Overview of Wireless Site Surveys

A wireless site survey is critical to any wireless deployment with more than 1 AP. In this lesson, we’re going to be taking a look at an overview of available wireless site surveys. 

Exam Topic

1.0 Wireless Site Survey
 1.3 Perform and analyse a Layer 1 site survey
 1.4 Perform a pre-deployment site survey
 1.5 Perform a post deployment site survey
 1.6 Perform a predictive site survey 

Wireless Surveys Overview

There are a number of wireless surveys that can be completed, each with their own function. Although it might seem like additional work to complete the survey’s, each one is critical for any good wireless deployment.

The surveys that we’re going to look at are each completed at different stages within the wireless deployment process. The surveys we’ll be covering are:

  • Walk-through Survey
  • Layer 1 Sweep
  • Predictive Site Survey
  • Pre-deployment Site Survey
  • Post-deployment Site Survey

Depending on the survey being undertaken, the survey is completed either on-site or off-site.

There are a number of tools available on the market to assist when performing site surveys. Some of the main players include;

  • Ekahau
  • TamoGraph
  • AirMagnet
  • NetSpot

Although knowing the products outlined above is not a requirement for the Cisco exams. To help understand the concepts I’ll be using Ekahau to detail the step-by-step survey process.

Having been involved in countless enterprise wireless designs and deployments, for me Ekahau is by far the bet in class product currently on the market.

Walk-through Wireless Surveys

A walk-through survey is one of the surveys that is usually overlooked. The survey is completed on-site and Its key goal is to gather numerous information, including;

  • Obtaining any required digital floorplans.
  • Determine areas that require Wi-Fi coverage.
  • Determine any areas that Wi-Fi coverage is not required.
  • Areas where APs cannot be installed.
  • User behaviour.
  • Potential devices connecting to the network.
  • Understanding existing infrastructure.
  • Identify any potential areas of concern.

We’ll take a more in-depth look into walk-through site surveys in our upcoming lesson here.

Layer 1 Sweep

As the name suggests, a layer 1 sweep involves scanning the physical layer of the OSI model. This is achieved on-site by surveying the RF environment.

The main goal is to as follows;

  • Identify any non-802.11 devices.
  • Locate any potential 802.11 interference at the location

We’ll take a more in-depth look into layer 1 sweep wireless site surveys in our upcoming lesson here.

Predictive Site Survey

Predictive site surveys are the only survey that doesn’t require physical presence on site. Instead, it’s completed off-site.

The survey is completed using one of the software based tools discussed earlier in this lesson. My personal preference is to use Ekahau.

The main goal of this survey include;

  • Estimate the amount of APs required for the wireless deployment.
  • Estimate AP placement locations.

We’ll take a more in-depth look into predictive site surveys in our upcoming lesson here.

Pre-deployment Site Survey

This survey is also commonly known as APoS (AP on a Stick). Its main purpose is for validation of your predictive survey before proceeding to the deployment stage. The survey is complete on-site with the following:

  • Test AP (matching the AP used for our predictive survey).
  • Tripod (mount the AP).
  • Battery pack (power the AP).

As the name suggests, the survey involves placing a test AP in the position of each AP location from your predictive survey. The site is then surveyed to validate the results match your expectations from the predictive survey.

We’ll take a more in-depth look into pre-deployment site surveys in our upcoming lesson here.

Post-deployment Site Survey

The final survey that’s completed in the wireless deployment process is the post-deployment survey. This can be completed more than once and is completed once the wireless network has been deployed. The survey is completed on-site.

Its main aim is to verify the following;

  • Verification of network performance.
  • Identifying any potental issues.

We’ll take a more in-depth look into post-deployment site surveys in our upcoming here.