VoD creates a major bandwidth challenge
A growing consumer appetite for VoD services will overwhelm the residential broadband networks many service providers use today. These networks were designed to deliver basic Internet connectivity or traditional broadcast TV services. They often lack the three capabilities — scale, performance and flexibility — needed to deliver the video content people want, when and where they want it.
The on-demand aspect of VoD is the major problem for today’s residential broadband networks. With traditional broadcast services, video servers send a single content stream into the network. As the content gets closer to the user, the network creates more copies so that every end user can receive one. With VoD services, the video server must send a separate video stream to each end user that requests a video. All of these video streams combine to create an explosion in bandwidth in the IP services network. The closer you get to the video server, the more capacity is required (Figure 1).
Compared to traditional broadcast TV services, a single 2 GB movie delivered on demand to 100 customers requires:
- 2 times the bandwidth at the aggregation layer
- 20 times the bandwidth at the IP services edge
- 100 times the bandwidth at the video server layer
VoD consumption will grow rapidly
According to a recent Alcatel-Lucent Bell Labs study the VoD bandwidth challenge will hit networks sooner than many service providers might realize. The same study reports that U.S. subscribers will spend considerably more time watching video by 2020 and their viewing habits will change as well. Users will spend less time watching broadcast TV as over-the-top (OTT) and on-demand video consumption increase (Figure 2).
Demand for VoD services will grow as consumers demand more freedom of choice from their service provider. Specifically, they are asking for:
- Device freedom: The ability to consume, control and share content on any device — from PCs to gaming consoles, tablets and big-screen TVs.
- Schedule freedom: The ability to choose live TV, time-shifted TV or VoD.
- Location freedom: The ability to enjoy the “home” quality of experience (QoE) at public Wi-Fi® hotspots.
- Content freedom: The ability to watch any content type — cloud, premium, live or user-generated — at the resolution of their choice.
- Interactive freedom: The ability to integrate sidebar content, social media apps and interactive ads into the experience.
- Plan freedom: The ability to make tradeoffs between bandwidth usage and costs.
While the numbers will vary for service providers in different parts of the world, the demand trends are universal; they will affect service providers everywhere. According to the Bell Labs study, peoples’ desire for free-form video consumption will mean a 28 percent compound annual growth rate (CAGR) in demand for managed VoD content delivered as part of an IPTV service (see left side of Figure 3). Consumption of OTT video content will speed up even faster, with U.S. consumers reaching the zettabyte (ZB) era of video consumption in just 8 years (see right side of Figure 3).
Challenges escalate with VoD growth
Naturally as people consume more VoD, network traffic will also increase. It seems reasonable to assume that video traffic in the network will grow at the same rate as the average traffic from subscribers’ households. However, because users are switching from traditional broadcast services which use multicast, to VoD services which use unicast, this is not what is going to happen. According to Bell Labs, by 2017 traffic in U.S. IPTV triple play provider networks will increase 2.5 times faster than the average traffic flowing into households at the peak hour of 8:00 p.m. (Figure 4).
As VoD traffic increases, so will the challenges for service providers that are still using today’s residential broadband network architectures.
- Old technologies will limit evolution:
- Broadband Remote Access Server (BRAS) routers will become obsolete. They simply won’t have the capacity to handle the increased traffic or the features to support personalized video and Internet services.
- Costs will increase:
- Service providers will have to invest a lot more in network transport and peering resources to deal with the massive bandwidth spikes that will occur in the network.
- These costs will escalate even higher for service providers that operate and maintain two networks today — a network that delivers video services and a network that delivers high-speed Internet (HSI) services.
- Service experience will deteriorate:
- Traffic from unicast VoD streaming will congest networks and video servers. This means service availability and quality will decrease.
- Operating separate networks for video and HSI will make it difficult for service providers to deliver the blended service experience their customers are asking for.
The video edge
With the expected VoD traffic growth and its associated challenges, today’s network architectures may no longer make business or technical sense. They will quickly become too expensive, inefficient and ineffective. To thrive in the VoD era, service providers need a network that:
- Delivers compelling new VoD services at the lowest cost per bit
- Helps them control escalating OTT traffic costs while delivering the freedom subscribers want
A next-generation broadband IP network based on a high-capacity Broadband Network Gateway (BNG) and Content Delivery Network (CDN) caches delivers the capabilities service providers need in the VoD era. This single network architecture distributes the IP edge and content injection from central locations all the way to the edge of the aggregation layer. This approach:
- Handles surging video traffic by bringing terabit speeds to the IP edge
- Reduces bandwidth requirements and increases service quality and reliability by moving content injection closer to customers
- Reduces operating costs and supports delivery of any service to any device by converging managed video and Internet service delivery networks
- Enables delivery of flexible and personalized VoD services by bringing service intelligence to the IP edge
- Enables uninterrupted user and device growth by supporting IPv4 continuity and migration to IPv6
Stay tuned for our next article How to Take Your IP Edge into the Video Era for details on how you can prepare for the video challenges discussed in this document. To contact the author or request additional information, please send an e-mail to email@example.com.