Any-to-any upgrade strengthens business model for FTTC

May 1, 2004

If you thought cable companies had backed away from business services, the lull before this year's voice over IP (VoIP) storm may have given a false sense of security. Like many multiple system operators, the business services arm of Cablevision Systems will start to migrate its 2,320-route-mi fiber network to IP/MPLS this year in pursuit of an any-to-any service model.

Cablevision's wholly owned subsidiary Lightpath (Bethpage, NY) is a facilities-based local exchange carrier (LEC) that targets a range of business customers, from healthcare, financial services, and government to small and mid-size enterprises in the metropolitan New York area, which includes New York City, Long Island, Westchester, southern Connecticut, and northern New Jersey. Lightpath also sells wholesale services to other service providers and counts many wireless carriers among its clients.

"Our end goal—which I thought would be five years out, but is probably going to become a reality in the next 18 months—is to build an optical network that is protocol-agnostic, that is essentially using a single protocol like IP to transport any type of traffic across the network with guaranteed service levels," says Lightpath's Brian Fabiano, senior vice president of network services, New York metro area.

The LEC, which began deploying fiber infrastructure in 1988, operates a 10-Gbit/sec DWDM network consisting of 397 SONET rings with five Lucent 5ESS voice/ATM switches in the markets of local incumbents Verizon Communications and SNET. Lightpath offers a range of integrated voice, data, and Internet services at DS-0 to OC-48c line rates. The carrier often shares Cablevision's consumer infrastructure by leveraging unused conduit, rights of way, or attachment rights to quickly put fiber up a pole, for example. The Lightpath network is maintained and monitored by a network operations center in Hicksville, Long Island. Today, more than 1,655 commercial buildings are connected to the network via fiber.

Lightpath's original business model meant bringing fiber to the curb (office parks) or to each client's premises and deploying a SONET multiplexer in those locations to deliver end-to-end services. The problem was the carrier needed a certain level of revenue to justify the build. Like many other carriers, Lightpath, which reported $178 million in revenues last year, is working on improving its business case by increasing capacity to offer services while reducing the cost associated with its network.

"We are now taking that point of demarcation that was at the customer's premises and bringing it back to the nearest PoP [point of presence] and then deploying smaller, lower-cost equipment at the client's premises, devices that will support both Ethernet and TDM services in a price range of anywhere from $3,000 to $5,000 instead of a $25,000 SONET mux, channel bank, and router at the premise," explains Fabiano.

The business objective is to lower network costs and operating expenditures by deploying new technology, which in turn will allow Lightpath to cost-justify bringing more customers on-net. The new technologies also offer more remote management capabilities, which should help lower the carrier's operational costs.

Lightpath last year started to upgrade its OC-48c (2.4-Gbit/sec) network core to OC-192 (10-Gbit/sec) DWDM by deploying Nortel Networks' Optera Metro 5200 multiservice platform. Much of the year was spent characterizing the network's 15-year-old fiber to make sure it could handle the upgrade and planning the transformation, which involved placing equipment in all key central-office and headend locations. The DWDM upgrade was finished in March. In an effort to increase its capacity, Lightpath will initially operate 2.5-Gbit/sec wavelengths on the core route, then migrate to 32 protected 10-Gbit/sec wavelengths and eventually 64 protected wavelengths.

The next step in the network's transformation is to deploy an IP over MPLS core using Cisco Systems' ONS 15454 platform to upgrade to a network that can transport multiple protocols over an "any port-in, any port-out" architecture. "We knew that this is where we had to be, so we selected a hardware vendor that had a vision and a roadmap that would get us from where we were a few year's back to where we needed to be in the future," says Fabiano. LightPath originally deployed Cerent's 15454 optical multiplexer, a product line acquired by Cisco in 1999, to deliver T1 and TDM services. Now it will use the same platform to launch metro Ethernet, 10/100-Gbit/sec Ethernet, Fibre Channel, and SAN services. "We picked an architecture that scales with the new services, so you are just inserting blades into the chassis and not having to rip everything out and do major forklift upgrades, which a lot of providers have to do to get there," Fabiano says.

"Cisco has been a very good partner for us," asserts Fabiano. "At the time, we had to go to the dense wave core—Cisco was developing a product that at that point wasn't ready for primetime, so we had to go with the best provider at the time, and that was Nortel. But I'm envisioning in the next 18 to 24 months, when their product gets rolled out and market adoption becomes more stable, that is something we will probably migrate to."

Going forward, Lightpath will build out its MPLS core, work to define new services, and attempt to reach more customers using potentially non-line-of-sight wireless and free-space optics in addition to fiber. The carrier will also roll out a commercial VoIP service this year. Parent company Cablevision last year launched Optimum Voice, an unlimited local and long-distance VoIP service, and reports nearly 29,000 residential customers. Lightpath will initially offer VoIP to business customers over Cablevision's consumer infrastructure, which features a Siemens softswitch.

"We'll start out using a gateway to do IP-to-TDM conversion because our 5ESS switch still has a lot of capacity left. Once that is exhausted, then we are going to roll out our own softswitches," says Fabiano. Initially, the commercial VoIP will be very similar to the residential VoIP, with value added through services such as professional installation and higher customer care. Once the VoIP is rolled out on Lightpath's business services network, it will be dramatically different from a service-level perspective, notes Fabiano. "Today on voice over IP over cable infrastructure, although voice packets get priority, it is still kind of a best-effort service; there is no guaranteed quality of service," he explains. "In our enterprise deployment, there will be guaranteed quality of service. And it will be able to scale to very large deployments on a much more resilient infrastructure."