Mesh Networking Best Practices
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Calculating the Number of APs Required
This is an important step in planning your mesh network. You will need calculate the
number of total APs (Root APs and Mesh APs) that are needed to provide adequate
coverage and performance for a given property.
Performing a site survey to determine the coverage for your particular installation
environment is essential. Once the coverage area is sufficiently covered with Root APs
to meet your bandwidth and throughput requirements, you will need to adjust the number
and placement to compensate for APs that will serve as Mesh APs.
If you plan to support Internet grade connections for casual web browsing, plan for a
design that delivers 1Mbps of throughput in the entire coverage area. For enterprise-grade
connections, plan for 10Mbps of throughput.
Wi-Fi is a shared medium, of course, so this aggregate bandwidth will be shared amongst
the concurrent users at any given time. In other words, if the network is designed to
support 10Mbps, it would support 1 user at 10Mbps, or 10 users at 1Mbps each. In
reality, due to statistical multiplexing (just like the phone system - the fact that not all
users are using the network concurrently), if you use an oversubscription ratio of 4:1,
such a network could actually support 40 users at 1Mbps.
In a Smart Mesh network, the Root AP (RAP) has all its wireless bandwidth available for
bandwidth has to be shared between the uplink and the downlink. This degrades
performance of a Mesh AP as compared to a Root. This problem is mitigated somewhat
by dual radio APs when the uplink and downlink traffic can be sent/received on two
separate radios.
Placement and Layout Considerations
• Utilize two or more RAPs: To prevent having a single point-of-failure, it is always best
to have 2 or more RAPs so that there are alternate paths back to the wired network.
• More roots are better: The more Root APs in the design, the higher the performance.
Therefore, as far as possible, try to wire as many APs as is convenient.
• Design for max 3 hops: Avoid an excessive number of hops in your mesh topology.
In general, the goal should be to have the lowest number of hops, provided other
considerations (like Signal >= 25%) are met. Limiting the number of hops to 3 or less
is best practice.
• Place a Root towards the middle of a coverage area to minimize the # hops required
to reach some MAPs.
• If there are multiple Roots, ensure that the Roots are distributed evenly throughout
the coverage area (not clumped up close together in one area). Shown in the figure
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