Skip to main content

How can an Xlet application be deployed to the TV receivers independently?

3 replies [Last post]
Joined: 2007-07-19

Hi everyone,

I've read several chapters of and . But for the reason that my home only have a Zapper, a digital receiver that has only channel-changing capabilities, so I have no ideas how an Xlet could be deployed to the receiver independently.

Is that possible? Could Xlets be deployed by the ISVs other than the Video/Audio content providers? Are the users have a chance to lauch an Xlet application whenever they want?

If all the answers are positive, the Xlet will be a very promising technology. I hope anyone who has a mhp-enabled or ocap-enabled tv receiver could share some experience with me, thank you.


David Song

Reply viewing options

Select your preferred way to display the comments and click "Save settings" to activate your changes.
Bill Foote wrote:

> Is that possible? Could Xlets be deployed by the ISVs other than the Video/Audio content providers? Are the users have a chance to lauch an Xlet application whenever they want?

Hi David,

Well... Yes and no. Yes, you can deploy an xlet to a
receiver, but how "independently" you can do this is
perhaps a matter of perspective. Independently of whom?

So, take Blu-ray. The model here is "the disc owns the box."
Thus, the person who creates the disc gets to control what
applications run, and what applications don't run. The security
model of BD-J backs this up. This intentionally prevents a third
party from "installing" an xlet on a player, and having it take
control of the presentation of content owned by someone else.

Of course, a player might have other apps somewhere on the same
screen. For example, if you're watching a disc on a PC and the
software player isn't full screen, you can have other stuff going
on in the same screen. This doesn't really count as running
an xlet in any way meaningfully linked to the disc content, though;
it's just stating the obvious, that modern computers have window
systems and can multitask.

On a cable network, the situation is kind of similar. In OCAP,
the basic rule is "the MSO owns the box" - whether the receiver
be a STB that the cable operator actually owns, or be it a consumer-
owned device using a cablecard, the MSO manages what applications run.
They, in turn, have contractual obligations that govern what can
go on top of, say, a movie - you can't, for example, expect that
the content owners will let an MSO make an MST3K application that
mocks Waterworld, for example. Not that there's any reason to
mock Kevin Costner in his role as "Mariner," mind you. BTW, if
you're not familiar with the term MSO, it's a fancy synonym for
"Cable TV company" - it stands for "Multiple Service Operator," IIRC.
And, oh yeah, the consumer-facing brand for OCAP is "Tru2way"
these days.

So, generally speaking, you can't "install" an app on any of these
boxes, and then run it on top of content you don't own. This isn't
due to a technical limitation; rather, it's due to a security model
that was intentionally put in place to protect the rights owners.

Of course, if you have content yourself, and you want to let people
put applications on top of your content, there are zillions of ways
you can enable that in Blu-ray, and if you care to negotiate carriage
with IPTV or cable service operators, you could duplicate the experience
over there.



To unsubscribe, e-mail:
For additional commands, e-mail:

Joined: 2007-07-19

Hi Bill,

So the TV receiver's Xlet Runtime environment isn't an open programming platform. It's no wonder that I couldn't find any valuable information in some specifications. Thank you for sharing Bill, it's very helpful.


David Song

Joined: 2010-12-06


I'm an italian Master Degree student and i'm doing my thesis with DTV. I developed a Java Xlet and tested with the xleTView emulator and now I want to test it in a real STB but I have a little problem:

I don't know which STB I have to buy, do you have any idea? and how can I put my xlet in the STB?

Thanks in advance.