The LANMeter is not a replacement for a protocol analyzer, and it is an expensive upgrade from a basic cable tester. However, the benefits of switch and router field diagnostics displace some of the cost. And while it's not a substitute for second-level support, the LANMeter empowers your cabling team to troubleshoot further into the network. This product supports 10- and 100-Mbps Ethernet, as well as 4-Mbps and 16-Mbps token-ring networks. A scaled down version, the 683 Enterprise LANMeter, supports only 10- and 100-Mbps Ethernet networks.

Beneath the Surface After unpacking the LANMeter, I plugged it into the production network at the university. Since our network is set up for DHCP, I instructed the LANMeter to obtain an IP address on the local segment, which it executed perfectly. If your network doesn't run DHCP, you can enter an address manually.

The LANMeter is an effective first-step diagnostic tool; it enables IT to diagnose network problems and determine if they are physical or hub-, NIC- or OS-related. The LANMeter provides complete protocol information on packets going through the network without compromising security--it never displays or decodes packets on the user screen.

After I configured the LANMeter for our network, I selected the segment discovery option. The LANMeter examined our network and discovered routers, switches, active subnets, DNS servers, SNMP agents and other hosts. It actively polls routers, switches and workstations for IP and interface configuration information and device descriptions. It catalogs all of the hosts on your network by device type, so you can later surf through the menus and examine the hosts you're trying to troubleshoot.

The LANMeter also checks every device for proper configuration, including duplicate IP addresses, incorrect subnet masks and improper network addresses. To my surprise, it found a half-dozen incorrectly configured IP address masks, several duplicate IP addresses and a handful of switches with IP addresses from a different network.

I decided to investigate some of the product's included advanced options. I selected the router menu from the segment discovery summary. The LANMeter provides a listing of all routers found on the local subnet. I pointed the LANMeter at a Cisco 2500 frame relay router. Thanks to the SwitchWizard add-on software, a new menu for switches and routers appears, letting you dig into the hardware and obtain SNMP and RMON information from selected devices. I particularly liked the multiport statistics menu within the SwitchWizard add-on. This feature graphs utilization of all the interfaces on the switch or router and lets you drill down into individual interfaces.

When diagnosing switches and routers, you also can examine route tables and ARP (Address Resolution Protocol) tables. As for monitoring your network's health, there are definitely more cost-effective ways to poll switch and router utilization information than with the LANMeter. In the field, however, having the handheld ability to plug into a switch and check error statistics is quite useful.

Getting Physical At the physical layer, the LANMeter is a full-fledged diagnostic tool capable of scanning cables for faults, improper wiring and attenuation. An optional remote add-on lets you verify cable quality, while another add-on lets you test fiber-optic cabling. A built-in capability analyzes a NIC or a hub for possible physical problems. You also can insert the LANMeter inline between a workstation and a hub to diagnose inline problems, such as poor signal strength from a NIC or hub.

In addition to physical troubleshooting, the LANMeter also provides Layer 3 functionality. It offers all of the basic connectivity tests that a notebook PC would provide, including IP ping and trace route functionality, IPX ping, server list and NetWare get-nearest-server processing. Using the LANMeter's Internet Toolkit--part of the SwitchWizard add-on--you can use SNMP and RMON queries to explore beyond the local subnet without running to another closet.

The LANMeter also includes a new Web-based remote agent. By enabling the agent, a manager in the field can communicate diagnostic information to remote support personnel. This feature lets remote users view the LANMeter's console, but doesn't enable remote control of the device. Fluke suggests that service personnel use this feature to notify senior IT staff members of possible problems, since they can view the problems in real-time on their Web browser. Unfortunately, the display currently doesn't let you operate the LANMeter remotely.

Joel Conover can be reached at jconover@nwc.com.