Evaluating Readiness to Support Wireless LANs

Evaluating Readiness to Support Wireless LANs

By CWNP On 08/09/2007 - 33 Comments

Make certain you have solid support plans, including knowledgeable staff and the correct tools, before you give a thumbs up for that new wireless network.

By Eric Geier

Many companies hire third-party solution providers in order to deploy a wireless LAN in their facility even though internal staff may be extremely knowledgeable in wired networks, gained from experience in deploying and supporting their existing Ethernet network. Although a solution provider may implement a precisely designed and installed wireless LAN, you’ll likely run into complete chaos if you aren’t prepared to support it. Proper training and familiarity for those who are going to be tasked with supporting and ensuring the security of the new Wi-Fi network is vital.

This tutorial concentrates on the evaluation of your current technical support system to see how ready you are and what you may need to do before deeming the new wireless network operational.

When preparing your support plan for your wireless LAN, consider areas such as:

• Education and experience
• Management and support tools
• Support structure
• Polices
• Back-up plans
• Technical coordination

This part of the tutorial covers the first two bulleted items shown above; a later tutorial will cover the remaining items.

Education and Experience

Although your current network or PC support staff may have vast knowledge of networking, wireless LANs introduce many other aspects and fundamentals which are typically lacked in those who have a traditional wired networking background.

You should poll your support teams to gain an understanding of their tech skills and knowledge to ensure they are educated in areas such as:

• Introduction to wireless LANs - Your help desk, desktop support, and especially any network support teams should have knowledge such as understanding themain components and basic operation of a wireless LAN and the ability to compare and contrast the 802.11 standards, which instills most people with some common sense when dealing with wireless networks.
• Wireless LAN administration and troubleshooting - The knowledge of the individuals intended to administer and support the wireless network should include (but not limited to) installing, configuring, and securing client radios and access points, knowledge of RF fundamentals and 802.11 network architecture, performing RF site surveys, and understanding Wi-Fi security issues.
• Wireless LAN security - The security or network support team should have an extensive understanding of Wi-Fi security, including intrusion tools and techniques, technologies such as 802.1X/EAP, VLAN-based security solutions, 802.11i, and Authentication, Authorization, and Accounting (AAA) Systems.
• 802.11 packet analysis - Understanding how 802.11 devices communicate, such as the exchange of packets during the authentication and association process, how a network reacts to power saving clients, and understanding the data within the packets can greatly help when troubleshooting issues on the wireless network.
• Vendor specific hardware training - Those who are going to be installing and configuring the wireless infrastructure equipment should have a great deal of prior hands-on experience to ensure seamless support when your wireless LAN is operational.

If more training is required you may want to take the opportunity to have the support teams earn related certifications such as through the Certified Wireless Network Professional (CWNP) and Cisco Career Certification programs.

While throwing a few books at the support teams may provide great knowledge, many IT professionals need a bit more hands-on training through live training courses. However if live training is out of your budget, you may want to look into eLearning or computer based training (CBT) courses which typically provide video lectures and demonstrations. You could also gather some extra wireless networking gear for them to play around with to get some hands-on experience before the network is operational.

Don’t forget about all the resources you have online, such as the insightful tutorials and articles on Wi-FiPlanet.com.

Management and Support Tools

Properly supporting and troubleshooting wireless LANs typically requires adding a few new tools to your arsenal. If you haven’t already acquired them in the design and installation phases, before going operational, you may want to consider purchasing several tools:

• Wireless network management and monitoring tools with features including:
  • Support for multi-vendor APs
  • Rouge AP detection
  • Configurable security policies
  • Alerts
  • Network health monitoring (such as throughput and excessive packet retries)
  • Monitoring of RF conditions (for instance interference from neighboring networks and other 2.4 or 5GHz devices)
  • Ability to remotely manage the network (including changing security, channel, and SSID settings and updating firmware)
• 802.11 packet analyzer - Among a few other things, this tool enables you to “see” what is actually happening over the airwaves to aid in troubleshooting performance or connectivity issues with your Wi-Fi network or devices.
• RF Spectrum analyzer - Spectrum analyzers give you a better picture of the RF environment to help identify and find devices interfering with your Wireless LAN. Even though other tools such as a packet analyzer may give you some of these features, a spectrum analyzer will provide much more detail of the RF environment.
• Wireless LAN surveying tool - Though usually not a necessity, Wi-Fi surveying software provides a usefully graphic representation of your wireless network coverage layered on a digital floor plan you import. With the software’s simulation features these tools can aid in detecting coverage holes and may provide predicted coverage maps when considering the movement of APs and the changing of other characteristics, such as channel assignments, transmit power, and antenna type.

You may want to look into the software suites and hardware tools of vendors such as AirMagnet and Berkeley Varitronics Systems. In addition, make sure the support staff has a solid understanding of the tools you choose before making your wireless LAN operational.

Support Structure

Your support structure should be modified to adapt to new problems and fixes brought up when having a wireless LAN. You should define how and what issues, related to the wireless LAN, are distributed to each support team. You may also want to create or acquire flow charts or fault isolation trees to help identify how to response to and troubleshoot wireless networking performance and connectivity issues.

Here are many common issues you may run into:

• Unable to establish a connection to the WLAN
• Experiencing intermittent connections
• Poor performance
• RF interference from rouge APs or neighboring networks

You should keep these in mind when creating troubleshooting flow charts or when thinking about the structure of your help desk and support teams.

Create New Policies

To ensure the security of your new wireless LAN, you should create a few new policies, such as:

• WLAN Operation Policy - This policy may require anyone installing access points (APs) to first have approval from a designated IT group and specific installation and configuration guidelines. In addition, the policy may strictly forbid the connection of unauthorized APs to the corporate network.
• Internal Wireless User Policy - This policy would define the rules and policies of using the wireless LAN by employees and staff, such as the restrictions of use and support information.
• Public Wireless User Policy- If public access is given you should create a user policy to inform users of the support you can provide and restrictions of the network’s use.

Create Back-Up Plans

Wireless LANs communicate via radio waves, thus adding another potentially problematic element to the mix when compared with wired networks your company may already have installed. Additional problems wireless LANs face include RF interference from other wireless networks, interference from other non-Wi-Fi devices using the same frequency band, and intentional interference commonly termed as Denial of Service. In addition, the RF environment constantly changes. For example the movement of people throughout the facility, the weather (in some cases), and changes in the building structure or office arraignments may affect the RF environment.

Due to the potential for failure (such as the examples described above) you should plan what to do if the wireless network becomes unusable. For example, you may want to ensure all vital systems using the WLAN has an accessible connection to a wired Ethernet network for use when the wireless LAN isn’t operational. Furthermore, carefully consider the dependence of critical systems or vital operations on your wireless LAN.

Coordinate Requirements

Ensure the network support team understands the defined expectations and baseline standards of the wireless network, such as:

• Signal-noise ratio
• Throughput
• Packet retries
• Intended coverage areas

Therefore administrators and technicians have an idea of the required and typical attributes of the WLAN which can help when performing testing and troubleshooting.

Further Support Readiness Evaluation

In addition to taking the items discussed in these two tutorials under consideration, you may want to get outside help such as from an experienced consulting firm. Having an evaluation of your specific situation (based upon your current network, support structure, and specific wireless technologies) will provide detailed feedback on your readiness to support a wireless network and how to resolve any issues.

Eric Geier is an author of many wireless networking and computing books, including Wi-Fi Hotspots: Setting up Public Wireless Internet Access published by Cisco Press and 100 Things You Need to Know about Upgrading to Windows Vista published by Que.

Blog Disclaimer: The opinions expressed within these blog posts are solely the author’s and do not reflect the opinions and beliefs of the Certitrek, CWNP or its affiliates.