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Site surveys have slowy been changing over the last year and half. I'm not saying that site surveys aren't needed, not at all, but the processes wrapped around them are changing. For example, with solutions that offer dynamic RF monitoring and adjustment, partners have the option of either doing the site survey before the deployment or concurrent with the deployment. Let me explain further with an example.

While there are other vendors who do dynamic RF adjustment, the one I know well is, of course, Cisco Airespace. "Auto-RF" is the name Airespace gives to dynamic RF adjustments and monitoring. Auto-RF is accomplished through a process called Radio Resource Monitoring (RRM). With Airespace, some partners are bypassing the site survey and installing a grid pattern of APs in the customer's environment. Once the APs are deployed and initially configured, the partner uses the Airespace Controller Web GUI interface or Wireless Control System (WCS) to view the network environment. Auto-RF is employed to make dynamic adjustments to AP channel and power settings, with the controller, or multiple controllers working together, determining optimum coverage for the entire location. Changes to the environment are constantly monitored and periodic adjustments are made when necessary.

Both the Controller Web and WCS allow you to view the current state of the WLAN and APs. In addition, you are able to view "coverage holes" or areas of low or no RF coverage. In this situation, either Auto-RF would increase power to surrounding APs to alleviate the coverage hole or the partner could choose to install additional APs.

The tradeoff here is that the customer doesn't have to pay for a site survey before deployment begins but that additional costs may be required during the actual deployment due to unforeseen circumstances. What we're finding is that many partners will come in before deploying to determine what problems may exist (using spectrum analyzers and other Wi-Fi analysis tools) and incorporate those expectations into the estimated cost of the deployment. The partner doesn't do a full-blown site survey but still has a good idea of what to expect as the deployment commences.

As this relates to DFS and TPC, solutions that are already doing dynamic adjustments will be better able to incorporate 802.11h requirements because they'll have already been doing that anyway. 802.11h will just formalize and standardize the process.

Joel

Joel,

This is a fantastic post my friend. You bring up very good points that I think everyone should really consider...

1) Site surveys are becoming limited to spectral analysis - looking for interference
2) Deploying APs in a grid format, subsequently allowing the system to format and periodically calibrate the RF environment
3) Deployment hangups are dealt with on an as-encountered basis.

This approach makes site surveying a snap.

Devinator

Thanks Joelb,
Very interesting!

AWESOME POST Joel. Thanks a million for passing along this info.