Rogue Access Points (APs) can be set up innocently or with malicious intent. They can cause interference with your WiFi network, present vulnerabilities to security, and have devices on your network connect to it instead. Whether it's a part of WiFi Health Checks or security analysis and monitoring, it's always a good idea to know how to physically locate these rogue Access Points.
Active WiFi Survey
An active WiFi survey is when a surveying device is connected to the WiFi network and records signal measurements based on the performance of the connection. Active surveys are used to troubleshoot WiFi networks. This type of survey also allows for various other metrics to be measured, such as ping round-trip-time (RTT), throughput using iPerf/iPerf2/iPerf3, and Internet upload/downloads.
Vital signs are measurements of the body's most basic functions. When a body is not performing well, vital signs, such as body temperature, pulse rate, respiration rate, and blood pressure, are used to monitor and detect potential medical problems.
Similarly, if your WiFi network is not performing well, the following “vital signs” can be checked to determine the health of a WiFi network.
- Signal Coverage
- Signal-to-Noise Ratio
- Channel Overlap
- Rogues and Interferers
- Access Point Placement Optimization
When I first started in networking back in the late 1990s we called outsourced management of customer owned or leased equipment a managed network service (MNS). The scope of these MNS projects could range from just remote management and monitoring of routers to full turnkey design, installation, and management of all IT assets (routers, switches, servers, firewalls, etc.).
A typical WiFi deployment project plan can be divided into four stages: requirements gathering, WiFi site design, configuration & installation, and service turn up & acceptance.
When planning a WiFi project one of the first questions people typically have is related to how many access points they will need. To provide the best possible answer the following information is needed.
- Coverage area / floor plan
- Shape of area / floor plan
- Building / wall material
- Number of users
- Capacity/Throughput requirements per user / application
iPerf is an open source software utility available for many operating systems. iPerf3 is used to measures the available TCP and UDP bandwidth along a path between two hosts and can be used for wired and wireless testing.
When using iPerf there is usually a sender/client (iPerf -c ) and a receiver/server (iPerf -s).
This setup involves measurement/survey software running on a laptop or tablet that can collect information about WiFi and non WiFi devices in the environment. This data is compared with WiFi signals from a temporary access point deployed for this survey process positioned at locations we believe would meet the requirements of the deployment.
iPhone and iPad users with iOS 7 and up, now have a way to view WiFi scan info (SSID, BSSID, RSSI, Channel) on devices with Apple's AirPort Utility app. Prior to this AirPort Utility update, only SSID and BSSID information was available on app store apps (non jailbreak apps).