Multiscreen Expansions Raise Bar on Private CDN Strategies

Jon Haley, VP, marketing, Edgeware

Jon Haley, VP, marketing, Edgeware

By Fred Dawson

September 19, 2013 – As pay TV service providers strive to outperform over-the-top competitors, one of their key advantages can be found in private CDN technology solutions that are making it possible to deliver superior multiscreen services cost effectively.

A growing number of suppliers, some with roots in public CDN services, have taken up the private CDN challenge, which goes well beyond the traditional caching role of CDNs. While most of these suppliers have based their strategies on processing capabilities tied to commodity off-the-shelf (COTS) servers, one that hasn’t, namely, Edgeware, is leveraging unique software capabilities tightly integrated with high processing horsepower to address some of the most pressing cost and performance concerns now on the minds of service providers.

“We’ve introduced innovations in response to demand from service providers who want to be able to differentiate their multiscreen services from OTT suppliers like Netflix,” says Jon Haley, vice president of marketing at Edgeware. “Quality of experience and managing issues of scalability are now top priority in this market.”

A number of service providers have deployed Edgeware’s latest advances in tests and now are getting back offices ready for commercial launches, Haley says. “Service providers are expanding multiscreen to include live services, including features like catch-up, restart and network DVR, while adding more devices,” he adds. “We’ll be announcing some of these new customers soon.”

With these service expansions market requirements have reached a point where old approaches are unsustainable, Haley notes. Service providers must either vastly increase server, storage and other resources within the current headend-centric architecture or leverage an advanced private CDN architecture to balance loads and support these new applications more effectively across all central and edge resources.

Analytics, too, has become a major challenge when it comes to having to monitor the flows of tiny fragments within each streaming session in real time. “When you go over to adaptive bitrate (ABR) to stream content, the delivery of one asset to a single device consists of sending thousands of small chunks,” Haley says. “If you want to monitor all those streams in real time you end up with millions of log files.”

Edgeware’s latest advances, including origin server load balancing, backhaul management, companion-device support and advanced analytics, follow last year’s introduction of the Convoy suite of software modules for the firm’s flagship Distributed Video Delivery Network (D-VDN) platform. As previously reported, the Netherlands’ largest cable operator, Ziggo, was an early adopter and has since been leveraging the D-VDN system in a shift to an OTT mode of distributing next-generation services to connected devices.

Along with adding scaling, quality-of-experience (QoE) and data collection functionalities to the platform, Edgeware has introduced a new generation of its hardware appliance, the Orbit 3080, which features 80 gigabit-per-second wire speed video streaming from a single rack unit. The Orbit 3080 provides a ten-fold increase in throughput per rack unit when compared to a high-performance, generic server, says Edgeware CEO Joachim Roos. The difference is even more significant given how ingest operations as well as management system and monitoring overheads impact generic server capacity, he adds.

“Today, peak audiences on the Internet are still tiny compared to broadcast TV,” Roos says. “If Internet and cloud TV services are to compete, a drastic change in the delivery capacity is needed and that is exactly what this solution provides.”

Two key enhancements to the D-VDN software modules are designed to improve scaling efficiencies. One is the Origin Accelerator process, which allows the D-VDN platform to offload and load balance all origin ingest and playout functions, eliminating the need to invest in costly load balancers.

The need for this capability stems from the fact that the amount of content being streamed at any moment from any origin server is escalating rapidly with higher content volumes and greater usage by subscribers. While the CDN edge servers can handle the most popular content, the “cache miss” count, which is to say the volume of requests for un-cached content going back to the origin servers, is rising rapidly.

The situation has grown especially worrisome with the introduction of live channels in multiscreen services, which greatly expands how much content each origin server must simultaneously ingest and deliver. “With live content, you end up with a huge amount of requests going back to origin servers even if you have an efficient CDN system,” Haley says.

“We’ve seen multiple cases where origin scaling becomes the bottleneck in premium multiscreen services, creating chaos in an operator’s network,” he adds. “So we’ve moved the load balancing of the origin servers into the CDN to minimize overloads and create redundancy in the event of failures.”

Complementing the origin server load balancing process is the new backhaul management system, which spreads requests for server resources across all the D-VDN servers in a network POP. With the ability to intelligently distribute content and client requests over multiple servers in a content-aware cluster, the operator increases the cache hit rate and reduces the use of the backhaul network for cache-misses, Haley explains.

“Service providers are acquiring rights to larger back-catalogs and longer catch-up TV recording windows,” he says. Caching efficiency in delivery networks declines as more content is added and backhaul networks become congested. Upgrading the backhaul network is capital intensive and requires long lead times, so a smarter solution is to retain cache efficiency, he explains.

Edgeware has also made it possible to use the D-VDN platform to facilitate second-screen companion-device apps tied to supporting program selection and recording.  Essentially this new capability ties the set-top into the home LAN behind the router. “You don’t have to change protocols or go to ABR streaming,” Haley says. “You use standard UDP streaming.”

On the analytics side Edgeware has expanded the capacity and flexibility of applications tied to its optional monitoring modules. Each Orbit delivery server aggregates requests into “sessions” and fragments into “assets,” which reduces thousands of log entries to just a few for each session, Haley says. These are collected and analyzed in real-time, using much fewer system resources on the Edgeware Convoy Management System.

Logs can be made available via an integration API to specialized analytics applications such as Skytide Insight supplies or they can be presented in reports via an optional analytics GUI within the Convoy system, Haley adds. Examples include content popularity, viewer engagement and delivered quality, segmented by consumer IP, region, device type, delivery server and origin server.

“Cost effective delivery of large time-shift and back-catalogue services is a real challenge, as is true, real-time monitoring of the delivered quality as the service scales,” Haley says. “These new features were requested by customers striving to delivery highly differentiated, multiscreen services.”