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Community Wireless

Internet access in bulk, delivered to a location with good fiber connectivity, has become amazingly cheap. Retail Internet access remains comparatively expensive because of the costs of distributing that bandwidth to individual homes and businesses. But wireless technology has now advanced to the point where it is possible to deliver high-speed, always-on Internet connectivity without building a costly "last mile" infrastructure. Using unlicensed, freely available radio frequencies, Internet access becomes so cheap that it can be provided for free, as a public service.

We envision a partnership between municipal governments and non-profit organizations to build a city-wide, wireless backbone.

The system is based on three tiers. Tier 1 nodes will generally be located on municipal property, and be owned and operated by the Internet Archive. Tier 2 nodes will often be on private property, usually owned by private parties, but managed remotely by the Internet Archive. Tier 3 nodes are always owned by individuals, can be managed by them. They will usually come pre-configured to easy setup.

The Internet Archive provides:

• Free and fast Internet bandwidth
• Radios, antennas, switches and routers for tier 1 sites
• Configuration, management and monitoring of the network
• Training for installers

The city provides:

• Access to roof-tops of tall buildings
• Access to radio towers
• Access to fiber optic cables
• Installation of radios and antennas

Companies, non-profits or individuals become tier 2 sites by:

• Buying an antenna kit
• Mounting the antenna kit on their roof

End-users:

• Depending on their distance to a tier 2 site, might need to purchase a window-mounted device (tier 3).

Tier 1: Backbone sites with fiber, city-owned

These are best located at high-elevation buildings or radio towers with good line of sight in all directions. Ideally municipal fiber is available at these sites. While direct end-user access can be provided at tier 1 sites, their main purpose is to provide point-to-multi-point access to tier 2 sites. If no fiber is available, a point-to-point link to another tier 1 sites may have to suffice. All radios on neighboring tier 1 nodes are synchronized to listen and talk in the same microsecond rhythm, which reduces interference between tier 1 sites and makes the most efficient use of unlicensed radio frequencies. Each tier 1 site can feed about 60-80 tier 2 sites.

Hardware:

• Three to four 90- or 120-degree sector antennas, each powered by GPS-timed 5 GHz radios.
• Three 120-degree sector antennas, each powered by 2.4 GHz radios.
• Managed switch

Tier 2: Building without fiber, crowd-sourced

A tier 2 node is typically located on the roof of a building, which might be an apartment or office building, or even a single-family home. Unobstructed line-of-sight to a tier 1 node is required. A tier 2 node connects to a tier 1 node on 5 GHz and provides a 2.4 GHz open, directional WiFi cloud. Anyone who is close enough can connect directly to a tier 2 node with any suitable device (such as a laptop or smart phone). However, particularly indoors or at a greater distance, access through a tier 3 device is recommended. Each tier 2 site can feed about 25 tier 3 devices.

Hardware:

• 5 GHz dish antenna with built-in radio
• 2.4 GHz flat-panel antenna with built-in radio.

Tier 3: End-users, crowd-sourced

A tier 3 node is a single device that brings the outdoor signal from a tier 2 device inside, on a wire. Ideally, the device should be mounted on a roof, but window installation with a suction cup is an option where the signal is strong enough. Line of sight to a tier 2 site is usually required.

Hardware:

• 2.4 GHz flat-panel antenna with built-in radio.