The City's Wireless Mesh Explained, Part one...

Recently, in one of the mail lists I subscribe to (the Austin Wireless Group), a thread was started about the new wifi mesh that's being deployed in some parts of Austin. At the time (a few months back), it received a fair amount of press about how it was going to be a public wifi network and some politicians jumped on to "associate" themselves with the new network. To some, it seemed like the politicians were promising free broadband for all Austin residents, but I'm here to tell you the real details of the mesh from someone whose been on the inside.

First, let me start out by saying that I was (am) the Lead Security Analyst/Engineer on the mesh project. A co-worker and I were responsible for the city's first efforts into wifi by designing and installing the first wifi hotspots in the city parks and most of the first wifi hotspots in city buildings a few years ago. Now, as far as the mesh is concerned, I've been to most of the technical meetings, talked to vendors and approved the security measures utilized in the system. I've got a fairly deep understanding of how this thing works, where it is, where it's going and most importantly, how you and other citizens of Austin can benefit from it.

The first thing that needs to be mentioned is the city's policy on wireless is everywhere it's deployed, it will be a public network. This was a security decision as, at the time when we first started getting the projects, wireless had some real security problems so we approached it from the flip side: Instead of trying to protect the network, we'll use our traditional remote access methods that we trust to protect the traffic. Secure the traffic, not the network. This philosophy also turns out to be beneficial to the public as now every place we install wifi, the public has yet another free hotspot. So feel free to associate and use any wifi signal you see that begins with "COA-Location" as those are the public network's SSIDs.

So now, the city has the mesh. It was born out of the need to promote the World Congress of Information Technology back in May but a savvy CIO also saw the opportunity for a longer term benefit. I wasn't in the first meetings between the CIO and Cisco but from what I understand, the city was wanting to experiment with a mesh network and Cisco was looking to promote their newest mesh system. Cisco stepped up and donated the hardware to kickoff the network by donating 55 (or thereabouts) wifi nodes, the wifi controlling system and the technical experts to get it started. Since WCIT was going to be centered around a few places in town (Austin Convention Center, City Hall, etc), the decision was made to get those areas up first and progress to the other areas of Austin soon thereafter.

At about this time, the first "myth" about the mesh was born. Because politicians were involved, some of them got overly generous with the end goals of the mesh and they led on that this mesh was going to be primarily used for providing Internet access to those people underneath the umbrella. On the technical side, we had always been told and had planned that the mesh would be for facilitating city business and be used as a testbed for future city applications but because of the network's nature (wifi), it would be a public network. The truth, as usual, is somewhere in the middle of these two uses.

It's against state law for the city to sell Internet access. You can thank your wonderful telcos and cable companies for writing the law that prohibits the city from offering Internet access like any other utility like electricity or water. So everything the city does wirelessly, the CIO goes out of his way to meet with those proprietary interests to make sure they understand what we're attempting to do and the plan won't be misunderstood. The mesh, after WCIT, will be primarily used for city business. The public will still be able to get on and use the bandwidth but that will not be its primary function. Large scale powering up of the network runs the risk of violating state law so signal output is kept low so as only to work outside (notice the name of the mesh, the "Outdoor Wireless Mesh Project." Telcos and cable companies do not provide outdoor signals so the project can't be deemed "anticompetitive." But in order to stay anticompetitive, signal strengths must stay low as to dissipate very quickly once inside buildings.)

There are numerous applications coming down the pipe at the City that might be able to leverage the wifi coverage as the connection method. As an example, one of those applications, affectionately called AMANDA, is the new building permitting system where each inspector in the field will have a tablet PC and will be able to issue permits in real time on site with no lines or waiting by the customer. Currently in their testing phase, these tablets are connecting through Cingular's HSDPA as the default transport but over time, as the mesh becomes more prevalent, we'll default the tablets to use wifi first if it exists. And since the city own's the wifi network and the backhaul, over time, this will save the city tens of thousands if not hundreds of thousands in connection costs. And you can multiply that by every new field application the city develops. The potential savings is huge.

Now, because the mesh's primary function is city business, it is being "tuned" for that business. The nodes on the mesh are running at very low signal outputs. Basically you can get a signal while standing outdoors in a clear area but once you walk into a building, the signal disspates very quickly. This is by design and not the true performance of the mesh system (I think that the mesh is only using about 10% of it's full output strength but I'll have to check on that). The point is it's not supposed to be pervasive throughout everyone's homes in the mesh umbrella zone. If you can get a signal, the city is just fine with you surfing away on it. But the city is not in the ISP business and has no obligation to "power up" the signal because it keeps dropping off in your 2nd street condo bedroom.

Personally, I think what you'll see with the mesh over time is coordination of nodes being amped up based on the applications that will be set to use them. This is pure conjecture so don't hold me to this but I can see this as a valuable way to utilize the mesh. As mentioned before, an AMANDA inspector has a few buildings within the mesh that they'll need to inspect that day. We can powerup the immediate nodes closest to those locations so the signal will propogate easily through the walls of the building and then, when the inspections are done, we can power the signal back down again. Using it in this way will allow for the inspector to easily connect to the network yet still not break any state laws for "selling" Internet access.

Another use of the mesh will be to provide ad-hoc connectivity to entities during "disaster" scenarios. Last year, when Katrina hit, the city was setting up temporary and short-term networks for the Red Cross and other national entities in city locations where those networks didn't previously exist. Now, with the mesh, we can just power up the nodes closest to the locations the groups need and there will be no need for the city to run in with the wired + wireless infrastructure that was used in Katrina's wake. That will save the city tons of money in just people power when the next disaster strikes.

In my next post, I'll attempt to discuss the city's plans for eventual mesh coverage. There's plans to roll out the mesh in some areas of Austin that have usually been left behind the technology curve so it brings into the discussion the role a municipal government has in providing Internet access to its citizens. If the discussion on the AWN list is any indication, it should be a lively topic for debate.