Narad unveils cable technology

Start-up Narad Networks Inc. last month unveiled a plan designed to let cable operators offer high-speed Ethernet services over existing hybrid fibre coaxial (HFC) cable networks.

Narad’s system, known as the Virtual Fiber architecture, combines HFC units and Ethernet switches with back-office software, and lets cable providers create and deliver new services, such as voice over cable, VPNs and storage-area networking (SAN).

Until now, cable providers haven’t been able to successfully penetrate the business market, said Dev Gupta, Narad’s CEO.

“[Cable providers] don’t have the bandwidth. They don’t have the quality of service. And they can’t provide service-level agreements,” he said.

Narad’s gear will allow cable operators to get plenty of all three by utilizing unused frequency to create a combination Fast Ethernet/gigabit Ethernet network over the existing cable network.

HFC network providers only use spectrum up to 860MHz to provide service. Narad’s technology uses spectrum above 860MHz, so it doesn’t interfere with any traditional cable services, Gupta said.

On the infrastructure side, Virtual Fiber requires cable providers to install an optical box in front of cable optical nodes, replace cable amplifiers with Narad boxes called distribution switches, and replace cable taps with Narad boxes called access switches.

The distribution switches act as combination amplifiers/gigabit Ethernet switches, while the access switches provide traditional cable tap functions, Fast Ethernet access to end customers and gigabit Ethernet uplinks into the cable network. One access switch can serve up to four customers.

On the customer premises, providers install a box, known as a Broadband Interface Unit, providing four 10/100 Ethernet connections and one traditional coaxial cable port. The units support IEEE 802.1Q virtual LANs and tunneling via Layer 2 Tunneling Protocol.

A content-management system lets providers offer services such as SAN applications and video on demand.

Narad’s system could be attractive to cable providers that are looking to serve the small and midsize business market, says Michael Howard, principal and co-founder of Infonetics Research.

“This could appeal to someone like a Cox (Communications Inc.) or Comcast (Corp.) that’s not just targeting the residential market,” he said.

However, Howard added, Narad can’t overcome all the hurdles cable providers face in appealing to business users.

“The problem for the cable companies is they still don’t have a lot of cable that bypasses businesses,” he said.

Narad’s Virtual Fiber product is slated to enter field trials in the fourth quarter and should be generally available in the first quarter of 2002. Pricing for the system begins at US$10,000 for the first customer, with increasingly lower incremental costs as customers are added.

Narad Networks, in Westford, Mass., can be found on the Web at