How to: Setup a Low-Cost Wi-Fi Mesh Hot Zone
by Jim Geier

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Many of the larger municipalities have installed or are planning to install Wi-Fi networks for creating city-wide wireless coverage. In some cases, such as Philadelphia, the coverage area is over a hundred square miles. These deployments have had ups and downs in terms of signal coverage and performance, and they are very costly. As an alternative to covering large expansive areas, some municipalities and private entities, such as home and apartment owners, are building smaller-scale Wi-Fi networks (hot zones) offering wireless Internet connectivity to smaller groups of people. This appears to be a more feasible approach. 

For example, a municipality may install a Wi-Fi network to cover a one or two mile stretch of the town’s main street, where it’s likely that businesses and the public can strongly benefit from free Internet connectivity or mobile access to the Internet. Furthermore, an apartment owner may provide coverage to tenants, or a homeowner or entrepreneur may offer Internet connectivity to a specific neighborhood. The City of Prestonsburg, KY, has done this, resulting in tremendous benefits, as explained in a Meraki case study. 

In many cases, the benefits of enabling web browsing, email and possibly voice telephony are enough to warrant the installation of a Wi-Fi hot zone. With these basic requirements, the relatively low-cost ($49 per node) Wi-Fi mesh system from Meraki is an effective solution. If widespread public safety applications require support, then you may need a much more expensive solution from other vendors, such as BelAir, Cisco, Strix, or Tropos.

Meraki system basics

Meraki offers a complete mesh network solution, which includes mesh nodes, gateways, antennas, management tools, and billing services. Meraki sells mesh nodes that install either inside a home or business (Meraki Mini) or outside (Meraki Outdoor). Both of these units act as Wi-Fi access points / repeaters that interconnect wirelessly with other nodes within range to form a mesh network. One or more of the mesh nodes operate as gateways and connect to the Internet.

Indoor nodes are very simple to install. Simply attach the unit to a window facing the street (sticky tape included), and plug the unit’s electrical cord into a nearby outlet. This is similar to indoor CPE used with traditional mesh networks, except that in the case of the Meraki system, the indoor device provides repeating and routing functions as well (thus no requirement for an outdoor node). After configuring the system through an online management console (Meraki Dashboard), the node receives its configuration automatically through the network, assuming at least one of the nodes is connected to the Internet. The Meraki Outdoor unit operates similarly, but it has weatherproofing and can be mounted on various mounting assets, such as light poles and traffic lights. For more details on Meraki’s solution, refer to the Meraki website.

Once the Meraki network is setup, a user may connect to any of the mesh nodes via Wi-Fi similar to a traditional infrastructure wireless LAN, or a user can attach to any mesh node via an Ethernet cable (unless the particular mesh node is a gateway, which has a modem cable occupying the Ethernet port). This saves many users from potentially needing to purchase a Wi-Fi card. 

Getting organized

An advantage of the Meraki solution is that it can grow organically without much planning. It’s advisable, however, to do some homework ahead of time to ensure a stable and effective system. The following are important items to consider:

Free vs. fee-based access: Determine whether network access will be free or fee-based. Meraki lets you easily configure either approach. Free service is good when marketing a particular location or area. A municipality, for example, can likely draw businesses and patrons when free Internet connectivity is available throughout the main street of a town. If installing a Meraki system in a neighborhood or apartment building for the purpose of sharing Internet services, then you should consider charging users for access. After totaling up the costs for Internet connectivity (DSL or cable service) and equipment (Meraki mesh nodes), factor in the number of potential users, and determine an equitable, or even profitable, fee to charge. More than likely, the cost for the Meraki system, including hardware and Internet connections, will be less than having each user pay for a dedicated Internet connection. This of course is the primary benefit of deploying the system. With fee-based service, you essentially become a wireless ISP (WISP), but Meraki handles the processing and management of subscriptions and payments. This makes life much easier than setting up a payment processing system yourself.

Node locations: Identify preliminary locations for mesh nodes (and gateways). With the Meraki mesh nodes, you can expect roughly 500 to 600 feet range between nodes installed along a street if line-of-site conditions exist between the nodes. My consulting company, Wireless-Nets, tested Meraki installations in both neighborhood and main street environments and found that this is a very good rule of thumb. For instance, nodes having direct line-of-sight that were 500 feet apart, with nodes installed inside windows of both facilities, an Internet speed tester indicated average 1,450 Kbps downlink speeds, which was only approximately 200 Kbps slower than connecting directly to the Internet without the mesh network. You should plan on less range, such as 300 feet or so, however, in order to have some margin for nodes that may become inoperative (e.g., if someone inadvertently unplugs one). Also, trees and other obstacles between the nodes may reduce range. You can pull up a satellite map of your area using Google Earth in order to easily measure distances and determine where it makes most sense to install the nodes. Ideally, you shouldn’t plan on installing all nodes on the same side of the street. Instead, alternate the placement on different sides of the street. That greatly increases signal propagation. 

Internet connections (backhaul): Plan on having at least one connection to the Internet. This could be as simple as using the personal Internet service that you currently have for a home or business within the coverage area. Keep in mind that shared utilization of this Internet connection may impact performance. Do some calculations to determine the impact and how many more Internet connections you might need. You’ll need to estimate the maximum number of simultaneous users and figure out the minimum throughput you want each simultaneous user to have. For example, a single Internet connection offering 1,500 Kbps would support three users at 500 Kbps each. This means that you’ll need two Internet connections if potentially supporting six users. Keep in mind that these are simultaneous users, which means that they’ll be downloading or uploading data at the same time. In reality, much of the time users are merely connected to the network and not sending anything. As a result, the system will accommodate many more users than the total that are connected to the network. With the Meraki system, you can also reduce the impact that each active user incurs on the network by reducing the maximum speed for the users to lower values, such as 100 Kbps or so, which may be okay if the service is free. Because it’s difficult to predict usage of the network, you might need to experiment a bit with getting the number of Internet connections right. 

Legal issues: This is very important. Be certain that your ISP doesn’t object to you sharing the Internet connection with others. Some ISPs have very clear language in service agreements that legally disallow sharing. If you ignore these restrictions, your ISP may notice a higher than usual traffic on your Internet connection, prompting them to investigate, terminate your service, and possibly press legal action against you. If your ISP prohibits sharing, then you may be able to upgrade to a commercial connection and avoid legal issues (always a good idea). 

Meraki Editions: Determine which Meraki Edition you plan to use use: Carrier, Pro, or Standard. Rather than explain the details of these here, you can view an Edition comparison on the Meraki website. If at all possible, try to get by with the Standard Edition, which results in much lower costing hardware. 

Installation coordination: If you’re installing indoor nodes, then contact the businesses and residents owning the facilities where you’d like to install nodes. You’ll probably have very good participation if offering free Internet access. Most owners will jump at the chance of having a node installed inside their facility because they’ll surely end up having a strong signal in addition to getting free service. The installation of outdoor nodes generally requires more coordination and expenses. When using light poles, for example, you’ll need to coordinate with the city or applicable company owning the poles. This has been very difficult and sometimes cost-prohibitive in many cases. These entities might want to charge a monthly fee for each node location, and poles may need to be converted from banked-switched power to individual light sensors to enable powering the nodes at night. Plus, you’ll need to utilize the more expensive outdoor nodes. In some cases, the municipality may need to install new poles, which gets very expensive and time consuming. If at all possible, maximize the installation of nodes indoors to avoid these problems. 

Operational support: As with any information system, you must plan on who’ll support the system and how it’ll be done. Meraki simplifies the chores of operational support by offering online statistics, error reports, centralized firmware updates, and alerts, but you’ll still need to figure out the people who’ll be responsible for making sure the network continues to operate smoothly. A municipality can take care of this by incorporating the support into existing help desk activities. With neighborhood networks, you must generally find volunteers (probably yourself) who can spend time periodically monitoring network status, such as downed or unreachable nodes, and fixing problems. 

Financing: If you’re going to offer free access, then figure out who’ll pay for the hardware and Internet connections. If Wi-Fi service is being offered along a town’s main street, the city may be willing to pay the bills, such as the case with the City of Prestonsburg, KY. If the city is not interested in financing the project, then check with non-profit organizations, such as area improvement councils and neighborhood associations. You should also consider setting up a sponsor program where businesses paying for equipment or services receive visibility on the network’s splash screen for marketing purposes. You’ll be surprised--one or two businesses in the local area may donate money for the entire network, just so they can put their name on it. 

Okay, enough of the planning stuff, let’s get down to actually implementing the network. 

Defining configuration settings

The Meraki system is easy to configure for either free or fee-based access. All configuration and management of the network is done through the Meraki Dashboard. To access the Dashboard, you need to setup a user account on the Meraki website. You’ll then be able to login to your account and configure the settings for the network.

The following are settings that you should consider before getting to far with the installation:

Public vs. private network: Meraki lets you create two separate Wi-Fi networks over the same physical hardware, with each network having a unique service set identifier (SSID). One network is the public Wi-Fi network, that you can configure for free access or establish up to two billing plans with selections for the amount you want to charge per hour, day, week or month. You can enable free trial access over a period of time (e.g., 20 minutes) along with the fee-based services. The other network is a private Wi-Fi network that provides WPA-based encryption. Thus, a municipality can have city employees connecting to the private SSID, while public users connect via the public SSID. If deploying a neighborhood Wi-Fi network, then you may want to consider having everyone connect to the private network for added security (assuming you have a trusty group, since you have to give everyone the WPA password). 

Billing and throughput: If you’re charging for access, you’ll need to enter the billing plans that you’re planning to use. In addition to the costs, you must specify the throughput provided for users. Meraki lets you identify a different performance for each billing plan. As a result, consider offering a higher throughput for users who pay more. 

Branding: You can enable a splash screen that appears when a user brings up their browser for the first time after connecting to one of the mesh nodes on your network. The Meraki system provides preprogrammed templates and a method for entering a text message and image, which results in a splash screen similar to what you’ve probably seen when logging into a Wi-Fi hotspot. This is a good place to welcome users to the network and tell them a little about what to expect (e.g., free or fee-based service), but it’s fairly limited for promoting advertisers who may be financing the network. Under the advanced menu tab in the Meraki Dashboard, however, you can configure the system to automatically redirect users from the splash screen (after subscribing) to a secondary webpage (that you create). For example, a hotel might want to redirect users to the home page of the hotel’s website, or a municipality might redirect users to a city website that identifies all businesses along the main street of the town. This secondary splash screen is good advertising real estate for those of you funding the site through sponsors and paid advertisers. 

Messaging: An interesting feature with the Meraki system is that you can enable the displaying of messages in the users’ browser tool bars. You simply enter one or more text messages, with hyperlinks to something if you want, and all users on the public network will see the message appear. If you enter more than one message, the messages rotate periodically. This can be a means of advertising. For example, you could display the message “10% off today at Jan’s Drycleaners,” for one of your advertisers (or sponsors) with a link to the business’s website. Or, a neighborhood can use it to make everyone aware of community meeting dates, soccer scores, etc.

Channel settings: You can configure the Meraki system to operate on any one of the 2.4 GHz RF channels. Based on testing that my consulting company Wireless-Nets has completed in major cities throughout the U.S., the most common RF channel in use is channel 6. As a result, set your Meraki system to either channel 1 or channel 11. It’s worthwhile, though, to run some tests first to see if existing RF interference may impact your channel selection. 

Alert settings: If you want the system to notify you in case of a downed node or other performance issue, then enter and activate an alert email address. If something goes wrong, you’ll receive a message explaining the issue. This is a good proactive approach that will hopefully lead you to solving issues before they become problems for users. 

Adding nodes: After you order and receive the mesh nodes, you must identify them in the system by indicating their serial number and MAC address (for each mesh node). This can get tedious. Luckily, Meraki has established an optional function that prompts you to enter only the order number corresponding to the purchase of the equipment, and all of the applicable nodes automatically populate into the system. In addition, you can specify a name and street address for each node. Be sure to use actual addresses where they’ll be installed because the Meraki management system will then position them correctly in an integrated Google map, which you can easily switch to satellite view. Also, think of a naming convention that allows recognition of the node by name since a lot of the Meraki reports refer to the nodes in this manner. 

Testing signal coverage

After installing the network, be certain that it’s possible to access the Internet from all user locations (where practical) and have good performance using typical client devices, such as laptops and PCs equipped with Wi-Fi radios. If low performance is found in particular locations, then consider installing additional mesh nodes to cover the holes. 

As part of the testing, create test criteria that indicate minimum levels of performance. The ability to support 1 Mbps uplink and downlink is a fairly common requirement, but you might need to throttle back performance a bit to accommodate larger groups of simultaneous users, depending on your backhaul situation. 

Concluding thoughts

Before jumping in too deep with a Meraki deployment, take some time to understand what you’re getting in to. It helps tremendously to ease into the deployment through small steps prior to plopping down large amounts of money. For example, create a user account on the Meraki site even before ordering the equipment, and see what the configuration dashboard is like. This gives you a much better understanding of what the system can and can’t do. In addition, start the installation with only a few nodes. Get that working well, and then move on to installing a larger network. 

With a little time and some trials and tribulations, you’ll have a working system up and running for very little money. 

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