Cbeyond’s efficient bandwidth binge

Cbeyond Communications, an Atlanta-based service provider, is something of a standout among the legions of carriers pushing voice-over-IP services to small and medium businesses. In addition to providing VoIP services, the company offers a T-1 equivalent service that is striking a chord with users that view T-1 service as a premium high-capacity offering.

“The pitch is that for roughly what you’re spending on DSL, long distance voice and local voice, we’re going to give you equivalent voice service--and oh, by the way, you’re going to get a T-1 to the Internet,” said Chris Gatch, chief technology officer of Cbeyond.

The carrier is able to provide the service through what it markets as dynamic bandwidth allocation. Using an integrated access device at the customer premises and multiplexers in collocation cages at incumbent carriers’ facilities, Cbeyond can provide a full T-1 to customers when no voice traffic is being transmitted. As users begin sending voice traffic, bandwidth for data traffic is reduced to accommodate it.

“It’s not like a traditional bundle, where the T-1 is channelized and you have separate data and voice capacity,” Gatch said. “You get the full T-1 when you’re not on the phone.”

Cbeyond’s ability to blend voice and data into a single-network high-capacity offering typifies the needs of many carriers. That has become increasingly important over the last few years, particularly as the line between voice and data services is erased in enterprise organizations. Much of that push for convergence comes from the rapid adoption of VoIP services in the business market. At the same time, all but the largest enterprises have consolidated formerly separate staffs for data and voice services into single units.

For carriers, the need to provide converged services has become particularly important in light of an increasingly crowded competitive landscape that includes traditional facilities-based carriers, application service providers trying to add value to big-pipe services, and even a handful of cable operators that are nibbling at the edges of the market with Ethernet services.

Because voice is quickly becoming just another application in a data stream that already is highly commoditized, many carriers are looking to slash their cost of providing services. For competitive carriers, much of that savings comes from the ability cut down on the amount of real estate that they need to lease from incumbents. Cbeyond often touts the fact that it has an all-IP network and is what incumbent carriers would build if they could start all over.

“We’re not staring down any legacy network equipment,” Gatch said. “We already run a pure VoIP model and today we put out the IAD out at the customer premises. Everything behind that is VoIP.”

In the CBeyond architecture, voice and data traffic is sent out over Cisco Systems’ IADs and aggregated at collocation points using Telco Systems’ M13 multiplexers. From there, much of the voice traffic is routed to the local incumbent or a long distance carrier for completion. In fact, the economics of the interexchange market have devolved to the point that in many cases, it’s cheaper to have another carrier complete calls than to carry traffic on net, Gatch said.

“In some cases, it can be more expensive to do it yourself,” he said. “That’s a tough game to be in right now and unless you’ve just got huge economies that you can bring to the table, it’s not something we’ll do.”

On the data side, the same principle applies but is intensified because Internet traffic carries virtually no ability to charge a premium.

“It’s really not economical to haul Internet traffic anymore,” Gatch said. “We dump off that as fast as possible.”

In some instances, customer traffic first hits the tandem office, where it is aggregated. More often than not, the decision on where to aggregate traffic first is based on the customer’s location, with voice and data streams going to the closest point of presence regardless of whether it’s labeled a local or a tandem collocation.

Signaling for voice traffic, as well as some of the announcement services and e-mail services, are handled via the company’s two data centers in Atlanta and Dallas. The objective, according to Gatch, is to keep local calls--which make up the bulk of the traffic--within the local network.

“It’s a majority of the calling, but not an overwhelming majority,” he said. “It’s probably in the range of 65%.”

Aggregating the remainder of the traffic in the an efficient manner falls largely to Telco Systems’ M13 multiplexers, which use an architecture that allows carriers to combine multiple line-side T-1s in a minimum of space.

“It’s really the space savings that has a lot of people interested,” said Larry Asten, president of Telco Systems’ CEO. “You can go up to a lot more aggregation capacity in a frame with substantially less real estate than you’d normally need. The other real estate savings comes from utilizing the EdgeLink hub and migrating existing traffic into that.”

Perhaps just as important as real estate savings is the ability to cut out the amount of wiring and other peripheral equipment needed when stacking traditional multiplexers.

Telco Systems’ latest iteration, the EdgeLink hub, is actually nine EdgeLink 100 units combined in to a 5R-high box. Up to five hubs can fit into a standard telco rack and aggregate 1260 T-1s. Without the hub, telcos would be limited to 30 M13s, which would equal out to 840 T-1s.

Gatch said it isn’t simply the ability to provide high-level aggregation that sold Cbeyond. Like most network architecture decisions, it boils down to economics.

“It’s definitely the economics at the densities we think were going to have,” he said. “The economics are vastly different at different sizes.”

Because Cbeyond typically serves small businesses, much of that traffic consists of groups of T-1s. That’s where Asten believes Telco Systems has hit a sweet spot with the EdgeLink hub, which can aggregate up to 252 T-1s from a 5RU configuration.

The ability to combine that much capacity in a limited space will become even more important as business users begin looking demanding more bandwidth for VoIP-related applications that run over the same network. Currently, Cbeyond offers packages that resemble something more along the lines of bundles versus applications that rely solely on a VoIP service. About 40% of its customers buy both voice mail and e-mail packages along with voice.

“One of the areas we’re focused on is security,” Gatch said. “It’s something small businesses don’t have the expertise to understand and often times don’t have the resources to tackle.”

Part of the reason the company hasn’t rolled out applications that rely strictly on VoIP as a base is its belief that most businesses won’t necessarily migrate to a hosted solution. That runs counter to much of the VoIP segments thinking, however.

“We've gotten the picture that the network-hosted solution is picking up decent momentum in relative terms among the SMB and smaller enterprises,” said Brian Washburn, senior analyst of network services for Current Analysis.

However, according to Gatch, Cbeyond is exploring all options but thinks initially the majority of its market will want a premises-based solution.

“We have looked at the hosted model of the number of times, but right now we’re looking at supporting the IP PBX,” he said. “Most small businesses are going to buy IP PBXs because there are so many choices of companies making them at this point. We think there will be a small percentage of the market that will go to hosted, but we think the majority will stay with PBXs.” he said.