LAN Under Investigation

OneTouch, the Heavyweight

The second test candidate, a OneTouch AT device from Fluke Networks, is revealed as a heavyweight when unpacked, in both the literal and figurative sense of the word. With its significantly larger color touchscreen (14.5cm diagonal, 480x640 pixels) (Figure 4), a quiet fan, and more than two pounds more electronics on board, it seriously outguns its competitor's test arsenal in both quality and quantity. However, this is also true of the price: Whereas the LanXPLORER costs around US$ 5,000 fully equipped, you can expect to pay at least US$ 10,000 for a OneTouch AT.

Figure 4: The OneTouch AT network tester by Fluke Networks. The device has a large touchscreen and needs a fan.

The OneTouch completes the basic tests just as easily as the LanXPLORER. A test button starts a number of preconfigured tests. Here, too, they start with the connection to the next switch on the LAN, and services offered there, before climbing up the ladder to Internet services. All of the tests are summarized in a score (green or red top bar). If a DHCP server is in place that only issues IP addresses to devices with a known MAC address, you need to introduce it to the network tester before you proceed to test more than just the network wiring. Alternatively, you can edit the tester's MAC address.

The first and most basic test is a test for correct wiring, open circuits, and cross-talk, as well as PoE, if used. A special end piece gives you a fairly accurate length measurement. You can find the far end of the cable using a tone generator, as with the LanXPLORER; however, the receiver (probe) is not included in the package and must be purchased as an accessory. If you have an active remote node, the negotiated link rate and the duplex mode also are displayed.

When it comes to the nearest switch, the tester detects the IP address, MAC address, and port number of the connection, provided the switch understands SNMP and the required password (community string) has been configured on the tester. You can, in principle, retrieve port statistics here, or from a neighboring gateway, but again, this requires SNMP, and a matching configuration.

Deeper Insights

In contrast to the LanEXPLORER, the candidate by Fluke Networks not only answers Yes or No to your questions relating to DNS or DHCP functionality but also provides performance data and details, such as the response time or the expiry date of the DHCP information. In the ping test, the time for the DNS lookup is shown separately, and you are given minimum, maximum, and average values for the speed of ICMP responses.

In addition to performing the simple ping test, you can access a freely configurable website, or transfer 1MB of test data to or from any FTP server. Also a Google query and mail retrieval are available as freely configurable tests. You can also check the SYN/ACK handshake with any application port. A special Veri-Fi test additionally determines the throughput, data loss, latency, and jitter of wired and wireless connections.

WLAN Included

Various details can be retrieved for WLAN connections (Figure 5), including channel utilization, signal strength, and noise of access points, or for connected clients. Using a plugged-in directional antenna provided in the package, you can even locate WLAN clients or access points.

Figure 5: An overview of a WiFi access point with details of signal strength, SSID, encryption, etc.

As with the LanXPLORER, you can add more components to the auto-test (Figure 6); however, admins enjoy more degrees of freedom here. In addition to the tests already mentioned, there are tests for various protocols, including RTSP (video), IGMP (Multicast), or SMTP (email). In a style similar to the other candidate device, a LAN view summarizes hosts, servers, printers, or VoIP remote nodes. Unfortunately, this view is not interactive, so you cannot retrieve detailed information about the devices.

Figure 6: The results of the automatic test that checked both a wired connection and a wireless LAN. The Veri-Fi test was added.

Many users probably have complained about this feature, because the vendor is now planning to upgrade it. Additionally, the overview lists "0 switches," but – strangely – the home screen lists the nearest switch and provides a detailed description. This and the failure to detect printers are all due to an incomplete SMTP configuration. However, the LanXPLORER recognized a print server without SMTP.

Fluke's OneTouch AT also has an inline mode, with which it can be looped into an existing connection. In contrast to the LanXPLORER, it can also sniff packets. However, to evaluate, you must transfer the results a storage medium and analyze with the relevant software on a PC.