Posts Tagged ‘site survey’

Simple Standalone Site Surveys

 

In last month’s blog we covered some of the upcoming access point features, one of which was a dedicated site survey mode on Meraki access points (APs).  We covered an introduction to wireless site survey early last year with “From Site Survey to Flawless Wireless Connectivity”, but in this post we will further examine site surveying and how to use this new feature in more detail. 

Designing a Wireless Network 

The end goal of any site survey is to ensure the most optimal configuration of the wireless network for the given requirements. These requirements can differ from physical location to physical location and can even vary within different areas of a location. Often the requirements have to be balanced against each other to reach the most optimal outcome. The requirements can include:

  • Specific support for high density or real-time applications like voice
  • Location services and positioning
  • Outdoor coverage
  • Minimization of interference with other networks or RF signals
  • Budget

Designers of wireless networks have a number of tools in their armory to meet these requirements. Some of the areas a designer can control are:

  • The location of the APs
  • The number of APs
  • The transmit power of the APs
  • The channel the APs use

Site Survey – a Designer’s Best Friend 

Due to the nature of radio waves, it can often be hard to visualise how aspects of your design will work when viewed as a collection of numbers and PDF specifications. The physical environment also has a major impact on how you design the deployment and how the APs will work. Enter the site survey and fantastic site survey tools such as Ekahau’s Site Survey and Fluke Networks AirMagnet.

These applications and others like them, allow you to visualize your WLAN deployment before, during, and after its deployment. Invisible radio waves become easy to understand with colorful heatmaps. Site surveys can be divided into three types that are typically carried out in order; predictive, pre, and post site surveys.
 

ryan_site_survey

 

Predictive surveys use floor plans, estimates of building materials, and advanced algorithms to predict how the wireless network will look. This is based on the number of APs, their location, and their configuration. 

Pre-site surveys allow the wireless designer to accurately record the reality of the physical environment where the WLAN will be deployed. This can then be used to prove, or disprove the validity of the design that is often created by a predictive site survey. The pre-site survey is typically carried out by placing an access point of the model you wish to use, with the configuration you think is appropriate, in different locations in the building. At each location the wireless is surveyed by taking readings using the site survey software. This then uses the information to update its model of the design.


tripod

Finally a post-site survey repeats the measurements taken by the pre-site survey but this time with all the APs for the final deployment in place. This survey is used to prove the design is correct or help identify adjustments that need to be made. 

Although it is not essential to carry out all types of site surveys, it is generally recommended that at a minimum, a pre-site survey is carried out for any location with more than a handful of APs. 

Listen to Ryan, a support engineer in the Meraki San Francisco office talk about the importance of surveying for your WLAN. 

 

ap.meraki.com

To perform a site survey with an AP, desired settings are typically configured before, then moving it between the locations that are being surveyed. The AP is often attached to a tripod or other type of stand to simulate the physical position it would have when deployed e.g. wall mounted or ceiling mounted. To make the movement of the AP easier, it is not normally attached to AC power and is instead powered by a portable battery pack. 

Before the introduction of the dedicated site survey mode on the Meraki APs, it was necessary to include an additional equipment beyond just power. The reason for this was that the self healing auto mesh functionality built into every Meraki AP would try and repair the AP’s connection to the LAN. It does this by scanning for other mesh APs to communicate with when it can’t see a gateway. When this happened, it meant that site survey tools were not able get a reading. 

The new site survey mode allows network admins to turn an AP into a dedicated device for site surveys. When enabled the AP will broadcast an open SSID named “site_survey-” followed by its MAC address. The AP can then have the channels and transmit power set for both 2.4Ghz and 5Ghz radios. 

To access the site survey mode, wirelessly connect to the desired AP and enter ap.meraki.com into your web browser. Alternatively you can access the same page by entering the LAN IP address of the AP into your web browser.

local_status_page

This local management page on the AP is used for basic setup, troubleshooting, or for when a specific manual configuration is required. Choose the ‘Configure’ tab and enter the credentials requested by the login box. Once logged in, you can access the settings for the site survey mode.

local_site_survey_mode

Summary 

Completing a site survey is often an essential step on the path to an efficient, high performance WLAN. Ensuring your deployment is right from the start can save many hours of troubleshooting and associated costs later on. The new Meraki site survey mode will help make this process simpler and easier for anyone going through this activity.

 

Presenting the Meraki WiFi Stumbler, a new free tool for troubleshooting, optimizing and planning wireless deployments

Note: This post has been archived for historical purposes and no longer contains accurate information about our current products. If you would like to learn more about Cisco Meraki and our cloud-managed IT solutions, including wireless APs, switches, security appliances, security cameras, and unified endpoint management, please check out the Meraki products page.


Update: the Cisco Meraki WiFi Stumbler is now available only for Android devices. Find it on Google Play.

Today we are very excited to announce the release of a new free tool for the IT community: the Meraki WiFi Stumbler, the first browser-based wireless scanner.  WiFi Stumbler provides detailed, real-time and continuously updated information about nearby wireless networks (even those with hidden SSIDs), including the type of access point, MAC address, wireless channel, signal strength, encryption type and more.  It also features built-in search, sorting and filtering capabilities to make it easy to quickly find the data that you need when in the field troubleshooting networks.

So what is cool about the fact that it runs in a browser?  This means that there is no need to download and install software, making it a very convenient tool that can you can quickly have up and running whenever you need it.  WiFi Stumbler will run in most browsers on either a PC or a Mac, and it can even be used when you are not connected to the Internet if your browser supports HTML5 offline mode (currently only Firefox 3.5, but Safari and Chrome support should follow soon as well).

You can use WiFi Stumbler to optimize coverage and performance of existing networks, troubleshoot wireless performance issues, find rogue APs and perform basic site surveys when planning deployments.

The Stumbler web page has the same clean, intuitive feel as the Meraki Dashboard that our customers have come to expect from our products.  Here is a screenshot:

Stumbler screen shot

We will be adding new features and functionality to Stumbler on an ongoing basis – these features will be available to all users as soon as they are released.  And since the tool is browser-based, there is no need to download and install the latest version of software, or add patches or software updates to get these features.  Just reload the tool in your browser and the updates will “magically” appear.

Check out http://meraki.com/tools/stumbler for more details and to try it out.  WiFi Stumbler is still in beta release, so if you find any bugs or have any suggestions for new features please let us know using the Wish box in the tool.

We hope you find this to be a useful addition to your toolkit!

-Posted by Greg Williams