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All too often we look for answers from the carrier, which provides hard-copy reports and consultation. Some service providers offer management stations and real-time reporting tools, but very few of us are buying. Those who have networks that are truly strategic know the best approach is to instrument the WAN in-house and avoid a carrier dependency trap. We brought into our Real-World Labs® four frame relay network management products: Adtran's IQ View 1.0 (beta) with TSU IQ probes, NetScout Systems' NetScout Manager Plus (NSM+) 5.2 with NetScout WAN probe, Sync Research's Envisage ControlSight and InSight 1.000 with T-FRAP, and Visual Networks' Visual UpTime 4.1.

To view the Report card.Speak of frame relay network management platforms and Visual UpTime is sure to come up. In our testing, we found UpTime to be a tactical management platform well-targeted for frame relay service level verification. But UpTime is no longer the only game in frame relay town. NetScout Systems' NSM+ is not only an excellent approach to WAN management, its capabilities extend far beyond those of UpTime as a general network management tool for any network.

Several CSU/DSU manufacturers are also offering frame relay management products, so we brought two of the most promising--IQ View and Envisage--and put them up against UpTime and NSM+. While the newcomers are good information sources and excellent CSU/DSU configuration tools, their service-level verification and diagnostic capabilities fall far short of the Visual and NetScout offerings. We also discovered the Sync Research solution to be unstable under moderately heavy traffic loads, at first losing management capabilities and then disrupting frame relay communications altogether.

Frame By Frame To test these systems (see "How We Tested Frame Relay Network Management" on page 86), we used our partner facilities at the MCI Developer's Lab, which was able to deliberately misconfigure the frame relay network at will for us. We've seen enough frame relay installations get derailed by carrier configuration errors--missized or nonexistent PVCs (Permanent Virtual Circuits), access circuit errors and excessive delay, to name just a few possibilities. We ran these platforms through the gauntlet and examined their abilities to correctly report problems, both in real time and after the fact. We also examined their abilities to monitor and analyze a broad range of IP traffic submitted to the WAN.

Frame relay places a special burden on management systems, because a single physical interface may fan out to many remote sites. From this perspective, each remote site is identified by its own DLCI (Data Link Connection Identifier), which defines a PVC end point. Each PVC may have unique bandwidth (i.e., committed information rate), priority and quality-of-service metrics, such as delay.

The NMS (network management system) must also monitor the access circuit at the physical layer--for signal drops, errored seconds, alarms, and so on. This is very important in identifying the source of trouble. Given frame relay's ability to oversubscribe the access circuit and to burst, the aggregate pipe must be monitored for overload.