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As a leading wireless and RFID technology distributor, ScanSource is committed to providing you with comprehensive education and training on wireless and RFID technology. Learn more about the technology by choosing from the training tools below:
Wireless Discovery Checklist [Word Document]
White Papers:
Intermec White Papers
Understanding Wireless LANs:
Wireless for Beginners
Mobile Wireless Technology
Wireless LAN Q&A
Wireless LAN Glossary
Wireless Basics and General Information:
Basic Wireless Principles
Host Systems and Software
Wireless Checklist
802.11
Wireless Security
Basic Wireless Principles
The following information is designed to provide you with a basic overview of Wireless technology, including the components that make up a Wireless system and the information you need to properly configure a Wireless system. This information is solely focused on the 2.4GHz 802.11 Wireless Ethernet offerings.
The basic principles of Wireless are the same regardless of the vendor you choose. Wireless terminals (hand-held, truck mount, stationary, pen-based, laptops) send out data through the radio. Some type of identification accompanies the data so the receiving computer knows which terminal sent the data. Remember a wireless system is simply an extension to your wired system. Placing an access point on your wired system allows wireless Ethernet connection to places where wired devices may not be able to access. In simple terms, an access point receives wireless Ethernet data form wireless devices and places that information on a wired Ethernet cable.
Transport of data is accomplished in the same method as any other device attached to an Ethernet LAN using TCP\IP addressing. Since industry standards of Ethernet and TCP\IP are used, connectivity is simple when you follow standard networking principles.
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Host System and Software
There are many different types of host computers in the industry. The most commonly used in "Wireless Ethernet" systems are:
Unix Host
There are many different types of UNIX systems running various versions of UNIX. It is important to determine whether the Unix host has Ethernet TCP\IP support and can accept a telnet session. This will usually be the case with Unix systems, but there are exceptions. Most of the time the remote Wireless device will run a VT emulation program, which allows the Wireless device to appear as a wired terminal on the wired Ethernet LAN. Therefore, the remote Wireless device can access existing programs on the Unix host. This is accomplished through a telnet session from the Wireless device and the Unix host. Sometimes the remote Wireless device will have a smaller display area than the host program was written for. You will need to reduce the software application screens to adapt to the smaller display of the Wireless device. The most common method for accomplishing this involves reformatting the host application to the screen size of the Wireless device.
AS400
You can connect to an AS400 by loading 5250 emulation software in the Wireless device. The AS400 must have Ethernet and TCP/IP support along with TN5250 support. Most AS400 with version V3.51 or better have this support, but it may need to be activated. The 5250 emulation software makes the Wireless device appear as a wired terminal on the wired Ethernet LAN. This is accomplished through a telnet session from the Wireless device and the AS400. Note that the remote Wireless device will probably have a smaller display area than the host program was written for. The software application screens will need to be reduced to adapt to the smaller display of the Wireless device. The most common method of accomplishing this involves reformatting the host application to the screen size of the Wireless device.
IBM Host
You can connect to an IBM host by loading 3270 emulation software in the Wireless device. The IBM host must have Ethernet and TCP/IP support along with TN3270 support. The 3270 emulation software makes the Wireless device appear as a wired terminal on the wired Ethernet LAN. This is accomplished through a telnet session from the Wireless device and the IBM host. Note that the remote Wireless device will probably have a smaller display area than the host program was written for. The software application screens will need to be reduced to adapt to the smaller display of the Wireless device. The most common method of accomplishing this involves reformatting the host application to the screen size of the Wireless device.
Windows based PCs As the popularity and power of the PC market grows, more PCs are being used as host computers. Connectivity issues are the same as connecting to either a Unix or AS400 host, but the software issues can be more challenging. Client \ Server: In a client server software option, software will need to be written or provided for both the host computer and Wireless device. This can result in increased development time and resources. This usually requires an experienced programmer to develop the desired applications. Software Development Tools: Software tools are designed to allow users with little or no programming experience to generate software applications for their Wireless projects. Most generators are based on a GUI interface, which will be familiar to Windows users. Most generators are limited to the complexity of applications that can be generated. This should not be a problem since most Wireless applications are simple and are used to track product movements. Telnet Servers: Unlike the Unix, AS400, and IBM host, there is no PC emulation. There is a way that a Wireless device could simulate a VT terminal to allow users to access existing applications on the PC. Loading a "Telnet Server" on a Windows NT PC will allow a Wireless device, running a VT Emulation Client, to Telnet into the PC much like connecting to a Unix host. After satisfying the Login and Password fields from the Telnet Server, you can execute your software application. You'll need to purchase Telnet Servers from a third party. This is valid only with Windows NT.
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Wireless Checklist
The Wireless Checklist will help you gather the information you need to build your Wireless system using ScanSource's "Wireless Online Configurator." "Wireless Online Configurator" is an online configuration tool that builds valid systems - complete with pricing - in minutes. You will need a log-in and password to access "Wireless Online Configurator." This can be provided to you through your ScanSource Sales representative. By gathering the information on this form should help to complete a configuration using "Wireless Online Configurator."
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802.11
The IEEE 802.11 represents the first standard for WLAN products from an internationally recognized, independent organization. With this standard, wireless communication can be interoperable between vendors. This means an Intermec, Symbol, PSC, HHT, and Cisco wireless device can communicate to any other vendor products that are 802.11 compliant.
There are several offerings from the 802.11 umbrella. The following are the current offerings.
- 802.11 refers to 1 and 2 MB offerings. 802.11b refers to 11-MB offerings. This may also be referred as High Rate (HR).
- 802.11b will start at 11MB and will decrease to 5.5MB, 2MB, and 1MB if needed. Coverage range will decrease as MB increases. Special considerations will need to be made to insure constant 11MB coverage. You will need to insure a site survey is performed with specific instructions that 11MB throughput is required.
- 802.11a operates on the 5GHz frequency range rather than the 2.4Ghz range 802.11b operates at. The maximum throughput is 54MB and will decrease to 6MB as needed.
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Wireless Security
There is currently a lot of concern over security as it relates to wireless networks. It is important to note that not all wireless systems are insecure. There are two concerns related to wireless networks. The first is access to the wired infrastructure through the wireless network and the second is the interception of data as it is transmitted. There are several options, under the 802.11 specification and outside the specification, that address security issues, including WEP, access control list, and ESSID. It is important to note that a large number of wireless systems are implemented without minimum-security features.
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