September 2, 2008

Ethernet Testing—More Standardization Needed

By Monta Monaco Hernon

As metro Ethernet continues to build momentum, particularly as a way to attract the small to medium sized business (SMB) market, testing tools - both for service provisioning and measurement - are evolving. (For more on Ethernet testing for the SMB market, click here.) Standards bodies, including the ITU, IEEE and the Metro Ethernet Forum, are working to effect a unified rather than a proprietary approach.

Operators say that the standards work to date, particularly MEF 9 and MEF 14 certification (for more on the MEF, click here), has allowed carrier-grade Ethernet to mature into a fast, scalable and reliable service. However, they add that more remains to be done, particularly in the area of performance measurement.

"If there was a negative perception in the past, that is going away," said Darren Wolner, Time Warner Cable senior product manager. "Standardization of performance measurement will be critical in providing customers with the overall view of the metrics that are important to them," he added.

The twain shall meet

While RFC 2544 tests generally are for service turn-up, they also have been used for troubleshooting. "There are some vendors who suggest that a line rate test launched on a demand basis is not a real measure of the service that is delivered to the customer and that in service performance measurements are required. We agree," said Robert Kuse, senior project manager, Cox Communications.

Cox is hoping that the IEEE 802.3 Ethernet Working Group (in particular 802.3ag and 802.3ah) and ITU-T's Y.1731 will provide it with the desired in service performance capabilities.

"These tools have not been fully implemented by all vendors," Kuse said. "This limits our visibility and causes us to deploy service edge devices (NIDs) that have these capabilities."

Vendor work

From a vendor perspective, EXFO Electro-Optical Engineering's products adhere to RFC 2544, which Claudio Mazzuca, EXFO director, transport and datacom product line management, would like to see augmented to qualify multi-services or tiered services in a network.

Last April, EXFO acquired Brix Networks, along with a suite of service assurance solutions. The company is addressing the problem of measuring Ethernet performance from the edge of the network to the CPE or from the cellular backhaul to the tower.

"Historically, the solution has been to deploy more appliances," said Kaynam Hedayat, senior director of product management and strategy at EXFO service assurance solutions. "This is not cost effective .... Standards are emerging that enable end points to act as reflectors for testing purposes."

- Monta Monaco Hernon