My Wi-Fi is slow. Is it really the Wi-Fi?

How do your devices connect to the Internet?  How does that connection get to the information super-highway? The only way to know is to have some general understanding of how a connected device gets to the remote web site or service.

ISP service levels are sold at performance levels, bits per second.  That does not guarantee you that level of performance from your mobile devices all the way to your internet services. Your network configuration combined with your neighbors and your ISP configuration can have a real impact on your effective throughput.

People often say their wi-fi is slow when they talk about their internet experience.  Do they really mean it is wi-fi or the internet or somewhere in between?   We talked to someone in a beach neighborhood during the summer and they complained that their wi-fi was Slow.  They then said that a lot of neighbors had wi-fi problems.  These were single-family homes far enough apart that wi-fi may not have been the main issue.

Decision Tree-ish

This is my normal decision tree.  Notice that only the first two steps are easy.
  1. Does the problem go away if I plug into an Ethernet port on the modem/hub/router?
  2. Are people impacted that live too far apart to share the same wi-fi network?
  3. Everything else requires more thinking.


From Your Home to the Super-Highway

Your devices connect through your home network to the neighborhood network. The neighborhood network connects to the ISP which then connects to the Internet backbone. Large companies live on the Internet backbone often in multiple locations.  Your traffic goes from your home to the neighborhood streets to the main street (ISP) and then to the Internet.  Bad performance can be caused by issues in any of those steps.

The Wi-Fi cloud around your home

Your Wi-Fi hub/switch/router creates a radio wave cloud around your home. Any device within that cloud can use the hub to connect to the internet. Devices in that wi-fi cloud compete with each other for service and bandwidth. The more devices you have, the more conflict they have.  Video streaming services require a lot of data with low latency.  This means they create a lot of conflict for other devices resulting in worse performance for the non-streaming devices.  Hardwire devices compete for bandwidth to the street but not for wi-fi bandwidth to the hub.

Rush Hour Traffic and Sharing with Others

Internet capacity is a leased shared resource.  Your requests route across shared airwaves to shared side roads to shared main roads and eventually into a pile of requests at the service you connected to.

Wi-Fi Conflict

Your devices share the wi-fi network bandwidth of your wi-fi hub.  Your wi-fi hub shares airwaves with nearby neighbors. You take a performance hit wherever your wi-fi cloud overlaps your neighbor's wi-fi cloud. Closer neighbors mean more conflict. More active neighbors create conflict.  Conflict reduces your bandwidth. Apartment dwellers have more neighbors with more wi-fi hotspots. This results in more confect and lower performance.

Neighborhood Conflict

A neighborhood or apartment building may shares bandwidth based on the technology used in the neighborhood service. This can reduce your effective service rate. You may have to troubleshoot or dig in to understand the issue if the first two tests at the top don't isolate the problem.

ISP Capacity

Companies size and build their systems to meet expected usage with some extra for peak times and for when parts of their networks are out of service. Video games and Video streaming are huge bandwidth consumers.  Dramatic shifts in volumes in these and other services can have strong negative internet performance impacts.

Beach Traffic Example

The number of internet users in beach communities can vary an order of magnitude between the offseason and summer.  An ISP that builds out for summer traffic could be 90% idle the rest of the year. This is a significant cost for the amount of time the capacity is used. 

An ISP may decide to build to handle some percentage of peak traffic and just let the performance go down during the summer season. This means that their summer experience may be poor.  

Thus you can have someone say The Wi-Fi is slow when it is really a peak capacity issue.


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