This chapter is from the book
This chapter is from the book
This chapter is from the book
Application Layer Features
Application layer features play a significant role in the network design, configuration, management, monitoring, and security of your wireless network.
Network Design
Many factors of network design, including terrain, distance, buildings, trees, and the presence of other networks, influence the design of your network. Sometimes, relatively expensive tools (such as spectrum analyzers) are needed to assist during the network design process. Sometimes, however, inexpensive tools are available to help you with network design.
Some wireless LAN equipment vendors include site survey utility software along with their wireless equipment. These usually display signal strength, noise level, signal-to-noise ratio (SNR), and signal quality information. Although these utilities are often designed for indoor use, they are useful to show you how well a signal from your AP is being received at different locations within your desired outdoor coverage area. These utilities are also useful for antenna alignment. Sometimes, low-cost (or free) hardware-specific utilities are available that function like a low-cost spectrum analyzer. Although these low-cost utilities do not have the full range of regular spectrum analyzer features, they do cover the entire 2.4-GHz band and show which channels are in use by other networks.
Network Management
Network management system (NMS) capabilities vary widely between different models of wireless equipment. Look for some of the following features:
Access method—Methods used to access the NMS include serial port access, telnet access, generic Windows browser access, and proprietary Windows-based software. Generic browser access is probably the easiest method to use.
Wireless link statistics—An NMS that provides statistics for each individual wireless link in a point-to-multipoint system is important to allow effective network monitoring. At a minimum, the following statistics should be available for each end user link and each AP: signal strength, noise level, and percentage of packets that need to be retransmitted.
Graphical usage statistics—Make network management easier. You can identify light or heavy traffic patterns, perform usage-based billing based on either IP or MAC address, and see when bandwidth usage peaks.
Simple Network Management Protocol (SNMP)—SNMP-based NMSs are fairly standard today. Some wireless equipment uses proprietary management software; however, many third-party management programs can manage SNMP-based systems.
Antenna-alignment utilities—Generate wireless link traffic and allow the system administrator to see real-time statistics while turning the antenna to receive the highest signal.
Flood ping capability—Floods a network with ping packet traffic. This test allows the system administrator to test the wireless link while simulating a traffic load.
Application Layer Security Features
The capability to interface with Remote Authentication Dial-In User Service (RADIUS) servers is possibly the most important Layer 7 security feature for wireless equipment.