IBC Connected Home: it looks like a hybrid future
Connected home technologies have struggled to keep pace with expanding ambitions among operators and broadcasters, but that may have changed, judging by various announcements at IBC2011.
The home network initially evolved across two parallel but initially separate movements, one extending Pay TV services to multiple TV sets around the house and the other enabling sharing of multimedia content including photos and user generated videos among consumer devices such as cameras and PCs. Now these two parallel lines are converging around the concept of the complete digital home, incorporating diverse electronic devices such as heating control systems and even refrigerators as well as TVs. This is taking Pay TV operators into new territory and bringing them up against emerging over-the-top (OTT) providers in a key battle zone.
At the same time, operators have been hampered until recently because they lacked some critical technology components, particularly relating to Quality of Experience (QoE) and security, which are needed not only to satisfy consumers but also meet the requirements of content owners.
The tablet boom, meanwhile, has increased demand for home content delivery but also emphasised the QoE problem by making it necessary to delivery premium video over Wi-Fi, since these are not wired devices. It means that, like it or not, the physical home network cannot be built purely from one of the wired technologies like MoCA (Multimedia Over Coax Alliance) for coaxial cable, the Home Plug Powerline Alliance for electrical cables, Ethernet over Category 5 or Home PNA over standard telephone cables. It means that one of the wired standards could provide either the backbone or backup for Wi-Fi, given that the latter still cannot guarantee high quality video delivery across a whole home without an access point in almost every room.
Momentum behind MoCA standard
The key recent development here is the hybrid set-top box or media gateway supporting both Wi-Fi and one or more of the wired interfaces, so that content can be delivered to TVs and tablet devices. At IBC2011, Dutch cable operator UPC announced that it would be providing such a solution using a media gateway developed by Samsung in conjunction with client boxes for other rooms around the house, all connected to coaxial cable via MoCA. Video is then delivered to wired devices over MoCA and wireless ones over Wi-Fi.
“Our MoCA chips go into the home media gateway box UPC purchases from Samsung, as well as the companion client boxes,” says Patrick Henry, President and CEO of MoCA chip maker Entropic Communications. “Samsung did the integration, with a different company providing the Wi-Fi chips.”
The question for other operators is which of the wired technologies they should deploy for the backbone, given that Wi-Fi is almost the only option for the wireless network, unless other contenders such as femtocells gain ground. In the U.S. MoCA is the overwhelming favourite, since most homes there have several coaxial cable outlets and coax is already a well proven medium for carrying high quality video.
Elsewhere, including in much of Europe, MoCA’s prospects had until recently been largely dismissed because of the obvious reluctance by operators or home owners to install new cabling when they can get by with whatever is there already. This sentiment provided the motivation for Powerline in particular, which is now being deployed by some European operators, but which cannot yet match the consistent performance of MoCA as it is subject to varying qualities and types of power cabling.
Furthermore, as Henry pointed out, MoCA is more prevalent than was thought in Europe, with a recent survey by IHS Screen Digest finding that of the 30% of European homes with a cable TV service, many had as many as three coaxial outlets. Henry also pointed out that satellite TV customers tend to have coax already installed, since this is the physical medium connecting the receiving dish to the set-top box.
According to Henry, availability of the latest MoCA 2.0 standard, demonstrated for the first time publicly at IBC, is creating momentum behind the standard, more than doubling throughput speeds compared to MoCA 1.0, from 175 Mbps to 400 Mbps. Henry suggested that MoCA would be implemented in most European homes served by cable or satellite operators but he agreed that Powerline would play its part for some IPTV and OTT providers.
Broadcom supports hybrid approach with Wi-Fi/Powerline processor
However, another key chip maker, Broadcom, is betting on Powerline being more than a bit part player in the future connected home. It has just announced what it claims to be the industry’s first single chip Powerline package, incorporating the algorithms needed to overcome interference from the unpredictable electrical sources sharing the same wires. This will reduce the cost for vendors of building plug-and-play connected home gateways and set-top boxes. Broadcom has also just announced a dual processor combining Wi-Fi and Powerline, which is likely to become a popular combination in Europe, even for some cable and satellite operators.
Such hybrid approaches will gain ground among operators, according to Broadcom’s Technical Director for Broadband Communications, Stephen Palm. “Within the home, a blend of wired and wireless network links can be deployed so that when one interface fails or degrades, another will still be active,” says Palm. “For example, when Wi-Fi coverage is interrupted, PLC [Powerline] can pick up the load. Further, Wi-Fi and PLC channels can be aggregated, extending the range for which a given required throughput level is achievable into areas where both Wi-Fi and PLC signals are individually relatively weak. Delivering as close as possible to 100% coverage in this way enables service quality and continuous operation. It also reduces expensive service calls to a minimum.”
Broadcom is also making a strong play for cable operators, in particular through its Full Band Capture technology, demonstrated at IBC, in which a single chip in a gateway or set-top box digitizes the entire 1 GHz downstream cable spectrum. This tackles the problem of proliferating cable tuners caused by homes watching multiple channels on different devices. Tuning is performed in the chip, which means it occurs almost instantaneously, enabling faster channel change for consumers. At present channel change can take two seconds or more on digital cable services, because of the delay while tuners retune to a different frequency before they can start demodulating the data.
“We see today’s tuning architecture as restrictive for future connected home applications because of cost, complexity and power issues,” says Broadcom’s Senior Manager of Cable Set-Top Box Technology, Brett Tischler. “Full-Band Capture shrinks the cost and power needed to bring additional video streams and IP services into the home by reducing the number of connections and discrete tuners.”
In fact, Broadcom believes that energy considerations will play a part in determining the architecture of home networks, encouraging a client/server approach with most of the power concentrated in the latter. “We see reducing energy costs in the home as a major benefit for users,” says Tischler. “The server/client set-top box architecture in the home reduces power while still enabling STB sharing.”
DTCP-IP supports premium video over DLNA
As well as saving energy, minimising the amount of processing required within the increasing population of home client devices will keep costs down and prevent connection to TV services being a barrier to entry for CE (Consumer Electronics) vendors. The objective of avoiding unnecessary processing in the client is also determining the course of content security in the connected home, leading to a significant announcement at IBC by DLNA (Digital Living Network Alliance).
DLNA is the “standard of standards” for the home network, incorporating protocols, interfaces and software components from other bodies to create a universal platform for interoperability and automatic discovery among connected devices. But a considerable function was missing until recently from the DLNA platform: support for premium content distribution within the home. This required a decision over the associated security, given the need to protect against piracy or unauthorised redistribution. At IBC, DLNA plugged this gap by announcing its support for premium content using DTCP-IP (Digital Transmission Content Protection over IP) for secure transmission across the home network.
DTCP (and its extension to IP) was developed by the so called 5C consortium comprising chip maker Intel along with four major CE companies: Hitachi, Panasonic, Sony, and Toshiba. The choice was fairly inevitable given the decision firstly by 5C, and later echoed by nearly all members of DLNA, that security for client home devices must implemented just in software in order to keep down costs and avoid barriers to entry to the connected home for CE makers.
The gateway or set-top box will usually employ hardware protection of some form to support the DRM and associated CA mechanism. The role of DLNA is then to ensure that these rights are maintained and enforced across the home network via the DTCP-IP software. “Whatever DRM is chosen, if that DRM is also on the server on which the content resides and the player recognises the DRM, then both player and server recognise each other and ensure that the content rights are honoured according to those DRM rights,” explains Nidhish Parikh, Chairman and President of DLNA. “DLNA then makes sure this link is protected. It is about link protection rather than content protection.”
DTCP-IP employs some new techniques to reduce the risk of content being transmitted either deliberately or inadvertently to a device outside the home authorised to receive it, which is essential for winning the confidence of major rights holders. One of the techniques involves measuring the time taken to transmit an IP packet between the source and destination before allowing video to be transmitted, to help prevent physically distant devices from accessing the content.
Still debate about cloud versus client/server architecture
There does seem to be some consensus emerging in the connected home around DLNA and around hybrid networks combining Wi-Fi with one of the wired options. The remaining uncertainty concerns the architecture and whether cloud based or client/server approaches prevail. To some extent this depends on who wins the battle for the connected home, with traditional operators favouring client/server but some content owners and also smart TV makers looking to bypass the fat gateway and deliver straight to the end device.
By Philip Hunter
Philip Hunter is a technology journalist specializing in the business and delivery of video and digital entertainment.
Philip Hunter is a technology journalist specializing in the business and delivery of video and digital entertainment.
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