Archives

By Jonathan Tombes, Senior Editor

The SCTE's Digital Video Subcommittee (DVS) digital program insertion protocols meet a pressing need, but industry players are still concerned about getting insertion right.

The new standard, DVS 380, governs communication between servers and splicers. It gives legs to the digital cue tone standard, DVS 253, passed in late 1999, which addressed the problem of digital streams hitting headends with only dual tone multi-frequency (DTMF) cueing methods available.

"In a digital format, there is no way to provide DTMF cueing," says Paul Woidke, chair of the DVS Working Group 5, which is responsible for developing digital program insertion (DPI) standards.

Taken together, the two standards address the need of operators to graduate their programming to digital tiers without leaving local advertising revenue on the table. DVS 253 also addresses operators' need for managing cases such as live events that exceed their scheduled slots.

"They can lose a spot that's worth six figures, and substitute something worth $25," John Eberhard, ESPN's director of technology and distribution, says. The intelligence of DVS 253 enables better management of these ad avails.

Making this business work requires encoders on the programming side that incorporate the DVS 253 cue tone, and splicers and servers on the operator side that are DVS 380-compatible.

Scientific-Atlanta has demonstrated encoders whose 253 signals are interpreted by splicers, but is still working on software for the control system, David Wheeler, director of marketing for S-A's media networks sector, says.

ESPN supplier Motorola is incorporating 253 into its External Trigger System, Eberhard says.

Meanwhile, the standards will enable server vendors, such as SeaChange, nCUBE and EMC, to interoperate with splicers, whether they come from Cisco Systems, Harmonic, Terayon, or from someone new.

"Now we can say, 'Write to 380 and we'll play together," Joseph Ambault, SeaChange International director of advertising systems, says.

Getting it to mesh

But while these standards advance the field of digital insertion, questions remain about coordinating all the pieces.

"We're very concerned about misuse of these systems," Eberhard says. "And if you talk to my counterparts at Viacom, Turner and USA, you will hear identical messages."

The problem is the need for bit-rate management in systems where uncorrelated statistically multiplexed services have been bundled into a multiplex with more content than was originally distributed by the networks, Eberhard says.

"They may have content stored, for example, at 6 Mbps for the local Ford dealership," he says. "They are now trying to insert that into a network that is running at an average of 4 (Mbps)."

What happens? Bit rates have to drop on all other networks to make this fit, he says.

The problem is compounded by having to insert on more than one network at the same time, as in the case of ad campaigns designed to out-fox the channel surfer.

Ad server market leader SeaChange also recognizes the issue. "You can blow up multiplexes in numerous ways," Ambault says.

Eberhard says recognition of the problem is growing. "The new buzzword within [Working Group 5] is multiplex management."

But Eberhard says the Working Group is hesitant to tackle this problem because its solution lies not with new standards but rather "best practices," discussion of which lies outside the SCTE's purview.

The search is on to find the right venue to advance the discussion to the next level.

As far as DVS 380 itself goes, Wheeler and Eberhard say CableLabs is getting into action, with a live demo being planned for June.

"ESPN has volunteered transponder time to coordinate the satellite tests," Eberhard says.

 Back to June 2001 Issue

Access Intelligence's CABLE GROUP
Communications Technology | CableFAX Daily | CableFAX's CableWORLD | CT's Pipeline
CableFAX Magazine | CableFAX databriefs | Broadband Leaders Retreat | CableFAX Leaders Retreat