTML documents may be managed either by the VEMMI server
(acting as a proxy gateway) or directly by the client software that
will issue itself the HTTP requests on the network and browse
across documents on the Web as a standard Web browser (the link to
the VEMMI server is kept and used for interacting with other VEMMI
objects and components but the VEMMI server may not be informed of
the user navigation on the Web inside the multimedia area).
In such a case, the URL mechanism could also be used to report the
user actions and commands within a HTML document to be reported to
the VEMMI server or even another system.
- Extension of Web browsers: The VEMMI protocol is quite
complementary to HTTP/HTML used by Web browsers, and several
networks operators have decided to support jointly Web and VEMMI
(seen as complementary protocols). Thanks to the VEMMI URL, Web
browsers will be able to activate a VEMMI client software module to
start a VEMMI session to the requested service when the user
activate a vemmi URL included in the HTML document.
3) Description of the VEMMI scheme
The VEMMI URL scheme is used to designate multimedia interactive
services conforming to the VEMMI standard (ITU/T T.107 and ETS 300
709).
A VEMMI URL takes the form:
vemmi://:/;
=
Mavrakis, et. al. Standards Track