Wi-Fi

How did Wi-Fi evolve? In 1997 we were introduced to a new technology – Wi-Fi, or to be more specific IEEE 802.11 standard. Demand for better performance and reliability forced the standardization authority i.e. IEEE to release amendments to the initial standard. At the beginning, these amendments were denoted as single letter appended to the […]

The 802.11ax brings important features, focusing on network capacity, latency and range. High data rates are still in the picture, but rather in the background. Introducing OFDMA and using MU-MIMO allows AP to schedule data for multiple users simultaneously. This way, latency can be greatly decreased. With the new colors of the channels, frequencies can be spatially reused.

This post discusses selected practical aspects of Wi-Fi systems including: explanation of some parameters and factors that the network performance is impacted by; showing how to configure some of the parameters them using CISCO Wireless LAN Controller; presenting simulated scenarios to show some examples of radio measurements.

Introduction to Wi-Fi Security Distributing data using wireless medium means that anyone can capture the signal. There is no boundary, like in case of cable communication, which prevents unwanted access. This means we must take other security measures. In this blogpost we will review current algorithms providing Wi-Fi security and we will take a sneak […]

The problem, network components and topology I recently faced the issue with AP join to vWLC. Cisco 2700 AP could not join to newly installed Cisco vWLC controller. Coleague asked me to take a look and explained the topology. The vWLC was located in Grandmetric DC Testing Labs whereas Cisco CAP-2700 was located at Grandmetric […]

Introduction First Wi-Fi networks appeared in late 90s and many of us use them ever since. During these years we could observe significant increase of throughput, but what is important, it is not only due to the ISP providing better link. Wi-Fi standard also evolved to keep up with the higher throughputs. If there will […]

Introduction Communication between devices is often discussed on link level, which means that the focus is on how two end points exchange information: what is the protocol, waveform, timing in sending messages etc. This however, does not take into account that there are other devices wanting to use the medium. Using the same medium by […]

After discussing the main wireless transmission concept (How wireless works?), main channel propagation phenomena (What is pathloss? and What is shadowing?), and antenna configurations (What is MIMO?), let’s now take a look at one of the most commonly used transmission scheme nowadays, namely Orthogonal Frequency Division Multiplexing (OFDM). But, before we explain why do we […]

The time has come to present our youngest initiative, a training course that binds together the two worlds – “Wireless” and “Networking”. Why this training is different? This unique course combines the theoretical foundations for the wireless transmission and Wireless LAN standards, together with the practical aspects ranging from measurement, planning and troubleshooting activities, to […]

WiFi has been considered as an offload mechanism since the introduction of LTE in 3GPP Rel-8. However, the initial inter-working between the two Radio Access Technologies (RATs) was very loose, with WiFi connected to the Evolved Packet Core (EPC) with the help of add-on functions (such as ANDSF hidden deep in the network) making suggestions for […]