A single solution helps to provide out-of-footprint connectivity and monitoring

To serve key customers, Independent telcos sometimes need to offer connectivity outside their home turf — and increasingly, business customers are requesting Ethernet connections with guaranteed service level agreements. But meeting SLAs is challenging when one carrier must buy connectivity from another, as it can be difficult to determine where any degradation of service is occurring.

To address this challenge, more and more Independent telcos are turning to Ethernet demarcation devices (EDDs), also known as network interface devices. Such devices provide performance monitoring and testing, and also deliver Ethernet connectivity over the final leg of the connection, which may involve Ethernet-over-T-1, Ethernet-over-Sonet or other types of transport.

“We fill two needs,” said Chip Redden, vice president of marketing and product management for EDD manufacturer Overture Networks. “Customers can reach any location, whether it's served by fiber or copper, and we can manage services that ride on the transport layer that may belong to a partner company.”

When one carrier purchases connectivity from another, Redden said “you have to manage the network-to-network interface. If I lease from you, I need to know what I'm getting. The connection needs to be managed end to end.” If customers were not able to use equipment such as what Overture provides, Redden said, “nine times out of 10 they would have to walk away.”

Overture has sold heavily to Tier 1 telcos and smaller carriers such as Deltacom. As a competitive regional carrier, Deltacom faces problems similar to those of smaller incumbents. “We have Ethernet rings in five cities, but we have to depend on an alternate access provider or traditional carrier for a loop,” said Tony Tomee, executive vice president of sales and marketing for Deltacom. Demarcation equipment, he said, “allows us to give customers a native Ethernet connection into a customer premises box. That box handles the interface to a loop back into our network. And we have the ability with this box and its monitoring capabilities to have SLAs to the customer premises.”

Although service providers could use a switch rather than an EDD, that would be overkill, said Eitan Schwartz, vice president of pseudo-wire and Ethernet access for RAD. Schwartz described the EDD as a “superset of a media converter.” An EDD does everything a media converter can do while providing additional functionality such as service classification.

RAD has sold its EDD to international carriers and Independent telcos, among others, and has found the ability to provide network performance metrics to be critical. “The out-of-footprint carrier needs to provide a consistent look and feel for customers. It can't tell them they'll get an SLA in this town of X and somewhere else they'll get an SLA of Y,” Schwartz said.

By isolating a connection, the retail service provider can establish a baseline performance level, Schwartz added. “Six months down the road, if a threshold objective was exceeded, they can go to the transport provider and say, ‘Did you do something to the network?’ Maybe they added another customer down the road and that compromised [existing] customers.”

Customers buy EDDs to ensure that Ethernet is a cost-effective service to manage, said Scott Sumner, vice president for Accedian Networks, another EDD manufacturer. “Ethernet is cheap to deploy, but there can be a lot of truck rolls because there is hardly any visibility,” he said. Warwick Telecom, a consortium of small incumbent telcos in Quebec, has found that Overture's offering can pay for itself by saving just a single truck roll, Sumner noted.

Accedian's solution is implemented in pure silicon using in-line elements. “It's like deep packet inspection,” Sumner said, adding that the solution handles all packets at wire speed up to Gigabit Ethernet. Because that approach does not add latency, it makes Accedian's solution suitable for use with IPTV and voice over IP, Sumner said.

Telecom Warwick affiliate La Compagnie de Téléphone de Saint-Victor recently deployed an alternative application of Accedian's solution to support IPTV. The equipment is used in “a point-to-point connection between the two networks to amplify the signal,” said Marco Plante, a technician for La Compagnie de Téléphone de Saint-Victor.