Wi-Fi Connection Analysis
Ultimately, the bottom line for any network (wired or wireless) comes down to throughput performance — that is, how many bytes-per-sec can be transferred from one node on the network to another. The dBm and RSSI values that are often used in the context of wireless networks don’t mean much if you can’t somehow relate them to a performance metric. Before we can really begin to troubleshoot a wireless network we need a way to benchmark its performance, so as modifications are made we can determine whether or not they really make a difference in the network’s performance. This is where a WiFi connection analyzer comes in. It is a simple tool that allows benchmarking of one or more wireless networks.
WiFi connection analysis measures the true bandwidth between two or more devices that are connected on a wireless network — e.g. an 802.11 client adapter and an access point. When we speak of network performance, what really concerns us most is *bandwidth* or *throughput* (latency and jitter are also related). WiFi connection analysis is a technique that actually measures throughput and, hence, is the ultimate metric for quantifying performance and troubleshooting a network. And this applies to both wired and wireless networks. The output from a WiFi connection analyzer tool often includes a timecourse chart that displays maximum throughput (i.e. bytes / sec) as a function of time.
|NetSurveyor-Pro WiFi Connection Analyzer|
Compared to an RF spectrum analyzer that measures RF transmissions, or a channel analyzer that tests the availability of each WiFi channel, a connection analyzer measures the maximum available throughput between two nodes on a WiFi network — and that’s about as close as you can get to a real-world test. The main drawback with connection analysis is you need to establish a connection between two nodes on a WiFi network — either between an 802.11 client adapter and an access point, two client adapters on an ad-hoc network, or two client adapters on an infrastructure network. RF spectrum analysis and WiFi channel analysis don’t have this constraint and can be used as standalone tools.
A WiFi connection analyzer is a very useful tool that can be used in the following ways:
- To confirm, in a quantitative way, whether or not a problem truly exists with the wireless network.
- To see a measurable change in performance (either an improvement or decline) when subsequent modifications are made to the system.
- To test, concurrently, multiple WiFi networks. Multiple 802.11 adapters can be connected to the same or different access points. In this way you can directly compare the performance and reliability of different combinations of adapters and access points — not all 802.11 adapters and access points are created equal.
- To monitor the performance of a single connection — revealing whether the performance of the wireless network is impacted by RF or multipath interference or is overburdened by other 802.11 traffic.
- To optimally position the location of access points and as an aid in properly orienting antennas — by monitoring the effect on performance as you make changes to the wireless infrastructure — i.e. as a complement to a WiFi site survey.
- By reconfiguring an access point to use a different channel, a connection analyzer can help you determine which channel results in the best performance.
- To benchmark the performance and reliability of a WiFi network when first installed and at some later point in time — comparing results helps you determine whether something in the RF environment has changed that negatively impacts the performance of your wireless network.
|NetSurveyor-Pro WiFi Connection Analyzer|
When using a connection analyzer you might see the performance holding steady at a constant throughput rate — e.g. 15 Mbps. By repositioning the AP (or your laptop) you might see this change — either for the better or the worse. Or re-orienting the antennas on the AP might also have an effect. With a connection analyzer you can actually see whether changes such as these affect performance throughput. Or, the connection analyzer’s timecourse chart may show choppy throughput with large fluctuations — possibly an indication of interference from other wireless devices. The bottom line — by studying the results and graphical charts you’ll be in a much better position to determine whether or not your WiFi network is under-performing, being subjected to RF interference from other wireless devices, or performing as expected.