Last week, in our blog series on how to plan a cloud-managed wireless mesh network with CloudTrax and why, we looked at the key elements of building a strong wireless network: Bandwidth, Access Points and Enclosures (Click Here). This week we’ll give you a few tips on how to plan your node placements and how many nodes you require for your unique needs.
Determining the placement and number of nodes needed
Quick Tip: Let CloudTrax do the work
For large installs, test your environment with CloudTrax and two or three nodes. You’ll be able to see the range and how many walls and floors you can expect to transmit through.
The number of nodes you require depends on five factors:
- The size of the area you need to cover.
- How many walls and floors you need to penetrate with mesh.
- The material of the walls and floors you need to penetrate.
- The amount of interference in your environment.
- The number of simultaneous users expected on the network.
While every installation is different and the number of nodes you need will vary greatly with the factors above, in general, you shouldn’t exceed these parameters when planning:
|Device||Indoor range||Outdoor range||Max walls to penetrate|
Benefits of using CloudTrax to determine placement and number of nodes:
- In CloudTrax, you’ll be able to see the speed of each device and signal strength between devices (both of which decrease over distance and through walls and floors). Look for a signal strength (or “RSSI”) of at least 20, where 30+ is desirable. You can add, remove, or reposition nodes as needed at any time.
- While Open-Mesh has tested more than 250 users on a single node in the lab, you should aim for no more than 20-50 users per node to give each user an optimal experience. The maximum number of users will vary based on your network environment, ISP connection, and bandwidth to each client device.
- With any model, it is possible to overpower dense indoor networks. However, you can turn the transmit power down through CloudTrax if you experience symptoms such as interference or dropped connections. Setting TX Power to 19 or 21 dBm typically resolves these issues.
- For large installs, test your environment with CloudTrax and two or three nodes before buying all of the nodes. You’ll be able to see the range and how many walls and floors you can expect to transmit through in your specific environment. Nodes transmit in a spherical pattern—up, down and side to side—so there’s no need to “aim” signals.
Here are some guidelines to help plan how many nodes are needed for your installation
Nodes: indoors or out?
With the advent of low cost mesh technology, network design is literally turning “outside-in.” Here are some benefits of installing your nodes indoors:
- It is much less expensive to install inside rather than outside
- Outdoor nodes often require an electrician to install power
- Outdoor nodes often involve getting up on ladders or rooftops
- Outdoor nodes require installation of long Ethernet cables
- Outdoor nodes can be unsightly and often violate apartment/ condo CC&Rs
- Outdoor nodes take your strongest signals outdoors, the opposite of what you generally want
Typical number of nodes needed according to application:
Hotels and apartments: You will typically need one node for every four to six hotel rooms or apartments. This will vary depending upon the type of construction and layout. If you are in a single-story, single-row concrete/ brick/stone build, you may need one node in every second or third unit. For wood frame, multi-storey buildings with interior hallways and small rooms, one node for every six or seven rooms may be sufficient if placed in a central hallway.
When installing multi-storey buildings, we recommend placing units on every second floor for both concrete and wood buildings. Copper ceilings, steel plating, cement and adobe-type materials may limit (and even eliminate) signal transmission between floors.
Coffee shops and restaurants: One well-placed node can usually cover an entire coffee shop. For restaurants or large coffee shops, you may need two or three nodes, especially if you want to cover outdoor seating areas.
Small and medium-sized businesses: One well-placed node can usually cover a small retail shop. For larger spaces, use the numbers in the table above to plan the number of access points based on the number of walls to penetrate.
Residential neighbourhoods: In residential neighbourhoods, we recommend that each house has at least one node. And if the houses are especially large, you can add multiple nodes to the house to provide better coverage in every room. Wherever possible, place nodes near windows or exterior walls with a direct line of sight to the nodes in other houses. Placing some nodes outside may help extend coverage more efficiently.
Quick Tip: Test with a smartphone
Smartphones are the perfect device for testing. First, they are by far the most popular device on networks today. Second, they have a much weaker antenna than a laptop, so you’ll be able to find holes and weak spots in your network faster. A simple speed test application can show your download and upload speeds in each area of your property.
Determining a location for your gateway(s)
Gateway Users on mesh networks will lose half—or more—of their maximum speed for every hop they are away from a gateway. Therefore, you want to place the gateway(s) as central to the area you want to cover as possible. As you can see below, forcing traffic through too many hops quickly leads to very slow network speeds.
By moving the gateway from one end to the centre, as shown below, you can improve the maximum potential speed on the outer reaches of the network by a multiple of four.
If most of your repeaters have a direct (or single “hop”) connection to the gateway, their speed is maximized. The easiest way to accomplish this is to put your DSL/cable/fibre connection as close to the middle of the area you want to cover as possible.
Quick Tip: Using RSSI to position nodes
From the Access Points map view in CloudTrax, click on any node to see its name, throughput and connection to other nodes.
All of your nodes should have an RSSI of at least -70 (the closer to zero the stronger the signal) to one or more nodes. If not, try repositioning them closer or add more nodes.