How can operators best manage and monetise the capacity demands of Internet TV? Jonathon Gordon takes a look
There has been much controversy over who should foot the bill for over-the-top Internet TV services such as the BBC iPlayer, ITV's catch-up TV and Channel 4oD, as well as non-broadcaster user-generated content channels such as YouTube and Joost. The rise in popularity of these bandwidth-intensive services seems to know no bounds. According to Ofcom online viewing has doubled over the past year from 1.57 million to 2.96 million, with one in nine UK homes, for instance, now tuning in via their PC. Our viewing habits are changing and we now demand that footage be available to view, perhaps repeatedly, anytime, anywhere. This trend is even seeing PVRs (personal video recorders) and home media centres equipped with Internet connectivity. In such numbers video services consume vast amounts of broadband capacity. So much so that there is a real danger of their popularity threatening the deployment of next generation networks.
Why? Because the way these services are monetised means there is little payback for the operator. Research from Telco 2.0 looking at the impact of the BBC's iPlayer on UK ISP Plusnet found that costs have gone up 200 per cent, from 6.1p to 18.3p per user, because the ISP needs to buy more capacity but is seeing no additional revenue. And it's not just the operator who gets the short end of the straw. Users are also being short changed given that three hours viewing of Joost, a P2P video service devised by the same founders as Skype, would use up the 1GB monthly allowance awarded to most subscribers. Content providers too have a vested interest in how this content is delivered. Poor delivery means their service may alienate viewers. Internet TV content is highly susceptible to latency, delay and jitter caused by fluctuating contention rates and the emergence of high definition footage, which can consume up to 75Mb per minute when streaming at 10Mbps, is likely to further exacerbate the problem.
So should the service provider, content provider or end user foot the bill? At the moment, the jury is out on what new business models will emerge. Traditionally, a linear model has seen consumers pay for access to content and distributors paying the content provider with additional revenue generated from advertising. The operator is left out of the equation based on the assumption that the fee users pay for their broadband connection will cover consumption. In reality there is little correlation between content and the cost of delivery. iTunes, for example, charges a dollar per MP3 download and around five dollars for a movie even though the latter is 100 times greater in size. Clearly operators can't charge a corresponding amount for Internet video yet at the other extreme, user-generated content is available for free. There has to be a middle ground.
Internet TV consumption monopolises resources and should the current situation continue unabated some argue that the operator will be unable to cope with operational expenditure ruling out network upgrades and stymying technological advancement. New business models, therefore, have to emerge. Perhaps the ISP will partner with legitimate content providers, or they may decide to steer clear of any content-related activity altogether, choosing to act as an access-only conduit but with payment reflecting the level of access. Regardless of the model that evolves, there is an imperative for the content chain and access provider to work more closely together to ensure Quality of Experience (QoE) for the user.
Content owners use Content Delivery Networks (CDNs), which sometimes use P2P file sharing technologies, to distribute content. P2P is valuable in improving QoE because this distributed storage and retrieval mechanism improves speed, minimises the load on servers and is a cheap and scalable means of distribution. These systems can be used to help operators prevent congestion. In return, the operator can assist the content owner by using caching technology to prevent service degradation.
Caching provides an ideal opportunity for the operator to add value. It works by storing popular content in close proximity to the user, allowing the operator to ensure content is delivered effectively while also meeting the needs of many users at once. But caching should only be seen as part of the solution because it tends to focus on specific traffic types rather than addressing traffic volume as a whole. What's more, as more content is made available, viewing is likely to fragment, making it more difficult to store the most popular content on the cache and improve the QoE.
The operator needs to be able to factor in off-net issues and the total bandwidth available, requiring caching to be supplemented by another technology capable of traffic management. Deep Packet Inspection (DPI) service optimisation is the ideal partner as this technology is capable of peering into the traffic stream to determine the signature of applications whilst also monitoring bandwidth consumption. It's a versatile technology as the operator can use it to passively monitor the network and capacity consumption or to take more assertive action. For instance, the operator could decide to prioritise video applications across the network, allowing the operator to guarantee Quality of Service (QoS) on this type of traffic. It's easy to see that this type of guaranteed service would appeal to Internet viewers allowing the operator to market this service or simply use it as a differentiator.
Network operators who favour the proactive approach can use DPI to establish network congestion policies. These allocate bandwidth according to the traffic category, either boosting or limiting the capacity. Traffic can be prioritised according to its content and congestion managed according to these categories. As a consequence, the operator can better utilise network resources, conserving bandwidth and postponing the need for frequent network upgrades. If the DPI device is subscriber aware, it can take into account any subscriber SLAs and compare these with the application categories dictated in the traffic management policy. DPI devices, which are both content and subscriber aware, can inform the creation of tiered service packages and be used to tweak these should usage patterns alter.
When used in league with caching, DPI traffic management can prioritise the passage of specified traffic across the network, reducing the delays associated with multimedia content buffering. When the subscriber requests content this communication is recognised by a blade housed on the DPI device in real time and the request is redirected to the caching engine. If the content is already housed on the cache, it is streamed directly to the subscriber from the caching via the DPI device. Alternatively, the cache can retrieve the content over the Internet, whether it is housed on CDN servers or P2P nodes, a request again routed through the DPI device. Regardless of the source, all content is managed by the DPI traffic management system to prevent congestion. DPI is also capable of prioritising this traffic and, if used with a service gateway functionality, can also subject it to filtering. The Service Gateway essentially allows the DPI device to interface with value added systems that provide security control or url filtering in order to carry out different rule sets. A Service Gateway DPI device unifies the operator's billing, subscriber management and provisioning systems, acting as a central point of management and one-stop shop that combines data to assess service utilisation. In an Internet TV context, it can carry out pre-processing or post-processing of the content flow, allowing it to perform harmful content filtering, for example.
As well as governing the network, a DPI traffic management solution can also be used as a customer-facing tool. It is able to set quotas for individual subscribers without showing a bias towards any one particular content provider. Quota Management can be used to differentiate between video traffic, VoIP traffic and web traffic, using volume usage quotas to provision and enforce customised service plans. The DPI device collects information and allocates usage per subscriber, meters actual service consumption, and adjusts QoS according to content, volume and time elapsed, or any combination of these parameters. When the allocated quota is reached, the operator can choose to redirect the customer to a portal where they can "refuel" their quota or change their service plan. Quota Management ensure the user's access to high quality content is protected and allows the operator to manage bandwidth resources.
In essence, DPI traffic management finally makes the operator part of the Internet TV value chain. A unified, open platform DPI traffic management device with Service Gateway and video caching capabilities optimises network resources and prioritises traffic according to the nature of the content. As a consequence, Internet TV traffic is retrieved and delivered in as timely and conservatively a way as possible while also allowing new subscriber-led service plans to be developed.
For the viewer, timing is everything. Uninterrupted access will become as necessary to the survival and proliferation of Internet TV as always-on broadband has been to the web. So operators need to turn on, tune-in or drop out.
Jonathon Gordon is Director of Marketing, Allot Communications, and can be contacted via