Factors affecting wireless performance can be divided under 3 major categories- RF environment, AP related and client related issues.
Environment issues-
- Interference and Noise– Interference and Noise on the operating channel is one of the prominent reason affecting wireless performance resulting from reduced airtime for data transmission.
- DFS– DFS activities result in channel changes affecting performance.
- RF environment– Excessive metal surfaces in the environment often results in wireless signal absorption affecting performance if not planned properly.
- Rogue Devices– Rogue devices are one of the prominent external factors affecting wireless experience.
AP issues-
- AP locations– Positioning APs without proper wireless planning can result in coverage holes affecting wireless experience.
- AP mounting– AP mounting (direction and height) can significantly impact the radiation pattern generated by the antenna which can impact wireless performance.
- AP antennas– AP antennas (omnidirectional, directional) need to be chosen based on the requirement of the location.
- AP spatial streams and high throughput capabilities- Higher number of spatial streams and throughput capabilities can significantly improve wireless performance.
- Channel Planning– Poor channel planning can result in overlapping service areas affecting performance due to interference.
- Channel width– Statically assigned 20 MHz channel width can affect performance in high density environment.
- Roaming– Improper Wi-Fi planning can result in roaming issues.
- Lower Rates– Enabling lower rates in Wi-Fi configuration can avoid client roaming to a better AP impacting throughput.
- Higher number of WLANs– Broadcasting SSIDs occupy airtime. The optimum number of WLANs is 3 and with increase in number of WLANs the airtime allocation for data transmission goes on decreasing.
Client Issues-
- Client Capabilities– Environments typically have a mix of Wi-Fi 7/6 and legacy clients. Legacy clients operate at lower rates and end up occupying more air time affecting the performance for newer clients.
- Number of clients associated to the AP– Increased number of clients associated to one AP results in lesser airtime for each client resulting in lower throughput.
- Applications used by the clients– Too many clients simultaneously running video streams, video calls, downloading files can overload the system and cause poor experience.
- RSSI of client– How far away is the AP from the client is one the major reason for poor performance.
- Sticky client– Clients which do not roam efficiently, the client is more closer to AP A to which it wont roam to and stay associated to AP B which is far away.
- Low Power Devices– Admins often plan the environment assuming the devices will be PCs. When low power devices roam in such environments they run into coverage holes because the AP coverage overlaps were planned from PC pov.
- 2.4 GHz only devices– Scanners used in warehouses are 2.4 GHz only and low power devices at the same time. Wi-Fi planning with only 3 usable channels and ensuring there is little coverage area overlap between APs while also ensuring these low power devices do not end up in coverage holes is a tricky scenario to address.
Performance issues can be triggered due to wired side network issues as well but we will discuss that in a separate blog…
Related Blogs
Quick Reads
Why channel planning is critical?
Wireless Deployment Guides
Common Wireless Network Mistakes
High Density Wi-Fi Deployments
Educational Institute Wi-Fi Deployments
Wireless Troubleshooting
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