On the Air
My apologies to anyone awaiting my report on how I got on with VMware’s Server product. I’ll get back to it eventually but, in the meantime, it’s working flawlessly and I now have an opportunity to see how it performs over a longer period of time. My reason for switching topics this month is that I was presented with the opportunity to try three products aimed at wireless networking, but only for a limited time. So step aside for now VMware, and enter stage left AirMagnet Planner, AirMagnet Survey Pro and AirMagnet Laptop Analyzer. These products are aimed at organisations that either spend all their time creating wireless networks on a regular basis – conference organisers, for example – or want to know what’s happening in their established wireless networks and to be able to troubleshoot them on-the-fly.
When you install both Planner and Survey, they neatly integrate with one another, Planner effectively becoming a tool within Survey’s arsenal. It is, nevertheless, a standalone product, and an extremely powerful one at that. I’ll start off with Planner, as it’s where anyone thinking of rolling out a wireless solution should start. As I already had Planner integrated with Survey, my first steps will be slightly different from those of someone using the product on its own, but beyond that everything should be equally applicable.
I began by firing up Survey and creating a new project: you’ll need to provide a map of the area you intend to enable wirelessly, and this you can do, for example, in the form of a graphic. If you were looking to place wireless access points on one floor of an office block, you’d provide a scale map image of that floor and then tell Survey what the dimensions of the actual floor were: dimensions can be entered in both feet and metres. You also get the opportunity to enter the default power settings of your access points in milliwatts, and to choose the type of environment within which you’ll be working. This is because the project assigns certain default values, depending on what sort of activities you’re expecting to do (all values can of course be modified later), so the signal propagation assessment for a hotel or an enclosed office space will be significantly different from what would be proposed if, say, you’re working in the open air – other options include the open-plan office divided into cubicles, and a commercial offering for warehouses, shopping centres, airports and the like.
Once the project has been created, click on the Planner button on the status bar and you’ll be moved into the Planner application, which in my case was embedded into the Survey program. Once there, you can define the area you’ll be working in. You’d usually start by adding elements to define walls (brick, concrete and dry), windows (thick and thin), doors (thick and thin), cubicles, lift shafts, arbitrary areas that you can define, and more besides. The arbitrary area tool is there to enable you to lay out areas that aren’t perfect rectangles.
Items such as doors, walls and windows come with built-in default attenuation factors, so you’ll find thin windows set at 2dB and thick ones at 4dB, a brick wall at 8dB and a concrete one at 12dB, and so on. If you know, however, that your brick walls actually have an attenuation factor of 10dB, you simply lay out the wall and change that value via the wall’s Properties dialog. While items such as walls, doors and windows have an attenuation factor labelled in decibels, cubicles, dry wall offices, lift shafts and such do not: the cubicle simply shows the number 28 by default. This isn’t labelled asdB because, while it’s a sort of attenuation factor, it refers to the signal strength decrease over a whole area, whereas the values for doors, for example, show the step decrease across a single boundary.