Product Reviews

Handheld cable and network testers are ideal tools for support staff as they can quickly find faults that could otherwise take days to diagnose and solve. Fluke is a company that has had a long association with testing equipment and offers a comprehensive range of products including digital and automotive multimeters and electrical testers. The NetTool is the latest addition to its network tester family and combines cable, network and PC configuration testing facilities that aim to solve the majority of connectivity problems.

The NetTool is a compact little plastic box that fits snugly in the palm and weighs only 210g empty or 310g with four AA batteries installed. You can use alkaline or rechargeable NiMH batteries, and Fluke also offers an optional AC power adaptor. On each side are RJ-45 ports that support 10BaseT and 100BaseTX links, and which can also be used to identify 4/16Mbits/sec token ring and phone connections. Each port is also partnered with a pair of multifunction LEDs. One shows link pulse, collisions or errors while the second changes colour to show different levels of link utilisation. The top half of the NetTool fascia is taken up by a backlit LCD panel with menu navigation buttons and a Power button below.

The NetTool comes in two versions - single-ended and inline. The basic model supports single-ended operations where only one end of a network cable is connected to either of its RJ-45 ports. This mode can be used to check for a network connection, confirm an active device is at the other end and display its operating speed and duplex mode. The inline version can be placed between two network devices so it can test the connection for faults and provide performance details.

I found the NetTool extremely easy to use. You only get one menu option after power on which initiates an Autotest function that analyses whatever the NetTool is connected to. Cable testing is simple as you just connect one end to the NetTool, press the Select button and it will display an icon for the NetTool and a cable spool to represent

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an open connection. Select the Spool icon to see cable status and length. Any split pairs, shorts or opens will also be highlighted. If you have access to both ends of the cable, plug them both into the NetTool for a wire map diagram. This shows whether you have a straight-through or crossover cable and displays each end of the cable, how the pins are connected and any detected faults. For longer cable runs, Fluke provides a wiremap adaptor which connects to one end, although I found this was unable to accurately measure cable lengths under 15m.

Large buildings will almost certainly have some unidentified wall sockets and the NetTool can quickly ascertain their purpose. Just connect it to the socket using a short length of CAT 5 cable, select Autotest and it will tell you whether the socket is connected to an Ethernet or token ring network, or is an RJ-45 phone connector. For the latter, the NetTool isn't designed to test telephone networks but merely to detect their presence. If it's an active Ethernet port, NetTool will discover and display all detected services including IP, email, Web and NetWare servers. For the latter it can display the nearest file server, time synchronisation servers, NDS servers and management servers. It will also pick up routers and network printers for an in-depth picture of the world beyond the wall socket.

The NetTool can be connected to a PC's network card for link testing and it will show the speeds and duplex modes available and those negotiated plus link level and polarity. If it spots a swap cable problem, the NetTool will rectify this internally so you can carry on troubleshooting over this. With the inline mode activated, the NetTool can be placed in between devices for a more in-depth analysis. A health view in the form of two speedometer dials can be used to view any pairing of link utilisation, collisions, broadcast frames and errors.

The NetTool also has a jack plug on the side for connecting it directly to a PC using the supplied serial cable. With Fluke's NetTool Blaster software installed, you can access the NetTool for downloading new software revisions or upgrading it swiftly from single-ended into the full inline version. A handy Screen Grabber tool also lets you download the current screen on the NetTool as a bitmap.

Traditionally, network testers and analysers have always been on the expensive side and the NetTool is no exception with the inline version costing £1,042. However, its remarkably compact chassis does offer a high level of cable and network testing facilities and will undoubtedly prove an invaluable companion for network support staff.