My Journey in Wireless Networking: From Foundations to Expertise

What is Multi-Link Operation (MLO)?  With the introduction of the IEEE 802.11be standard (Wi-Fi 7), Multi-Link Operation (MLO) represents one of the most significant advancements in the modern Wi-Fi technology . MLO as the name signifies, allows devices to establish multiple concurrent links across different frequency bands (2.4GHz, 5GHz, and 6GHz), enabling more efficient use of available RF spectrum and significantly improving throughput, latency, and reliability. How to identifying MLO Support in a Beacon? The screenshots below shows the MLO support and capabilities in Beacon of a RUCKUS R770 AP . Let's examine the key indicators: MLO Capability Indicators In the first screenshot, we can see several critical fields that indicate MLO support: Multi-Link Control section shows basic control information with the 802.11be D3.0 tag EML Capabilities Present: True - Enhanced Multi-Link capabilities are supported MLD Capabilities Present: True - Multi-Link Device capabilitie...

 For the wireless communication, reliable data transmission is critical. Two key mechanisms that ensure this reliability are Acknowledgement (ACK) frames and Block Acknowledgement (Block ACK) frames. Let's dive deep into how these frames work and why they're essential for the Wi-Fi networks. The Fundamentals of ACK Frames ACK frames serve a dual purpose in wireless networks: Confirmation of Receipt : An ACK frame signals the sender that the frame is received. ACK could be used for data, management, or PS-Poll frame . This eliminates the need for automatic retransmission. Duration Information : For fragment bursts, the ACK frame transmits duration information to nearby Station(STAs), functioning similarly to Clear to Send (CTS) frames. ACK frame structure:  Frame Control : Contains control information for the frame (2 bytes) Duration : Specifies timing information for upcoming transmissions (2 bytes) RA (Receiver Address) : Identifies the individual MAC address of th...

In the world of wireless networking, collision avoidance is a critical challenge. Unlike wired networks where collisions can be detected, wireless networks must employ mechanisms to prevent collisions before they happen. One of the most important mechanisms in IEEE 802.11 (WiFi) networks is the Request to Send/Clear to Send (RTS/CTS) protocol. Let's dive into how this solution works and why it's essential for efficient wireless communications. The Hidden Node Problem Before understanding RTS/CTS, we need to understand the problem it solves: the hidden node problem. Imagine three wireless stations (STAs) - A, B, and C. Station-B can communicate with both A and C, but A and C are out of range of each other. If station A is transmitting to B, station C has no way of knowing this and might also try to transmit to B simultaneously, causing a collision at B. This is the "hidden node" problem - where some nodes in a network are invisible to each other but can still interfere...

 In the rapidly increasing adaption of Internet of Things (IoT), understanding  the basics network performance metrics is crucial for building reliable and efficient systems. Two fundamental metrics that play a n important role in the IOT Device communication are the Received Signal Strength Indicator (RSSI) and Link Quality Indication (LQI). Let's dive deep into what these metrics mean and why they matter for IoT implementations. Received Signal Strength Indicator (RSSI) RSSI serves as a fundamental measurement of RF power received by a wireless device. What makes RSSI particularly interesting is that it measures all RF power in a channel, regardless of the source. This means it captures: Signals from IEEE802.15.4 transmitters Interference from Bluetooth devices WiFi signals Background radiations This comprehensive measurement makes RSSI an essential tool for Clear Channel Assessment (CCA), helping devices determine if a channel is free befo...

 The ZigBee device onboarding process represents a critical workflow in IoT device management, facilitating secure and reliable connection establishment between end devices and the network infrastructure. This document outlines the systematic approach to ZigBee device onboarding:  Lets understand the Key Component of an IOT infrastructure:  End Node/End Device Represents any ZigBee-compliant IoT device, sensor, or actuator Includes various device types such as: Smart lighting systems Security devices (door locks) Environmental sensors Access Point (AP)/Gateway Comprises an embedded IoT chipset integrated into the AP Alternatively implemented as a USB module Co-ordinator (IoT Controller) Implemented as Ruckus IoT Control Manages device onboarding operations Co-ordinates MQTT traffic flow between the End notes and 3rd Party Integrations IOT Device Onboarding Process Flow Phase 1: Discovery Initiation Device Discovery State Activation Implementation varies ...

In the world of wireless network security, hiding your SSID might seem like an easy way to protect your WiFi network from unauthorized access. This approach of hiding an SSID provides a little more than a false sense of security. In my recent experience of debugging an issue with where random users could see these Hidden SSID’s, lead me to write a blog about why I personally believe it is not a great approach and I am open to opinions. Let’s explore how Hidden SSIDs Works and understand with a real world example!  When you configure your Access Points to hide the SSID/WLAN, you are essentially telling it to stop broadcasting the SSID name in the beacon frames. Under normal circumstances, An AP would periodically broadcast beacon frames containing, SSID Name, Channel, Security Capabilities etc. that helps a STA to choose among the broadcast SSID and associate to it. With Hidden SSID enabled, the AP continues to broadcast beacon frames but removes the network/SSID filed for the resp...

As a part of 802.11 Supplicant and Authenticator handshake, A STA must perform Authentication with the Access Point. This Authentication is often confused with some sort of security handshake or user authentication, which it is completely not! So what it is in reality? Operating at the link level, these frames are fundamental components of the Open System authentication method, involving a two-message exchange process that ensures proper network access control. Authentication Message Exchange: The authentication process begins when an unauthenticated and unassociated Station, generates the first authentication frame. In this initial frame, the station includes its MAC address in both the Source Address (SA) and Transmitter Address (TA) fields, while the target BSSID is specified in the Destination Address (DA) and Receiver Address (RA) fields. Wireshark Filter : "wlan.fc.type_subtype eq 11" Access point responds with a second authentication frame. This response reverses the a...