New-age CDN: Optimising the streaming experience and securing content delivery

By Shaun Lim

They say numbers do not lie. Where content consumption is concerned, almost half of viewers (44%) say they watch less TV because of live streaming, while Market Research Future estimates the global live streaming market to reach over US$247 billion in 2027.

To cope with this surging demand, content distribution networks (CDNs) have become essential to deliver the smooth and high-quality playback expected of live streaming. However, the current architecture of many legacy CDN platforms has profound limitations, said Zeck Lim, Regional VP, Content Provider, APAC, Qwilt.

He told APB+, “The most pressing issue is that CDNs still generate an individual stream for each viewer that typically originate from outside the communication service provider’s (CSP) network. These duplicate live streams consume significant bandwidth as they pass from the CDNs point-of-presence (PoP) through a peering point, across the CSP’s core network and, finally, over the last mile to each viewer’s home or mobile device.  

“This method works but is incredibly inefficient in terms of bandwidth utilisation. For massive live events, there may easily be millions of redundant streams crossing the service provider’s network and consuming precious capacity in the network core.”

Referencing a 2023 study by Muvi, Lim pointed out that with APAC demand for over-the-top (OTT) streaming surging at a CAGR of 10.75% between 2023 to 2027, CSP core networks are likely to become highly congested. Exacerbated by a growing demand for 4K/Ultra HD (UHD) content, the legacy CDN model will not be fit for the purpose, leading to a degraded consumer experience, he cautioned.

Suggesting how the progressive replacement of traditional broadcast by OTT is “inexorable”, Damien Sterkers, Video Solutions Marketing Director, Broadpeak, described how streaming technology uses individual connections between the network and users to provide a richer and more individualised experience. 

He was, however, quick to add, “This does also present a challenge in terms of scalability, especially during live events when large volumes of people are consuming content at the same time.

“CDNs are crucial to securing enough network capacity, but, given the exponential growth of traffic, they will have to dramatically improve their efficiency in the future. 

“The development of structural CDN optimisations — such as multicast-ABR, context-aware processes or cloud infrastructure — will help ensure a smooth and complete transition to OTT, without any network congestion or service quality issues. They can achieve a lower latency and generalise UHD on premium content, thereby improving user experience.”

Many major content distributors, he added, are already implementing multi-CDN strategies to improve their capacity, footprint, and service quality. To include high-performing CDNs, one approach that is currently being developed is to use local ISP services.

“By physically connecting the end users, ISPs have a more distributed infrastructure, meaning they can stream from much closer and use specific optimisations — thus providing more capacity and securing end-to-end quality,” Sterkers explained.

To judge the maturity and efficiency of a multi-CDN solution, he recommended the consideration of three main aspects: the criteria it uses for its selection, its level of granularity, and its dynamicity.

“Ideally, the solution considers both central rules — technical and business — as well as local dynamic metrics for each particular user, typically based on network awareness, network performance measures, or information from the player.

“It can then use this information to assess in real-time the best CDN option and automatically apply this choice ‘in-stream’, or, in a seamless manner and on a per-user basis,” Sterkers said.

To maintain the high quality of the user experience, Qwilt’s Lim suggested embedding the CDN inside the CSP network to be as close as possible to consumers.

Open Edge Caching pioneers such as Qwilt, for instance, are using emerging standards from the Streaming Video Technology Alliance (SVTA), which partners with CSPs to deploy CDNs deeply within their networks.

Today, over 150 CSPs have deployed Open Caching, with many more in the roll-out phase.

In APAC, Qwilt has partnered with Airtel in India, and J:COM, JPIX, and J-Stream in Japan, to implement an Open Caching-based CDN within their networks. Lim illustrated, “In this model, a live 4K stream of a major live sports game can enter the network at the main IXP, and then single streams will propagate through the core network to Open Caches in local exchanges in other major cities, and regional locations.

“These Open Edge caches are then each used as origin servers to distribute, in aggregate, millions of live streams to local viewers over the last-mile network.”

Can CDNs be the scourge of content piracy in APAC?

With piracy still rampant in many APAC countries, CDNs may well turn out to be an unsung hero in the continuing fight against content theft in the region.

CDNs, says Lim, are typically content agnostic, which is useful for content providers that wish to implement anti-piracy methods such as digital rights management (DRM) encryption, dynamic watermarking, and in the prevention of playback on devices that have fail High-bandwidth Digital Content Protection (HDCP) validation. 

He added, “In addition, more modern Open Edge-based CDNs can run a localised application for each user session. This ability allows for more creative options such as interactive content, localised ‘in-stream’ ad insertion, and even immersive video game streaming services with incredibly low latency.”

For Broadpeak’s Sterkers, the nature of OTT streaming technology offers many new opportunities for video content, particularly in the domain of security. “OTT relies on standard Internet technology, meaning a lot of proven security tools or methods are already available to protect the CDN and the system in general — including Transport Layer Security (TLS) encryption and authentication, access control tokens, anti-Distributed Denial-of-Service (DDoS) measures, web application firewall (WAF) application protection, and more,” he highlighted,” said Sterkers, adding that the individualised nature of network-users’ connections also allow for tighter control over the access to video content; and this includes distributing viewing rights one by one over the distribution network, allowing only authourised devices to connect to the CDN, and setting unique watermarks on each user’s content to help tackle piracy.

Beyond tackling piracy, individualisation also allows for many other strategic applications, like targeted advertising and other personalised services, which addresses service providers’ need to monetise their content.

“This too, is a critical aspect of OTT streaming, and the more streaming services evolve towards personalisation, the more an efficient CDN matters,” Sterkers concluded.