Over the weekend I was at the [BIL conference]http://www.bilconference.com, a barcamp/unconference style justaposition on the very expensive TED conference. I gave a few talks, including one on self driving cars, privacy and AI issues.

The conference, being free, was at a small community center. This location did not have internet. Various methods were possible to provide internet. The easiest are routers which can take cellular network EVDO cards and offer an 802.11 access point. That works most places, but is not able to handle many people, and may or may not violate some terms of service. However, in just about all these locations there are locations very nearby with broadband internet which can be used, including hotels, businesses and even some private homes. But how to get the access in quickly?

What would be useful would be an "instant internet kit" with all you need to take an internet connection (or two) a modest distance over wireless. This kit would be packed up and available via courier to events that want internet access on just a couple of days notice.

What would you put in the kit? In some cases, there will be a wireless network available that can be reliably "seen" already by a directional antenna appropriately placed at the temporary location. So some people could make do with just the destination equipment. This would be a parabolic antenna with tripod mount and pole clamp, with wire to run to a weatherproofed wireless device that can operate in "client mode," ie. become a client of any ordinary access point. This client mode radio might work on 802.11a (which is less used) or on 802.11n.

This device would also have in it a second, omnidirectional antenna set and an ordinary 802.11b/g access point. This would provide access at the target location, if having the AP outside is suitable. It may also be necessary to move the AP inside. In that case there are three options.

1. Have a long antenna cable from this unit up to where the directional antenna is, and accept losses on the cable.
2. Don't use the access point equipment, and instead plug an ethernet wire into the unit, and run that ethernet wire down to where the access point or points are to be. Cheap access points are plentiful and need not come in the kit, though they could. If you want to have several that all connect, you might want to do that.
3. Do a triple wireless link, with repeater wireless boxes in the target rooms which are able to get a link to the rooftop box over wireless, and repeat it within the rooms.

With just one of these units, you would take the client unit up onto your high location, aim it at your source by plugging a laptop into the unit and using a web console designed for site survey, aiming and entry of parameters like SSID, encryption keys etc. Depending on your relation with the source, you might have this endpoint get an IP address from the source and do NAT, often resulting in double-NAT.

Another option in the kit would be to add a source box. This would go at the location where an internet connection is available. Ideally this would plug into the source network using ethernet, and either act as an access point to the target box, or speak a bridge or ad-hoc protocol with it. It would have another parabolic dish antenna plugged into it for this purpose. It would come pre-configured to match the target box so the two can be paired together with minimal configuration for a nice encrypted link. The source box should also be able to do the natting, though you don't want both source and target box to do it, you want only one, and ideally none of the boxes to do this.

The source box would also have on it or with it a second radio with small directional antenna to use in client mode if the source is also only available in wireless form. This may be the case in hotel rooms, or commonly if you want to do this on a roof of a building that already has a wireless net. For long wireless links, there is no substitute for height.

In some situations you would just plunk two boxes on two roofs, aim the antennas, set the SSID for the client on the source box and be ready to go.

Now you can get all these things off the shelf today, and in fact they are not even that expensive. The kit would include higher end equipment, but since it is only being rented for a few days, it need not be very costly to rent.

Power

If you want to be on rooftops, they may not be power. If you just run an antenna cord, that can solve the problem, but for quick set-up there is merit to just being able to put the box anywhere that has the best line of sight. For temporary connections battery power on rooftops may make sense. Many access points draw only a few watts. If the boxes are ready to take 12 volts, that means you can run them for several days on a car/marine/rv battery, which many people have on hand. You could also offer in the kit an external battery pack with sufficient power. With two battery packs, it would also be possible to simply swap the batteries once or twice a day if that's easier than running up an extension cord. Many locations may not need access at night, in which case a single small battery could do the trick. External laptop batteries that provide 16 volts with over 100 watt-hours can be had for about $100 on eBay and don't weigh very much.

In some cases one of these points might end up on the roof of a car, truck or RV. In that case, 12 volt power from the vehicle could do the job. Fortunately today it is easy to get devices that can power on a range of voltages from 11 volts to 24 volts, allowing the use of just about any battery or power supply.

A slightly more expensive version of the boxes might use a form of power over ethernet to deliver the power to the rooftop boxes. PoE access points are now readily available. Since most customers would not have a PoE hub, some PoE injectors could be included with the kit for those who will be running ethernet wire up to their box.

Packages

I would expect a company providing this to offer a variety of kits. One kit would have just a target box. One would have both a source and target box. Add-ons would provide internal repeater boxes. A "complete" kit would throw in batteries, ethernet wire and 12 volt battery clamp-on cables for use with car batteries, or a cigarette lighter adapter. A really complete kit could involve masts and strips but you can get those locally in almost all cases.

Multiplexing

To provide a really fast connection, it is also possible to combine several connections. A more advanced kit would be able to draw from multiple sources, and possibly even combine them with connections from wireless broadband cards. There are several ways to combine connections. These include tunnels which reassemble all the streams at a remote network server so it all looks like one network, or a round-robin server that assigns the traffic from different internal IPs to different routes.