- From: Matt Hammond <matt.hammond@rd.bbc.co.uk>
- Date: Fri, 08 Apr 2011 16:58:31 +0100
- To: "Clarke Stevens" <C.Stevens@cablelabs.com>, "public-web-and-tv@w3.org" <public-web-and-tv@w3.org>, "Olivier Carmona" <ocarmona@awox.com>, "Russell Berkoff" <r.berkoff@sisa.samsung.com>, "Bob Lund" <B.Lund@cablelabs.com>
- Cc: "Giuseppe Pascale" <giuseppep@opera.com>
Hi Bob, Your latter example is what I had in mind: a device that is connected to the home network and receives off-air broadcasts, but does not serve or stream that content around the home network. Instead the device itself includes a display, or is connected directly to one using HDMI or similar. It is not clear to me if the A/V transport service (or whichever service is appropriate) facilitates remote control type functions such as changing channel or playing back a recording, as distinct from choosing content to stream to another device. regards Matt On Fri, 08 Apr 2011 15:30:58 +0100, Bob Lund <B.Lund@cablelabs.com> wrote: > Matt, > > See inline below. > > Bob > >> -----Original Message----- >> From: Matt Hammond [mailto:matt.hammond@rd.bbc.co.uk] >> Sent: Friday, April 08, 2011 3:03 AM >> To: Clarke Stevens; public-web-and-tv@w3.org; Olivier Carmona; Russell >> Berkoff; Bob Lund >> Cc: Giuseppe Pascale >> Subject: Re: [HOME_NETWORK_TF] Home Network Technologies >> >> We also see facilitating discovery of content on the home network from >> the browser to be important. There is also the issue of security and >> privacy - a user should be able to determine what devices, applications >> and web pages have permission to control another device and discover >> content. >> >> As a broadcaster we deliver to multiple platforms over which we have no >> direct control (terrestrial, cable and satellite transmission all >> operated by different companies/consortia). Our interest is closer to >> the scenario >> 2(b) that you outline. >> >> What is not clear to me is whether the DLNA/UPnP capabilities for >> discovering and playing content also work for a box that does not have >> the capability to serve or stream off-air broadcast content on the home >> network (for example, a TV with integrated tuner). > > I am not clear on the question. If you mean a device that is not > connected to the home network then UPnP does not address that. But, such > a device would seem to be out of scope of all home network APIs. If you > mean a device that is connected to the home network but does not have > the capability to serve or stream off-air broadcast content, then yes, > the device can host the content discovery, connection manager and A/V > transport services. A TV with an integrated tuner could serve off-air > broadcast content if it was also connected to the home network and had > the appropriate UPnP services. > > >> This is one of the >> reasons why we have an interest in a simplified abstraction that negates >> the need for a controlling device to concern itself with the source and >> delivery method of a piece of content (as well as its format, codecs, >> device profiles etc) >> >> There is also potential to enable a substantial accessibility win here >> too if UI can be independent of the device(s) it is controlling. >> >> When considering the Remote UI as mentioned here, perhaps there are at >> least 3 related strands to this? Discovery/security; remote control; >> device-served remote UI. >> >> regards >> >> >> >> Matt >> >> On Thu, 07 Apr 2011 20:14:19 +0100, Bob Lund <B.Lund@cablelabs.com> >> wrote: >> >> > To amplify on Clarke's point a bit, it's useful to break down the >> > broadcast/cloud UI into more specific scenarios: >> > 1) Broadcast content directly from the cloud, UI from the cloud >> > 2) Broadcast to a UPnP media server that proxies the content on the >> > home network via content directory service, remote UI from the cloud >> > >> > Scenario 1 is the web, nothing special needs to be introduced. >> > Scenario 2 is more of a DLNA/UPnP model. There are two ways the UI >> > served from the cloud can gain the links to refer to the media server >> > content: >> > a) A back channel from the media server hosting the CDS to the cloud >> > server constructing the UI page. If the service provider controls both >> > the media server software implementation and the cloud UI server this >> > back channel can be service provider specific. The cloud UI server >> > constructs UI that references the home network content. There are some >> > subtleties around how the media LAN side IP address is referenced in >> > the UI page but it's doable. >> > b) The UI page served by the cloud server to the home network device >> > contains JavaScript that uses the discovery API that is being proposed >> > to discover the CDS and the content therein. The UI page JavaScript >> > can provide whatever degree of integration is desired between the >> > local content discovered and the cloud content referenced on the UI >> page. >> > >> > Bob Lund >> > >> >> -----Original Message----- >> >> From: public-web-and-tv-request@w3.org [mailto:public-web-and-tv- >> >> request@w3.org] On Behalf Of Clarke Stevens >> >> Sent: Thursday, April 07, 2011 11:05 AM >> >> To: Matt Hammond; public-web-and-tv@w3.org; Olivier Carmona; Russell >> >> Berkoff >> >> Cc: Giuseppe Pascale >> >> Subject: RE: [HOME_NETWORK_TF] Home Network Technologies >> >> >> >> Matt, >> >> >> >> UPnP currently defines a way to discover remote user interfaces, but >> >> it is pretty generic. Here are the specs: >> >> >> >> http://upnp.org/specs/rui/remoteui/ >> >> >> >> In this group, we're hoping to make this a bit more concrete by using >> >> HTML browsers, CSS, JavaScript, and providing some APIs for >> >> discovering and using devices and services on the home network. The >> >> back channel to the cloud service would just be a URL. That's maybe a >> >> bit oversimplified as there are other issued related to a commercial >> >> service offering, but that's the basic idea. >> >> >> >> As for more information on DLNA CVP, here's an announcement: >> >> >> >> http://www.dlna.org/news/pr/view?item_key=e2c163bfab8076edc2b33eba829 >> >> 3e8 >> >> 2cd2f11e3e >> >> >> >> It looks like DLNA doesn't yet have CVP for sale from its web site >> >> but W3C could encourage them to provide some more information, >> >> timelines, etc. >> >> >> >> Hope this helps. >> >> >> >> Thanks, >> >> -Clarke >> >> >> >> -----Original Message----- >> >> From: Matt Hammond [mailto:matt.hammond@rd.bbc.co.uk] >> >> Sent: Thursday, April 07, 2011 8:11 AM >> >> To: public-web-and-tv@w3.org; Olivier Carmona; Russell Berkoff; >> >> Clarke Stevens >> >> Cc: Giuseppe Pascale >> >> Subject: Re: [HOME_NETWORK_TF] Home Network Technologies >> >> >> >> Hi Clarke, >> >> >> >> >> >> Could you explain how this model where a remote user interface is >> >> served from the cloud would work for broadcast services? Does it >> >> require some kind of back channel between the rendering device and >> the cloud service? >> >> >> >> I would also like to understand what services CVP enables. Are the >> >> guidelines publicly available anywhere? >> >> >> >> regards >> >> >> >> >> >> >> >> Matt >> >> >> >> >> >> On Thu, 07 Apr 2011 13:40:12 +0100, Clarke Stevens >> >> <C.Stevens@cablelabs.com> wrote: >> >> >> >> > I think some of the functionality you want is already defined in >> >> > DLNA/UPnP and the rest will be very soon. As I mentioned earlier, >> >> > the URL that points to the content does not need to be on the home >> >> network. >> >> > This allows for content that can be offered from service providers. >> >> > Similarly, a service provider could serve a remote user interface >> >> > from the cloud. Features such as volume change and mute are already >> >> > provided, so a "second screen" could get a user interface from a >> >> > service provider and point to content remotely served by that >> >> > service >> >> provider. >> >> > >> >> > >> >> > There is also a DLNA guideline called CVP specifically designed for >> >> > content service providers. The first version is available now but >> >> > is somewhat limited. The second version is in development and I >> >> > believe it provides the remainder of the services you are looking >> for. >> >> > >> >> > Thanks, >> >> > -Clarke >> >> > >> >> > -----Original Message----- >> >> > From: public-web-and-tv-request@w3.org >> >> > [mailto:public-web-and-tv-request@w3.org] On Behalf Of Matt Hammond >> >> > Sent: Thursday, April 07, 2011 2:52 AM >> >> > To: public-web-and-tv@w3.org; Olivier Carmona; Russell Berkoff >> >> > Cc: Giuseppe Pascale >> >> > Subject: Re: [HOME_NETWORK_TF] Home Network Technologies >> >> > >> >> > Hi Russell, >> >> > >> >> > Your description matches my understanding of DLNA/UPnP - which is >> >> > useful confirmation for me - many thanks! >> >> > >> >> > I agree that this model works well for streaming between home >> devices. >> >> > But it makes the assumption that all content is streamable between >> >> > home devices. A TV or set-top-box that can receive broadcast or IP >> >> > delivered TV or radio does not necessarily match this. In order to >> >> > be able to implement some of the second-screen scenarios presented >> >> > at the last workshop, I would hope that APIs for home networking >> >> > are also able to query and control TV functions such as changing >> >> > channel or retrieving broadcast programme metadata. >> >> > >> >> > This is why I am interested in APIs that can support both in (if >> >> > possible) a single simple unified way. The approach we took at the >> >> > BBC with our Universal Control (UC) API is one possible way to >> >> > achieve >> >> this. >> >> > >> >> > If a TV implementing UC API needed to be able to discover and >> >> > stream content on other devices in the home then it would almost >> >> > certainly use DLNA/UPnP or other similar technologies to do this, >> >> > but the client/controller device does not need to know the >> >> > difference. From the perspective of a client of the UC API >> >> > implementing TV, streamed content is discoverable and selectable >> >> > for playback in the same way as a television channel or programme >> would be. >> >> > >> >> > regards >> >> > >> >> > >> >> > >> >> > Matt >> >> > >> >> > On Thu, 07 Apr 2011 08:39:18 +0100, Russell Berkoff >> >> > <r.berkoff@sisa.samsung.com> wrote: >> >> > >> >> >> Hi Matt, >> >> >> >> >> >> >> >> >> Let me try to answer "frame" your question/observation and >> >> >> hopefully provide some brief answers: >> >> >> >> >> >> >> >> >> Q1: Does DLNA/UPnP distinguish between the description of content, >> >> i.e. >> >> >> metadata describing content (title, description, available media >> >> >> formats) and the device actually supplying the content? >> >> >> >> >> >> >> >> >> Q2: Does DLNA/UPnP allow metadata and content to reside on >> >> >> separate devices on the home network? >> >> >> >> >> >> >> >> >> Q3: Does DLNA/UPnP allow the remote commanding of playback >> devices? >> >> >> >> >> >> >> >> >> >> >> >> A1: Yes...DLNA/UPnP has a distinct metadata service >> >> >> (ContentDirectory Service). The metadata provided by this service >> >> >> can refer to content elsewhere on the home network. >> >> >> >> >> >> >> >> >> A2: Yes >> >> >> >> >> >> >> >> >> A3: Yes...UPnP/DLNA allows remote commanding of playback devices. >> >> >> A Digital Media Controller can obtain descriptive content metadata >> >> >> and tell a playback device to "pull" a piece of content from a >> >> >> distinct "content source" on the home network. >> >> >> >> >> >> >> >> >> The Digital Media Controller in this scenario would examine the >> >> >> metadata from both the Playback Device (Digital Media Renderer) >> >> >> and from the metadata service (Digital Media Server - >> >> >> ContentDirectory >> >> >> Service) and insure a media format is chosen that both the Content >> >> >> Source can provide and the Playback Device can render. Once a >> >> >> match is found the Digital Media Controller, would command the >> >> >> Playback device to fetch the content from the Content Source. >> >> >> >> >> >> >> >> >> Regards, >> >> >> >> >> >> Russell Berkoff >> >> >> >> >> >> Samsung Electronics >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> -----Original Message----- >> >> >> From: Matt Hammond [mailto:matt.hammond@rd.bbc.co.uk] >> >> >> Sent: Wednesday, April 06, 2011 5:03 AM >> >> >> To: public-web-and-tv@w3.org; Olivier Carmona >> >> >> Cc: Russell Berkoff; Giuseppe Pascale >> >> >> Subject: Re: [HOME_NETWORK_TF] Home Network Technologies >> >> >> >> >> >> >> >> >> Hi Olivier, >> >> >> >> >> >> >> >> >> On Wed, 06 Apr 2011 12:22:38 +0100, Olivier Carmona >> >> >> <ocarmona@awox.com> >> >> >> >> >> >> wrote: >> >> >> >> >> >> >> >> >>> >> >> >> >> >> >>> Hi Matt, >> >> >> >> >> >>> >> >> >> >> >> >>> DLNA 1.0 is about two-box pull model: on one side you have a >> >> >>> Digital >> >> >> >> >> >>> Media Player (a client in your description) and on the other side >> >> >>> you >> >> >> >> >> >>> have a Digital Media Server (a rendering device in your >> >> description). >> >> >> >> >> >>> DMP discovers and then browses DMS, and can request one of the >> >> >>> browsed >> >> >> >> >> >>> items to be played. The only difference with your model is that >> >> >>> this the >> >> >> >> >> >>> DMP that based on the information exposed by the DMS, decides >> >> >>> wherever >> >> >> >> >> >>> it can play the content. >> >> >> >> >> >> >> >> >> My explanation was not as clear as it should have been - please >> >> >> accept my >> >> >> >> >> >> apologies for that. The client that I described does not display >> >> >> media and >> >> >> >> >> >> does not send or receive media streams. It is the server that will >> >> >> >> >> >> render/display media, and it is up to the server to work out what >> >> >> media is >> >> >> >> >> >> available to it and to arrange to stream (or otherwise obtain) it. >> >> >> This >> >> >> >> >> >> aspect would be completely opaque to this client. The >> >> >> server/renderer >> >> >> >> >> >> could well use DLNA to discover and stream that content from a 3rd >> >> >> device, >> >> >> >> >> >> but the client would not be aware of this. >> >> >> >> >> >> >> >> >> For me, the attraction of this model is that it is more abstract >> >> >> that just >> >> >> >> >> >> streaming and can easily subsume access to local storage but also >> >> >> access >> >> >> >> >> >> to services such as live television broadcast. A television >> >> >> programme is >> >> >> >> >> >> just another item of content that the server reports it has >> >> >> available to >> >> >> >> >> >> it, and which the client can ask it to display. >> >> >> >> >> >> >> >> >> >> >> >> >> >> >> regards >> >> >> >> >> >> >> >> >> >> >> >> Matt >> >> >> >> >> > >> >> > >> >> >> >> >> >> -- >> >> | Matt Hammond >> >> | Research Engineer, BBC R&D, Centre House, London >> >> | http://www.bbc.co.uk/rd/ >> >> >> -- >> | Matt Hammond >> | Research Engineer, BBC R&D, Centre House, London >> | http://www.bbc.co.uk/rd/ -- | Matt Hammond | Research Engineer, BBC R&D, Centre House, London | http://www.bbc.co.uk/rd/
Received on Friday, 8 April 2011 15:59:24 UTC