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A 32-bit Windows95/98 and Windows NT 4 application, Mentor is not a protocol analyzer but a software-only solution that attempts to make sense of network traffic across the wire. It features a multilevel graphical user interface with wizards for beginners that can be switched off for more experienced users.

Mentor also analyzes TCP/IP, IPX and LLC (Logical Link Control) on the LAN, and token-ring and frame relay on the WAN. When used in conjunction with a Wandel & Goltermann Domino protocol analyzer, Mentor analyzes multiple segments in real time.

Wandel & Goltermann's product enhances the expert analysis process, appealing to the experienced network manager who now has a tool that bridges and expands upon the network diagnostic expertise of his or her network engineers.

Interactive Instructor When I tested a beta version in Network Computing's Real-World Labs® at Syracuse University, Mentor's default cookbook wizard popped up, asking inane questions like, "Are users complaining of dropped packets?"

As annoyingly obvious as this type of question can be for the experienced troubleshooter, the process does establish a diagnostic procedure, as it documents the state of change on the network and leads directly to the complaint.

This very interactive approach not only helps the novice attack a problem systematically, but lets advanced network engineers save their troubleshooting procedures, facilitating consistent network analysis. Mentor saves these procedures as steps that are exportable and importable for easy population using standard Windows file and network access.

To get to the guts of the product, I opted to turn off the wizard and loaded a Network Associates Sniffer capture file extracted from a 100-Mbps segment, which served the Internet to the 8,000 nodes on campus. Besides supporting Wandel & Goltermann Domino protocol analyzers for real-time capture, Mentor reads Sniffer compressed or uncompressed capture files.

Once Mentor sucked in the Sniffer capture file, it looked similar to Sniffer and Internet Advisor expert capabilities. In the lab, Mentor identified single-packet problems, like CRC (cyclic redundancy check) errors, as well as the more complex interpacket diagnosis of retransmissions and duplicate IP addresses. This product measures over 20 thresholds, pointing out network violations as well as noting what parts of the network are working properly.

The final step in Mentor's diagnostic procedure is the suggestion of possible solutions. During testing, Mentor offered "check wiring" and "CRC errors can lead to data corruption," which were obvious--but accurate--conclusions for my limited tests. It is Mentor's methodical yet thorough approach, along with the flexibility to skip novice wizards, that makes it a winning product.

Bruce Boardman can be reached at bboardman@nwc.com.