Companies are beginning to address the increased complexity of IP with solutions that integrate all components of an IP video network infrastructure — program acquisition from satellite, terrestrial and physical media sources in native IP, encoding, formatting, quality control/monitoring, scheduling, management and distribution via multiple media formats to the range of devices in the marketplace.
A tremendous amount of complexity must be encapsulated into such systems. But, when properly engineered and managed, modular solutions mitigate costs and often integrate with legacy infrastructures. Instead of complex, expensive installation of less flexible and less configurable equipment for video networks, IP solutions provide economies of scale in addition to bandwidth optimization.
The new media broadcast center
The new media broadcast center no longer conforms to the old paradigm of tape-based workflow, where there are multiple repetitive tape-based ingests from acquisition to production/preparation to transmission and/or archival. Tape-based workflow is hard to manage and track, and is a time-consuming and labor-intensive process with QC required at every stage. Where a traditional tape-based process follows a push-based workflow of steps being processed in a serial fashion, the newer file-based workflow methodology is more of a pull process, with an IP-centric workflow that allows different steps of the process to be simultaneously performed. (See Figure 1.)
New media broadcast centers are designed to support file-based workflow where content is ingested once and made available to all work centers simultaneously. The design is centered on IP-packet technology flowing on an IT network and accessing a central shared-storage facility. The central storage facility houses all media content, including essence, metadata and other associated content. Once content is ingested, it is transformed into a file format, metadata is aggregated, and assets are bundled into a package for delivery to central storage. Typically, this bundle is a SMPTE-standard MXF wrapper. The wrapper may contain a number of different streams of essence that are encoded with one or more varieties of codecs and tied to an associated metadata wrapper that describes material contained within the MXF wrapper.
Work-center access to central storage is allowed on an independent basis, based on previously established operational workflow rules. Automated processing is managed by a MAM system, which enforces and administers the rules. An all-IP, all-IT network architecture with file-based workflow brings efficiencies the media broadcast center can benefit from. Among these benefits are: centralized and on-demand scalable computing; fast/dense networking; scalable storage; reduction of over-provisioned and under-utilized resources; and virtualization and parallel processing.
IP's new-age infrastructure
In the new design, it is advised to segregate the control LAN from the mission-critical rich media LAN. While it may be appropriate to size the control network for Gigabyte Ethernet, the rich-media LAN is typically sized for 10GB Ethernet or higher. Most equipment uses Ethernet ports for monitor and control access. Having an Ethernet switch in each cabinet for aggregation reduces cabling.
The equipment and cabling design for the data-rate capacity of rich media should be sized for the present and future. With a data rate of 1.485Mb/s for 1080i HDTV, many facilities were designed to support up to only 1.5Gb/s. Today, however, some content providers are transitioning to 1080p HDTV. For the past two years, equipment manufacturers have provided equipment with 3Gb/s capability to support the move to 1080p. Concurrently, some consumer TV equipment manufacturers now demonstrate 4K HD and UHDTV that require higher data-rate capacities. (See Figure 2.) This can be a dilemma for center designers.
Central storage design
Central storage design has been moving from a general, parallel file system to a distributed networked file system. The clustered storage Distributed Networked File System (DNFS) is fast becoming the choice for central storage in the modern broadcast center. (See Figure 3.) It is a high-performance solution combining an intelligent DNFS with modular hardware that delivers simplicity and scalability. It combines three layers of traditional storage architecture (file system, volume management and RAID) into a symmetrical system that stripes files and metadata across multiple storage nodes within a cluster. Each node is given the intelligence to know the whole system layout and where each file or its parts reside.
With low-latency Infiniband switching for inter-cluster communication, it enables each node to share information with every other node on the system.
Considering the movement of file-based workflow to the cloud, the future central-storage facility will more than likely transition to IP-network-based storage derived from IT commercial-off-the-shelf (COTS) amalgamation of virtual machines. (See Figure 4.)
IP networking in the cloud
With IP/IT infrastructure and file-based workflow adaptation, there exists the fundamental technology necessary to allow much of today’s workflow processing to reside in the cloud. This is centered on rule-based workflow algorithms automated by a MAM system and built on a virtual infrastructure, allowing for deployment of multiple work platforms on shared hardware, operating systems and applications.
This software-based cloud solution offers lower upfront cost and provides high scalability with flexibility. Also, many content owners’ primary concern is asset security; however, digital rights management cloud solutions exist that protect content during the process.
A promise delivered
With integrated IP solutions, encompassing compression, advanced provisioning, path finding and quality assurance, broadcasters can create networks that can give greater efficiencies and resource and cost savings. IP has come of age, providing unique advantages across workflows and distribution.
—Tom Parish is senior vice president of broadcast technology, Globecomm.