Canadian broadcaster gets dynamic

The Canadian Broadcasting Corp. (CBC) is 67 years old; judging by the words of one insider, its network feels even older.

Granted, Anthony Caruso, the CBC’s Montreal-based director of technology, figures the broadcaster’s network has merely two decades under its belt. But in high-tech time, 20 years is ancient, and the CBC wants to replace the ageing infrastructure with modern equipment – a network that brings together myriad media, but does so with cost effectiveness and performance requirements in mind.

The CBC in January tested Net Insight AB’s Nimbra One modular switch. Caruso said he was impressed. “It had quality of service. It was very scalable.”

The Nimbra One employs Dynamic Transfer Mode (DTM), a protocol that Net Insight says is just right for converging voice, video and data onto one network.

Dan Lutter, Net Insight’s Chicago-based vice-president of North American sales, said Ericsson designed DTM ten years ago, and Sweden’s Royal Institute of Technology investigated it for five years. Stockholm-headquartered Net Insight was created in the late-1990s to market the technology.

DTM is circuit-switched just like synchronous optical network (SONET) technology. Although packet switching is popular these days, Lutter said circuit switching is more robust – and “robust” is the operative word when it comes to the CBC’s needs.

Caruso said the CBC requires guaranteed connections to send video to production – an important aspect of the Olympic Games in Athens in 2004, when the broadcaster plans to send raw video from the event to Canada for editing.

“You cannot have 80 per cent probability” that the pictures will reach their destination, he said. “We need 100 per cent. That’s what this technology offers.”

Caruso also said DTM is more efficient than other circuit-switch technologies. For example, SONET isn’t very flexible, available only in predetermined sizes, such as 45Mbps and 155Mbps. A company seeking 60Mbps would have to purchase a 155Mbps connection, and write off the unused 95Mbps portion of the pipe, he said.

“With DTM, you can scale in chunks of 512 kilobits,” Caruso said, explaining that the technology affords close to 60Mbps, accommodating customers’ needs better than SONET does.

During the Net Insight trial, the CBC had a Nimbra One placed in Montreal and another in Toronto, connecting the two with fibre-optic cables supplied by Bell Canada. The switches had modules for Ethernet, E-1 (T-1’s European counterpart) and DVB-ASI, a Digital Video Broadcasting technology. The equipment employed an automated control plane for quick routing, and GMPLS for mesh protection and multicast provisioning, Net Insight said.

Caruso said the CBC “explored the technology from the point of view of quality of service, whether it could merge all the traffic – video, audio, radio and voice and data – into the same pipe….The test was successful, I’d say.”

Now it’s up to the CBC’s service provider, Bell Canada, to decide whether Net Insight’s Nimbra One platform becomes part of the carrier network. Caruso said there are certain challenges in that regard.

“[DTM] has some weaknesses. It’s not fully standardized. There’s no competition from manufacturers to produce DTM hardware, because nobody’s going to jump onto the technology until the standard’s in place.”

But Lutter from Net Insight said the European Telecommunications Standards Institute (ETSI) now calls DTM a standard. It’s just a matter of time before other standards bodies follow suit, he said.

Bell representatives have said in the past that the carrier explores new technologies and evaluates thoroughly before deciding on new vendor offerings.

Lutter said the Nimbra One DTM switch varies in price depending on configuration from approximately US$12,000 to US$30,000. For more info, visit Net Insight’s Web site,