Because full Layer 7 monitoring requires the more expensive NetScout probes, they are best deployed at central sites. These agents can monitor traffic in both directions, thus collecting application-layer detail to and from remote sites. By placing FrameSaver SLVs in remote locations and NetScout probes in the middle, very little management fidelity is lost and costs can be kept below those of comparable Visual UpTime installations.

Like most network analysis tools, NSM+ can provide an overwhelming amount of information. It's quite easy to swamp yourself with massive amounts of data, and it takes time to warm up to NetScout's four-year-old network management interface and unusual terminology. Most of the issues we had with the product were not due to limitations in its depth, but to its lack of attention specifically to frame relay. This product takes considerably more time to get running than UpTime, but it offers a much broader toolset. Fortunately, NetScout provides installation and configuration assistance as a service with the typical purchase.

NetScout promises it will eventually close the ease-of-use gap, but it made us sweat a little to get this test going. Every DLCI-specific alarm threshold and report-log setting had to be set up individually, which was cumbersome. The system properly detected DLCI changes as they occurred, yet we were forced to manually apply settings for each PVC in order to monitor the network properly. While shared "property" sets can be defined, these can't apply to specific DLCIs. We'd like to see some ability to place a default set of thresholds and trap definitions on all new circuits across multiple probes.

NetScout's major limitation during our testing was the probe insertion point, which was at the V.35 interface between the router and CSU/DSU. This kept NSM+ from detecting and isolating the T1 physical-layer problems in our tests. As noted, if the Paradyne probes had been ready for review in time for this article, we would have seen less disparity. Paradyne's Performance Wizard monitors physical- and virtual-circuit detail and serves to fill in the physical-layer and PVC-level gaps found in NetScout Manager Plus.

Visual Networks Visual UpTime v. 4.1
When it comes to ease of use, Visual UpTime is the standard by which WAN service level management point products should be measured. Because it also enjoys wide recognition and adoption by carriers, it is ahead of the pack in service level management. It's one of the few tools on which carriers and customers can agree.

Network Computing doesn't often evaluate products based on how easy they are to install and administer, yet this is the most distinguishing feature of UpTime. Its default alarm thresholds serve as a good start--they allow you to immediately start measuring the most critical aspects of the WAN, even if you don't understand every aspect of frame relay. However, we believe alarms should be thoroughly reviewed and tuned to your environment, and that trusting all defaults is not a good practice.

UpTime's Event Monitor organizes alarms by priority, more intuitively than any of the other systems we tested. Troubleshooting screens show performance graphs in real time, two-hour history or two-day history. By simply moving a time cursor into a problem region, you can quickly zoom in to a particular point in the collection history.

UpTime's canned reports are well-designed. Standard reports are geared toward the network technician who needs to monitor detailed fault and performance stats. Executive reports are aimed at the manager concerned with carrier performance and network usage profiles. Although you might expect the SQL engine to imply that standard SQL reporting tools can be used, at this point you must use Visual's toolset exclusively. It is possible to collect MIB-2, Frame Relay DTE MIB, DS-1 MIB and other SNMP data directly from the Visual probes, but history data is obviously limited in this approach. Visual is expected to announce some level of compatibility with Concord Communications' Network Health relatively soon.

While UpTime helps you understand what service the carrier is giving you, it provides scant analysis of the traffic you are offering to the WAN. Data is broken down by layer 3 protocol only, in contrast to NetScout's layer 7 analysis capabilities. For example, all IP traffic is lumped into a "TCP/IP" category, even if it's UDP. Further, you can't see a breakdown among FTP, HTTP and SMTP traffic as you can with NSM+ and even Sync Envisage. Unlike the extensive Top N Talkers available in NSM+, UpTime can display only the top five talkers in each direction.