Compas

Microtest's Compas, a new, portable diagnostic device for Ethernet networks, makes troubleshooting a snap. Because you carry the Compas in your hand, you can quickly troubleshoot a problem anywhere on the network. A rubber housing on the unit makes it durable to protect the case from falls. And when working in poorly lit areas, you can turn on a handy backlight that illuminates the LCD monochrome display.

The Compas connects to an Ethernet network through a thin wire coaxial connector and two RJ-45 jacks at the top of the device. Two DB-9-pin, male and female RS232 connections on the bottom of the unit let you upload modules, print hardcopies of diagnostic tests, and test serial connections. Currently, the Compas supports only a 10Mbps Ethernet connection.

Testing the Compas
I tested the Compas on a Windows NT network and found many of its functions extremely helpful. For instance, I was able to ping a server, search for a Domain Name System (DNS) entry and retrieve a list of domains. I viewed the media access control (MAC) address (the hardware address of a network card, also known as the NIC). I also connected the Compas to a workstation and saw its MAC address, which verified the network card was working.

During my test for diagnosing a wiring problem, the Compas graphically displayed wire connections, showed wire length, and indicated the amount of noise on a particular wire. It even continuously blinked a hub light (using the Link Test Pulse--LTP--signal) for showing where the wire connected to the hub. This feature was useful for finding unlabeled connections that terminated 10 offices and a floor away.

For these tests, I used the Compas model that came with the Internet and NT software modules. (You can also purchase a Novell NetWare module.) To upload a module, you connect a PC to the Compas' RS232 port and then run a PC-based software program that Microtest provides. After uploading the NT software module, I searched for domain controllers, viewed the results of a Dynamic Host Configuration Protocol (DHCP) discovery, and performed a Windows NT Host Summary. It checked the DNS and Windows Internet Name Service (WINS) server lists to verify and locate a machine on the network.

Internet tests provided some of the most useful information, such as the IP Summary, which listed all the known IP addresses on the network. Other features included Duplicate IP Address detection and IP Trace Route. The IP Trace Route provided detailed routing information when I connected the Compas to a server over the Internet. This feature compiled a listing of the router paths and displayed all the IP addresses. The IP Trace Route function parallels NT's TRACERT command. (The Duplicate IP Address function serves those networks that don't have DHCP; because our network has DHCP, I did not test this feature.)

Detailing is one of the Compas' best features. It gives you a detailed summary of specific items, such as routers, protocols, servers, and hosts or clients. For instance, I detailed our Primary Domain Controller (PDC), and Compas listed all the services the PDC provided for the network.

The Compas contains a glossary of network terms, acronyms, and other helpful information. For example, while detailing PDC, I saw "MBR"--a term I didn't immediately recognize--and the Help function identified MBR as Master Browser.

More Features
Another useful feature is the error diagnostics option. By pressing DIAGNOSE, I displayed information on segment utilization, collision percentage, and error rate. When I detailed segment utilization, I saw a graphical overview of the top three users' segment utilization, and a graph of each user's donation to the general flow of network traffic. That's a feature I appreciated because this type of information usually is available only on more expensive diagnostic tools. Compas also comes with other options such as Top Talkers, Top Protocols, Top Error Sources, and Top Broadcasters, features usually associated with much more expensive tools.

Another feature I appreciated was the length of battery life. After charging the battery for only three hours, I was able to continue past the manufacturer's specified six-hour life without any trouble or signs that the battery was approaching an unusable voltage level.

I loved the Compas because it provided a handheld, powerful diagnostic tool. It is not meant to replace your expensive network monitoring software, but it is designed to augment it by providing quick, informative information about your network. Because of its price, however, I recommend Compas to only those working in large companies with widely distributed users and office functions.