Rosedale Ridge

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In December 2012, The FNF and Connecting for Good built a network for the residents of the Rosedale Ridge housing project in Kansas City, Kansas. This page serves to document that build.

Geography

The Rosedale Ridge housing development sits on an elevated ridge 3.7 miles from the Central Business District of Kansas City, MO. The RR complex sits at 290 Meters above sea level at 39.06420664858759N,-94.62955713272095W - and the buildings are approximately 10 Meters in height. From the northernmost buidling of the complex, there is a small window in the foliage that allows for clear line of sight to Oak Tower, one of the two major on-net buildings in Kansas City, and home to the first production FreedomLink. The base of Oak Tower sits at 280 Meters above sea level at 39.10110855731589N,-94.57875609397888W - with our site on the 27th story adding approximately 90 Meters to that elevation.

Bill of Materials

All of the materials used to build the system are available off the shelf, through vendors such as l-com and baltic networks. Prices given are per unit, unless otherwise specified. Materials:

  • 1 x Supermicro 2u server
  • 2 x Ubiquiti Rocket M5
  • 2 x Ubiquiti Rocket Dish 5, 30dBi
  • 1 x Pyle Ultimate Support Speaker Stand
  • 1 x Standard Non-penetrating Roof Mount
  • 1 x 1.5"x10' EMT Conduit
  • 6 x Cinderblocks
  • 4 x Meraki
  • 4 x Weatherproof enclosure
  • Cat5 Cable
  • Zipties

Tools:

  • 40ft ladder
  • Drill + bits
  • Ethernet crimp tools
  • Adjustable wrench

Configuration

The configuration of the Rosedale Ridge network represents a fairly standard DIY network design pattern. In this particular case, four mesh repeaters communicate with one another while also acting as access points for residents. One of the mesh nodes is connected by wire to a radio equipped with a high-gain directional dish. A matching radio/dish combination some distance away is connected by wire to a router, which is in turn connected to an upstream provider.

The Mesh

In this particular case, the mesh/access network was built using some donated/repurposed meraki gear. It's not ideal, because it doesn't give us the freedom to improve the system, and will be remotely disabled by meraki in a couple of years (so that they can get folks to buy more hardware). Regardless, it was what we could procure with a highly limited budget. The configuration of the mesh repeaters was extremely simple, essentially using system defaults except for changing the SSID. Libre tools designed to do the same job would do well to emulate the meraki gear in this particular regard: sane defaults, works out of the box.

Point-to-Point

The distribution/middle-mile portion of the network consisted of of a pair of Ubiquiti Rocket M5's, each equipped with a 30dBi MIMO dish antenna. The radios were running AirOS, which is built on OpenWRT. The Media access scheme employed was a TDMA protocol designed by ubiquiti, called airmax. Both radios were configured to accept a dhcp lease from the router, act as layer 3 bridges, use the same SSID, and to use WPA2-AES256 encryption over the air. The Oak Tower radio was configured as an access point, and the Rosedale Ridge one as a station. The devices were locked together using MAC address binding, aligned by sight, and then by signal level.

Routing

For our edge router, we were able to procure a surplus 2u x86 supermicro server. We installed pfSense, a bsd distribution, for combined firewall/router functionality. The router was configured for a static address on the WAN interface, and to act as a dhcp server on the LAN. Stateful firewalling and NAT allows LAN clients out to the internet, but does not allow incoming connections.

Results

With rough alignment of the radio elements and a not-quite-clear line of sight, we were able to accomplish better than 30megabits of duplex connectivity between the two sites. To achieve the same result using an incumbent carrier for distribution, we would have had to pay $350/month. Our colocation cost for the routers and radio at Oak Tower is $125/month. We will recoup the cost of the point-to-point gear in just over two months, and save $225 per month thereafter. most importantly: the residents of Rosedale Ridge have Internet access in their homes - most of them for the first time.