Moblogging Jokkmokk 2004

Since I have had very little time to blog about the technical parts involved in this project, I thought that it would be suitable to mention something about it at this point. I will here summarize the work with the wireless LAN put up in Jokkmokk.

In order to prepare for the rest of the blogging team I set off from Ume? on Wednesday with the 6:00 am bus. With me I brought wireless access points, cables, a pocket PC and a tablet PC. I arrived in Jokkmokk seven hours later at 1:00 pm. I there met with the people from Jokkmokks IT-department.

With the access points that were provided (3 Cisco AP:s, 2 Intel and 4 D-link) it is not possible to cover the entire market area. A few areas with a lot of activity had instead been picked out to become so-called hotspots where files could be uploaded and downloaded. Jokkmokks IT department provided us with several network connection points. After investigating the area along with Andreas from the IT-department we started building the net.

The first net was located in and around the tourist office. This was thought to be a got point since it?s in the heart of the market area with market streets on all sides. The tourist office is also a very natural place to visit now and then to warm up in cold weather. The building is made of wood which is easier to penetrate with radio than for example concrete. Two points were placed on each side of the building.

The second network located at the museum became the most difficult to set up. The point where we could get access to the network was placed in a nearby building meaning that a link had to be established across an inner yard. I started by using a directional antenna for this purpose. The building seamed to have some serious damping effect on the signal so I was instantly forced to reinforce the link with several repeaters. But even then the link could only be maintained during short periods. After having tried every possible configuration and placement of access points and antennas I had to give it up for the day. The bad experiences continued the next day and I soon started to suspect some source of interference.

In a previous experience with setting up a wireless LAN I observed a similar problem. That time the range of the access points was seriously reduced. The cause proved to be an RF video link causing interference. That time problem could easily be solved by changing the radio channel in use. This time however changing the channel did not seem to have any affect which I think indicated a spread spectrum source of interference. After a great deal of work the link through the inner yard was made up of mostly cable with only a few short jumps of wireless radio. The good news was that once I got into the museum main building the interference seamed to disappear. Still the network could sometimes be unreachable due to changing interference on the link in the yard.

Network number three was put up in our market office. This installation took no more that ten minutes, once we had solved the problem of finding the right key for the premises. A forth network was available at the school were the concert on Saturday night was to be held. Since the school already had a wireless network the only work here involved strengthening the network just before the concert. We needed a really good network in this case so that the streaming client not accidentally would disconnect from the streaming server in Ume?.

Numerous conclusions could be made from the Jokkmokk experience with regard to wireless lan. One that we immediately made was that the hot spots we put up would only give us good coverage during day time. In the evenings the market activities moved away from the, during day time, most densely populated areas.

As far as the equipment goes my opinion is that far too much time went into configuring the devices. I would guess that there in the future will be wireless equipment available that specialises on the kind of temporary networks we were building here. Such equipment would perhaps have simple buttons on then to configure them as client, repeater or access points. They could perhaps also have features such as battery packs for power supply on places where no regular power could be found.

Of the different brands of access points that were available I would rate the Dlink as the number one for building temporary wireless network. The Dlink:s got the same flexibility at for example the Cisco AP?s but when it comes to fast configuring they are superior. The Intel AP?s are easy to configure as well but lack the abilities to configure the device as repeater or client. Intel AP?s also makes a lot of noise which made them unfit for placing in for example the museum library. If you also consider the price of the equipment the Dlink equipment gains even more points. You could get ten Dlink AP?s for the price of one Cisco AP. That means that I could have gotten as many as thirty Dlink AP?s, instead of the three Cisco AP?s I brought. In temporary wireless networks there is often a greater risk of theft since you have less time hide the equipment in temporary installations. With cheaper equipment the risk of theft as well as the loss from theft will be less.