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Cosmic Interactivity

Biswajit.HD

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There’s something new in the air and everyone is talking about it. Something that has true potential to change our idea of entertainment. What is it?

It all started off back in the day with black and white telecasting through radio waves. Doordarshan was the only thing we had on our television back then. Then we up scaled and moved on to color television and its numerous cosmetic changes. In time, cable TV network took over the Indian viewer by storm and it has been the mainstay of entertainment in our homes ever since. On a parallel level, we saw the Internet era creep in. In the past year, Internet has spread across the country at an organic pace with fast, reliable and affordable bandwidth. In recent months, you might have heard the new buzz word—IPTV. We spoke to some of the major players in this space to dig information whether this new technology could change the way you are entertained at home—in a brand new way!

If you believed the hype, and thought that IPTV is just another form of TV, you were wrong! IPTV technology can potentially signify a complete transition in the way you watch television. Tech Mahindra and Sun Microsystems have joined hands to enable the roll-out of cost-effective and efficient IPTV services in India and the Asia Pacific (APAC) region. Sun is also partnering with players like Digisoft, Envivio, Harmonic, I-Make, Verimatrix and Mototech.

We had the opportunity to interact with Mr. Shankar Allimatti, Vice President of Tech Mahindra (Next Generation Technologies) and know more about their alliance with Sun Microsystems and the IPTV project. We received some very valuable input from him about certain vital aspects that IPTV has to offer.

IPTV vs Cable TV
Picture yourself watching an advertisement on a normal cable TV network and you see this product you want to purchase. You might instantly pick up your phone and dial the number listed in the ad and place an order. With IPTV, you do not need to call anyone, simply shop through your TV. This is just one of the major distinguishing characteristics of IPTV. Apart from this, most operators bundle Video on Demand (VoD) with IPTV which is yet another fun and interactive arena to explore, where you can select to view some of the newest programming material—from TV serials to the latest blockbuster movies—at your own convenience! Other features like VoIP (Voice over Internet Protocol) and Broadband Internet connectivity is also an option.

How much does it cost?
In a price conscious market like ours, the cost of a commodity rules above any other factor while opting for services or products. Tech Mahindra sees IPTV as most suited for price-sensitive markets because a user pays only for channels that are opted for and not for the entire band of channels as is the case in cable TV. Apart from the customization factor, you can actively participate in most of the services offered.

Regarding the initial cost, the switch over from Cable TV to IPTV will be considerably low. For instance, price of a set top box should not exceed that of a DTH setup. This cost might also be subsidized by the service providers. Recurring costs will be dependent on the user’s preference, choice and number of services opted for.

Performance
On the technical front, the current compression standards, that is MPEG4 and H.264, and a decent 1 MBps satellite downlink should suffice for smooth IPTV services. However, currently these speeds are available only in metros and the bigger cities like Hyderabad, Pune and Bangalore.

Bandwidth: Allimatti mentioned that the bandwidth in the network core would be fairly independent of the number of subscribers and was typically dimensioned on the number of channels to be delivered. Quality of the video feeds might deteriorate if the service providers lack improvised access networks.

Buffering: IPTV buffers at the set top box level in milliseconds. Buffering might cause jitters in video feeds which means it might skip frames while streaming due to faulty IP packets or slow bandwidth. But these glitches can be alleviated if the service providers maintain the standards of the originally provided infrastructure. So clearly, the onus of this technology’s success lies with the ISPs and their ability to sustain the level of their infrastructure.

Cosmos to couch
Now that we know what is IPTV, let’s take a look at how IPTV content travels across the reaches of space, via satellites and over oceans to reach your living room.

The video signals are first downlinked from satellites by the telecom companies (for instance, MTNL). At times these telcos also encode them before relaying. Once the video streams are downloaded by a service provider, it gets into the ‘core’ of the telco network. The core is a huge network that handles different sorts of medium like data, video, voice etc. Here they are encoded into MPEG or H.264 video formats and then broken down into IP packets that are picked up by a range of service providers. Layers of functionality can be added to this stream, via VoIP services, VoD, and Internet access.

While watching a video online, you must have seen how the video stream is first ‘buffered’ to your computer before it starts playing. The IPTV set top box connects to the DSL line for collecting the data packets. It then buffers them, puts them together into one single video stream and finally decodes them for display. Telecom companies have complete control from top to toe in the process of IPTV which ensures consistent delivery of good quality transmission to the end user. These video streams are then multicasted to the service providers (we know them as cable operators) and all channels are broadcasted simultaneously to them. They are then relayed signal by signal to the subscribers as opposed to an array like in cable TV. Sun Microsystems and Tech Mahindra are jointly investing in a Next-Gen Lab setup to showcase a pre-integrated end-to-end IPTV system for tier 1, tier 2, and tier 3 service providers. The IPTV lab will feature solutions from a group of partners and Sun’s own Streaming System.

One by One
When connected to our normal cable TV provider, we are able to tune into channels which become presets into our TV sets. This is because the signals received from the cable operator carry all the channels that the subscriber opts for. However, in the case of IPTV, there is only one signal that reaches the subscriber’s set-top box which carries one channel at a time. All the channels are grouped at the service provider’s end and every channel belongs to a specific subset of channels. A technology called the IP group membership protocol allows the subscriber to switch between channels via the set-top box. When switching between channels, the set top box sends a request to the service provider; the request is then checked to ensure authenticity of the subscriber to use that particular channel. Once verified, the user is then added to that particular group and the relevant channel is streamed to their set top box.

While receiving single streams/channels (unicast), the quality controls seem to suffice most of the times. But when it comes to multicast/multiple ones, it is important to have measures that maintain quality. The Forward Error Connection method (FEC) takes care of this aspect. Here, the server sends multiple or surplus streams so that there is no fragmentation or errors in playback in the event of some packets getting lost.

Future of IPTV in India
Tech Mahindra estimates that there are approximately 75 million households having televisions, out of which only about 25-26 million use cable TV services and the rest stick to national television. These many million viewers are catered to by the local cable providers who are now partnering with giants such as the Hindujas. The satellite TV (DTH) services that have been in existence for some years now, account for only about a million households—the major providers in this space being DD Direct, Tata Sky and Dish TV.

Tech Mahindra is involved in developing interactive applications like video blogging, video mails, news and stock tickers. The proof of concepts of these applications already exist in their IPTV laboratories. Looking at the current market scenario, things certainly seem to be looking up.

If all goes well this year, we should have high definition interactive video feeds coming into our homes through DSL lines. Get ready—your telly is about to exp

Source : Chip magazine.
 
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