Building Content Distribution Platforms over Flexible Optical Networks Paul Wright (BT) paul.3.wright@bt.com Daniel King (Lancaster University) d.king@lancaster.ac.uk
Broadcaster Industry Trends Delivery of content, especially of video, is one of the major challenges of all operator networks due to massive growing amount of traffic Growth of video traffic is driven by the shift from traditional broadcast media Increasing video bitrates SD HD Ultra-HD Higher frame rates Increased color depth Transmission over IP Increased flexibility and scalability Moving towards end-to-end IP Remote production Less reliance on outside broadcast trucks How might SDN and flexible optical networks help deliver these?
Media Networks Studios Broadcaster Production Terrestrial Stadiums Archive Satellite Outside Broadcasts Playback Internet Contribution Distribution
Media Contribution Networks Traditional fixed contribution network Fixed Metro/Core Network Cameras OB truck at venue Compressed backhaul feed from exchange Production studio Play-out Centre CLOSED CLOSED CLOSED CLOSED Potential SDN based dynamic contribution network SDN backhaul SDN SDN core Cloud production/ archiving SDN Play out network Cameras Production studio and play out facility OPEN SOFTWARE DEFINED NETWORK
Video Encoding for Media Contribution Two main encoding standards: Uncompressed: Serial Digital Interface (SDI) Compressed: Motion JPEG High bandwidth services: Name Video Bitrate SD-SDI 480i/576i 270 Mbit/s HD-SDI 720p/1080i 1.5 Gbit/s 3G-SDI 1080p 3 Gbit/s 6G UHD-SDI 4K 30fps 6 Gbit/s 12G UHD-SDI 4K 60fps 12 Gbit/s 24G UHD-SDI 4K 120fps 24 Gbit/s
Media Workflows Multiple high bandwidth media flows Multiple cameras and sources Resilience Video flows typically have 1+1 protection Varying durations Minutes to permanently connected Schedulable Resources can be booked in advance
Proof of Concept Demo Software Stack Scheduler XML Video Orchestrator Aperi Media Edge REST-APIs OpenDaylight OpenFlow Agents OpenFlow Scheduler: Video flow scheduler and resource manager Video Orchestrator: Provides broadcast video application specific control, talking to both network and video devices OpenDaylight (SDN Controller): Discovers network topology and converts from flow requests to OpenFlow commands OpenFlow Agents: Receives and implements OpenFlow commands onto the network elements
Increasing Video Distribution Complexity The Content Distribution Network Operators deploy proprietary cache nodes into the network to store video content CDN cache nodes are dedicated physical appliances or software entities CDN controller objective is to select a cache node (or a pool of cache nodes) The CDN controller is a centralized component, and CDN cache nodes are distributed Content Distribution Optimisation Deploy content as close to each set of users as possible Content Routing Route the users request for content to the closest available content store or content engine Content Peering Gateways Which peering point to use? How to ensure optimal multi-domain paths? Can we apply intent/policy?
The PCE has a Role for Video Distribution The PCE is integral and here to stay as a functional component of an SDN platform for video distribution and storage Re-use of components and protocols makes sense Implementing PCE as a distinct unit with the SDN architecture provides a number of benefits: Scaling Load-balancing Resilience Multiple forwarding technology support (Packet & Optical) Rapid advancement of algorithms SDN should be seen as a critical part of a wider view of network operation However, gaps exist!
Video Contribution and Distribution Networks Observations and Issues Application specific orchestration layer needed Can this ever be generalized to be application agnostic? How might we define the service? Are information models available? PCE being performed in multiple locations Where should the PCE element(s) actually be located? Is the PCE a candidate for Network Functions Virtualisation (NFV)? How do we scale, load balance and ensure resilience for? Speed at which path computations are provided Can paths be determined and provisioned any quicker? How can we combine offline (planning) and online (real-time) requests? Multi-layer support (packet layer over flexible optical networks) Placement of video services at both the packet and optical layer (bandwidth dependent) Application-Based Network Operations provides a framework but deployments are limited Application of Policy/Intent to the path computation request