Suitcasing Sonet: Sniffer provides seven-layer analysis for optical networks

Maintaining a network is no different from maintaining a car, a house or even a garden when it comes to this golden rule: Use the proper tools for the proper job.

Transmission speed and transport protocol developments have far outpaced field engineers' ability to test and analyze their networks. As service providers expand their use of packet-over-Sonet technologies, they need better tools to maintain them.

Network Associates' Sniffer Technologies business unit is introducing a tool that lets field engineers troubleshoot and analyze Sonet network backbones.

The Sniffer Pro Packet over Sonet network analyzer is portable and gives engineers visibility into all layers of network and application traffic.

"Although there always was a need, we've never had any equipment that lets us test Sonet," said Ed Wassall, vice president of North American field engineering for Ameritech's data networking solutions division.

The analyzer will be available next month. Wassall's group has been testing the tool on its Sonet-based backbone WAN and in its lab.

"It seems to be pretty stable. It performed the function that my post-sales engineers would need it for," Wassall said. "We want to understand how hot the signals are coming in [and] if there are any particular protocols that could be causing an issue as it relates to transmission over Sonet."

Other Sonet analyzers have been available but have been limited to physical layer testing, said David Colodny, director of product marketing with Network Associates' Sniffer Technologies division.

In addition to providing analysis capabilities for all traffic layers, the Sniffer Pro's 256 Mbyte capture buffer is large enough to allow real-time analysis at OC-3 and OC-12 speeds. Network Associates expects to offer OC-48 capabilities on the Sniffer Pro platform by the end of this year.

Ameritech's testing did not include OC-12 speeds. "We didn't have the capability to test at OC-12 here in our lab," Wassall said.

The analyzer uses a K6 300 MHz processor that enables high-speed capture filtering. The capture buffer is part of SnifferBook Ultra capture hardware.

"You can put in complex filters and still not drop packets. It's very important to be able to set filters and still capture at the line rate," Colodny said.

Bringing the capability for Sonet troubleshooting and analysis to the field engineer level is one of the main reasons Wassall already has earmarked money in his budget to purchase the equipment this year.

"From my standpoint, the capability to service a customer from a post-sales perspective is paramount. I have to have equipment that's intelligent enough to help me make decisions about what to do with problems a customer has presented us," he said.

Sniffer Pro's intelligence comes from its auto-sensing capability, where it detects the line speed, either OC-3 or OC-12, and adjusts automatically. It also has a dual-mode interface for single-mode or multimode fiber.

The media module that acts as the fiber interface is scalable. "As 1000BaseT or higher-speed ATM become available, the [module] will be interchangeable to provide investment protection," Colodny said.

Network Associates traditionally has been an enterprise player whose inroads to service providers has been the analysis of their backbone WANs. With the Sniffer Pro Packet over Sonet, the company brings a carrier-class tool designed for backbones and switched networks.

"It's gone beyond protocol analysis to really address real-time monitoring, the reactive troubleshooting piece and reporting on and proactively managing network and application performance," Colodny said.