Digital Transport Benefits
Headend Consolidation for Operating Benefits
BigBand Deep Digital Transport enables headends to be consolidated, resulting in several operating benefits. The combination of sophisticated media processing and IP transport using cost-effective GigE technology supports highly reliable, economical delivery of a broad range of video content over long distances instead of a network consisting of a large number of headends, each equipped with a similar assortment of equipment for receiving and distributing content, such as figure 1. A consolidated network consists of a few headends distributing digital content to less complex hubs over IP transport links. Video, voice and data traffic are all supported in a single transport layer, such as figure 2.
Figure 1: Two unconsolidated headends providing similar functionality
Figure 2: Headends consolidated using BigBand Deep Digital Transport, resulting in cost savings
Content is transmitted from headend locations typically using GigE over optical fiber, and can be transported hundreds of miles before signal re-generation is necessary. In addition, unlike its analog counterpart, digital transport allows video signals to be re-generated any number of times which, when combined with BigBand Networks’ superior de-jittering capabilities, results in digital video content being distributed over very long distances without impairment.
Service can also be extended cost-effectively to areas which had previously been considered unreachable due to technology or economic reasons. BigBand Deep Digital Transport is used to reach areas too sparsely populated to justify headend construction, or too remote from existing downlink facilities to be reached using RF transport. In addition, an operator has the ability to provide terrestrial distribution of content nationally.
In some cases, BigBand Deep Digital Transport is chosen to replace legacy digital transport equipment. Many of these older devices use proprietary protocols and require large amounts of bandwidth. The BMR, by contrast, uses bandwidth efficient industry-standard MPEG over UDP/IP transport protocols and improves bandwidth efficiency.
Headends can be connected in redundant configurations using BigBand Deep Digital Transport, protecting against a variety of problems spanning the degradation of a single program to the loss of a network facility. This enables an operator to improve service reliability, avoiding subscriber dissatisfaction and the potential for lost transactional revenues.
The BigBand BMR supports a variety of network topologies that interconnect locations including fiber rings, 1+1 linear systems and mesh configurations. Fiber rings with automatic switchover in the event of a service-affecting failure are particularly robust. The BMR supports a carrier-class switchover time of 50 ms or less.
A fiber ring provides two routes between all nodes. Traffic is transported over the primary path under normal operating conditions but, in the event of a serious impediment, is redirected to the backup path. The versatile BigBand BMR detects a failure and automatically reconfigures network connections virtually instantaneously.
The BigBand BMR also offers program level redundancy, a capability that achieves availabilities exceeding even those possible from network-level redundancy alone. In a redundant topology, each facility receives two identical video streams: the primary program source consists of inputs from local encoders, off-air feeds and satellite feeds, while the secondary programs are sourced from the backup headend via transport. Due to its video-aware networking capabilities, the BMR can detect a failure or significant degradation in any of the programs on the primary feed and automatically switches to the secondary source for these programs. Redundancy at this level dramatically improves availability and the subscriber viewing experience.
Figure 3: Protection switching spanning all OSI layers ensures highest service reliability
The wide-reaching capabilities of BigBand Deep Digital Transport combined with BigBand Digital TV Management enables a range of valuable solutions to be implemented economically, including BigBand Digital Simulcast, BigBand Video on Demand, BigBand Switched Digital Video and digital ad insertion. These solutions give an operator the ability to dramatically enhance network functionality, reclaim bandwidth and deploy new services and content.