Ever changing environments are the biggest problem that wireless engineers face. A new site can be surveyed, and based on that, an ideal wireless design can be created for the space providing perfect signal, overlap, and SNR; the wireless engineer leaves the site, moving on to the next assignment, and that perfect design last through the weekend. Now the engineer is located in a different state, working on a different project, and is getting calls from the customer.

“Hey, we have problems, and I need you to fix them.” the customer says.
“Ok, can you describe the problem for me?” the engineer ask. Secretly, the engineer is shocked the customer is calling for any reason other than to laude the engineers talent, foresight, and general awesomeness.
“None of our customers can connect in the waiting area.” states the customer with disapproval.

Generally, troubleshooting this type of problem is straight forward. A quick look for interferers, a check to ensure all equipment is still functioning, and a general eye for anything that has changed. As a nod to the possibility of a changed environment, a simple question is asked.

“Has anything at the site changed? the engineer queries.
“Of course not” is the answer the customer provides, voice now dripping with disappointment.

Thus, the engineer continues to dig further.

Large enterprise organizations who deploy Cisco hardware generally keep maps for each facility in Cisco Prime. Smaller organizations without the budget or time to assign to Prime can find themselves looking for a different solution.

SolarWinds has a new solution that is part of NPM 11.5 and it is worth investigating. They now offer wireless heat maps. The simplicity of setting up the heat maps makes it easy for under-staffed shops to use the tool effectively. Import the floor plan, set scale, and then drag the AP’s supplied by the Cisco WLAN Controller onto the map into the correct locations. Once the AP’s are placed, the software makes a best-guess of wireless coverage. This is a standard but flawed practice.

The issue lies in physical placement of the AP’s within their environment. The AP’s are all at ceiling height, above cube walls, water features, whiteboards, and many other sources of signal degradation. The clients are on a much lower plane, and therefor see a different footprint.

SolarWinds solves this issue by allowing an engineer to place known clients on the map, and then use those to further improve the heat map. This provides a tool that can be used to understand what is happening at standard client heights, where signal matters.

“Oh look, now I see a huge null in the coverage.” the engineer says. “Are you sure there haven’t been any changes near the AP I placed by the receptionist desk?
“Oh, that’s right. We hung the sign this weekend” says the customer.
“That large metal sign that was in the shop area last week?” ask the engineer.
“Yeah, that’s the one, We suspended it from the ceiling right over the receptionist. It looks awesome. That wouldn’t cause this problem would it?”

The engineer proceeds to bang his head against the desk with a dull thud, thud, thud.
*Names have been changed to protect the identities of those responsible*

Watch SolarWinds discussing their wireless heat maps at Network Field Day 9 here: (Heat map discussion starts at 19:40)

-I participated in Network Field Day 9 as a delegate. As part of that participation, the cost of all travel and accommodations were covered. Additionally, some companies chose to give delegates small gifts for their participation. These accommodations do not in any way constitute a requirement for coverage, good or bad. In short, I am an opinionated jerk,  I was invited despite that, and anything I write is purely my own opinion. Special thanks to Tech Field Day, for the service they provide to engineers and vendors. If you would like to be a delegate at a future event, you can learn more here.