Smartphones and tablets have ushered in the age of on-demand content delivery. Mobile video downloads are expected to explode from 429 million in 2011 to 4.2 billion by 2015, for instance, according to recent estimates.
To ensure network performance and keep costs manageable, service providers are increasingly deploying content delivery networks (CDNs) to handle the demand. One such platform that is particularly well-suited is the Velocix Digital Media Delivery Platform by Alcatel-Lucent (News 
- Alert).
In creating on-network CDNs, service providers are minimizing the distance content travels over the network and delivering it more quickly and reliably. On-net CDNs originate content at the edge of fixed and mobile networks, which both brings it closer to consumers for fast delivery and reduces congestion and network disruption.
On-net CDNs pose a number of challenges for service providers, however, according to a recent paper by Alcatel-Lucent, “CDN Interoperability.”
“Today’s on-net CDNs exist as standalone solutions and offer coverage that is typically limited to the service provider’s network footprint,” Alcatel-Lucent noted in the paper. “Limited coverage can hinder a service provider’s ability to partner with large content providers and maximize return on CDN assets.” Further, “this sort of complexity may prompt content providers to work with a single third-party CDN service instead of working with multiple service provider CDNs.”
For on-net CDNs to work, the paper argues, interoperability among CDNs is essential.
The primary reasons for developing CDN interconnect (CDNI) are footprint extension and traffic offload, according to the paper.
Extending the service provider’s CDN footprint makes sense both as a bilateral federation from one on-line CDN to another, and as a bilateral federation from on-line CDN to third-party CDN services.
“A service provider can also use bilateral federation with other on-net CDNs to ensure a seamless user experience for nomadic subscribers who roam beyond the reach of its network or CDN footprint,” Alcatel-Lucent explained in the paper. The ability to interconnect with third-party CDNs makes sense because it helps the third-party CDN deliver a better quality of experience on the network, and because it can reduce a CDN provider’s CAPEX and OPEX (News - Alert) by limiting its need for over the top capacity, caches and network connectivity.
In terms of traffic offload, CDNI allows for offloading for resilience, added functionality or dimensioning.
“Scaling delivery capacity to cope with demand for large sports events, popular live broadcasts and new film releases can be particularly challenging,” notes Alcatel-Lucent. “In service provider networks, it is typically very difficult to deploy high volumes of CDN capacity at short notice or on demand.”
Before adopting strategies for CDNI, however, service providers must ensure that their CDNs include key building blocks and meet the technical requirements. These include service functions such as:
- Management
- Routing and monitoring components
- Storage functions that enable CDNs to easily ingest content
- Delivery functions that handle physical and over-the-top content delivery
The CDNs also must have the ability to offer request routing APIs, content metadata, delivery logging and content control.
The Velocix Digital Media Delivery Platform by Alcatel-Lucent is positioned particularly well to help service providers develop CDNI, according to the paper. The Velocix (News - Alert) CDN already is being used in production environments to connect on-line CDNs even while this increasingly important interconnection is in the early stages of adoption. It features a range of APIs to help with interconnection, and it has been used for single, shared and multi-tenant interoperability, the paper noted.
Whether using Velocix or a different technology, however, forward-thinking service providers are paying attention to CDNs and the benefits they bring to their network in terms of performance and for positioning them in one of the fastest growing segments of the market.
Edited by
Peter Bernstein
