TONY: Wireless networking uses radio frequency, or RF technology, instead of wires for the network. There are two places it can be used. One is in the office to replace the conventional wiring you’d have to put in place for a Local Area Network. The other, of course, is to allow mobile computing within the warehouse – either with hand held units, fork lift truck mounted units or, more recently, voice terminals.
PW: And what benefits does it offer?
TONY: In the office it potentially eliminates the expense of wiring up the building. In reality, the speed of wireless networking is still unlikely to be adequate for some office applications. So I would not usually recommend it as a total replacement for a wired Ethernet. It is, however, ideal for areas that are difficult to wire or for users who need the flexibility to move equipment around a lot.
In the warehouse, wireless networking is essential if you want the benefits of real-time access to IT systems from portable terminals. In particular, real-time stock information leads to improved productivity and accuracy. Moreover, this type of application typically does not require intensive network traffic and the slower speed of wireless networking is not an issue.
PW: What is needed to implement RF technology and to ensure full coverage of your premises?
TONY: You need to install wireless access points. These connect to the wired Ethernet network and then provide radio frequency coverage for the required area – sending out and receiving radio signals from the RF terminal devices in use.
To guarantee full coverage of the building your systems provider must conduct a radio frequency site survey where the radio reception is tested and the number and positioning of access points is plotted out.
PW: What if an access point fails?
TONY: To ensure you can still operate normally should any one access point fail, you must build sufficient ‘redundancy’ into the network. This means having enough access points providing overlapping areas of radio coverage so that a terminal is always within range of two different access points. Again, a good systems provider should advise you on this to ensure you get adequate resilience at a reasonable cost.
PW: There seem to be more than one type of network available?
TONY: Yes, but fortunately there are standards in wireless networking to help ensure that different manufacturers’ equipment will work together. However, the technology is evolving and there are new standards being introduced. The most common standard currently used is 802.11b, for networks operating at 11 Mbps transfer rate, although the actual transfer rates achieved tend to be less than half of this. 802.11a, strangely enough, is a more recent standard that operates at speeds up to 5 times faster, but uses a different radio frequency and equipment is therefore not compatible. Another new standard, 802.11g, should be ratified soon, and offers a similar improvement in speed. 802.11g uses the same frequency as 802.11b and therefore offers backwards compatibility.
Again, take advice from your systems provider who will be able to recommend the appropriate technology to ensure your system will stand the test of time.
PW: What about security?
TONY: Security of the wireless network is quite often overlooked and yet it’s probably the most vulnerable part of the network. You should get an expert to configure your wireless network to use encryption and other access control mechanisms, other wise you could be quite literally faced with the prospect of someone hacking in to your company network by sitting with a laptop in a car outside your building.
PW: What about cost? It all sounds expensive.
TONY: The cost has fallen significantly. These days you’re talking hundreds of pounds instead of thousands of pounds for access points, and, of course, you’re saving the cost of wiring up large areas of your building. Cost is certainly not a deterrent to using wireless networking, and warehouse applications such as Voice Directed Picking can deliver a payback in less than a year.