The business case for wireless networking is becoming harder to ignore as workers, unleashed to roam around the premises or the nation with full network access, deliver measurable productivity gains.

The case for the wireless LAN has stumbled along for almost a decade, suffering from distance and throughput constraints, standards uncertainty and management and security issues. It went through a pre- boom period in 2000 but a general downturn in the market and serious security flaws put the dampeners on.

Since the end of 2004 security has largely been sorted, and while management issues now top the list of user concerns, there a greater willingness to adopt wireless as a mainstream adjunct to the wired network.

"Wireless is now doable, secure and manageable but has to be done properly. If you do it badly it becomes insecure, unmanageable, unreliable, and can fall apart in a screaming heap so you’ll never go back to it again," says Cisco consulting engineer Arron Scott.

Research company IDC after a 2005 survey said wireless LANs are expected to grow 33 per cent a year for the next 5-years. And while fat or stand alone access points peaked in sales last year and are expected to decline slightly this year, controller-based access points for centrally managed wireless networks are expected to grow at greater than 33 per cent a year.

Some suggest the business case for wireless is elusive but that depends how you look at it. In the manufacturing and retail sectors it’s simply good logic to throw off the curse of cables. This frees users in warehouses for example, with bar code and RFID scanners and handheld inventory devices, to keep track of pallets coming in from suppliers and track items all the way to the retail shelves.

In the office the business case is less obvious and based around intangibles such as freedom, mobility and empowerment, with executives, mobile workers or workgroups having flexibility to operate beyond personalised desktops. In some case there’s no other option – running cables into a heritage building or a temporary premises may be impossible, and rather than knocking down walls to locate cables wireless may simply be the path of least resistance.

Wireless is perfect for hospitals, universities, hotels and premises where management and project teams need to get around. If there’s a wireless node in the boardroom, classroom, laboratory or lobby there’s no reason why anyone should have to race back to their desk to get important documentation.

The payback comes from better productivity and a more informed workforce. "Those who are able to access their emails and have essential information on the move are more informed at meetings and more likely to share that information," says Scott.

Jason Hurlbut, global vice president of development Siemen’s HiPath wireless networking product range, says the idea of productivity gains from wireless is no longer the question, "the question is whose wireless do I get".

He quotes a study of US enterprises showing the main business drivers are improving productivity and corporate agility and becoming more flexible and faster communicators. "Wireless achieves both. Its not that you do more in the same time it’s just that you have access to all the information all the time."

While only about five per cent of companies are asking for voice over wireless currently, in the next two years Hurlbut believes that’ll skyrocket to 95 per cent. "They see this as part of the converged environment including IP telephony and want their mobile or wireless phones to do this. Most of the major manufacturers have announced hybrid devices that do both GSM and Wifi."

As far as the return on investment goes Paull Wilson consulting engineer with Hewlett Packard says the cost of deploying a wireless network compared to a wired network is minimal - a couple of hundred dollars for the hardware and another couple hundred more for access points. "Once the network is up and running you can easily add people with little additional cost."

He says SMEs with less than 30 employees are rapidly deploying wireless because it allows them to expand their workforce and more easily engage contractors without having to make an investment in desks and cables.

From a strategic management point of view he says the trend is to encourage wireless use where it makes sense; for on-line net meetings, sharing files on the move and presentations.

However central management is becoming increasingly important to ensure optimum performance, greater security and to get around bottlenecks.

Hewlett Packard uses wireless LAN technology to create flexibility for those travelling inter- company or inter office. The management system recognises each user wherever they log in and ensures they’re up to date with the ID key which changes regularly for security purposes.

When placed into its correct context, security becomes simply another one of the ‘silos’ that sits under management. While not the big turn-off it once was, vigilance remains essential. In the past, IEEE 802.11 wireless developers have been forced to make tradeoffs between security, interoperability, and affordability which at times have been mutually exclusive. The arrival of the 80211i standard for wireless security has bought a new level of confidence.

"It’s something you need to regularly monitor. You don’t just put it in and leave it," says Wilson. There’s a need to regularly review management protocols and look for rogue access, which may put the overall network at risk.

Standards have matured

HP works with Bluesocket, Cisco and others or deploys its own ProCurve tools, an indication of the trend toward partnership in the industry. "Customers don’t really care who it comes from as long as it works. The standards have matured a lot. For example many notebooks now encompass 802.11a, b and g all e and the flexibility extends to access points working with PDAs and smartphones."

Kurt Brandon, managing director of Kalooma warns security implemented on its own can in fact become an impediment. "If you focus too much on security the laptop gets so locked down you can’t even leave the desk which kind of defeats the purpose."

When you can centrally control the network there’s less need to nail things down. Wireless LANs are a broadcast, spread spectrum medium, which operate mainly in the 2.4GHz and 5GHz range and "shout out" to let you know they’re there. "If your wireless network suddenly stops working you need to know why."

Wireless LANs need to be fine tuned and maintained by people with the right skills. A well conceived system puts security in its proper place, as part of a centralised management system. This requires a good understanding of the differences between the various 802.11 standards, how radio frequency and channelling works, how to set up the access points so the signal doesn’t go bouncing off the walls and how to manage devices, applications, users and performance and prioritise for voice.

Wireless 802.11 networks are not designed like cellular networks which can ‘talk’ to three cell sites at once, know when to hand off, when to bounce and when there’s load on the network. Managing VoIP to laptops over wireless handsets requires a management gateway so voice gets voice full priority and clarity.

If you can manage the actual radio frequency you can also know where the network devices are, improve control over user access, and facilitate fast hand-off and switching between access points. Most access points and switch vendors have protocols or proprietary approaches to help with that.

Sniffing out rogues

Kalooma represents Bluesocket gateways which connect to the equipment and devices of most vendors, managing bandwidth, security and roaming across VLANS. The devices are used in a number of larger networks including Parliament buildings, Te Papa museum, McDonalds, Deloittes and St Kentergens and St Cuthberts schools.

Kalooma also uses the Air Magnet product listens in to the network to sniff out legitimate devices and detect overcrowding or interference. "If you have a dozen access points and someone else builds a network next door and floods your network space you need to see what’s happening."

This is critical for example if you are using wireless for credit card transactions and need to show an audit path between devices and access points that hasn’t been touched from outside.

In larger networks such devices are often interfaced with a SNMP network management suite such as HP’s OpenView or Computer Associates UniCentre.

Jason Hurlbut from Siemens says the most important step a business can make, ahead of installing a wireless LAN, is to invest in a site survey. "In addition to knowing what applications will be run on the wireless network a survey will determine the RF absorption characteristics of walls and other barriers to determine where to install the access points.

A decade ago wireless was all about ‘fat access points’ for a common area but in the past three years there’s been a move to controller-based systems to deliver enterprise mobility. For most equipment suppliers scaling a wireless network beyond about 20 access points is complex and costly. "Because all the capabilities are typically in the access points they cost more and it can become a management nightmare," says Hurlbut.

A centrally controlled wireless LAN makes it easier to plan, install, manage and optimise. If you remove authentication from the access point and place it with the controller, this frees them to hand off more quickly and enables easier roaming with less latency.

He expects VoIP on wireless networks to grow in the same way wireless LANs did when Intel and other included wireless chipsets in laptops. The trick though is to ensure your network is able to prioritise voice from the access point. "Most of the centrally controlled systems have thin access points which are little more than smart radios and are unable to provide quality of service prioritisation."

Siemens HiPoint gets around this because it is an IP layer 3 solution and its access points have some intelligence in them allowing voice to be prioritised. The ‘fit’ access points are poised between ‘fat’ and ‘thin’, enabling quality of service and encryption to be done at the edge of the network and configuration and authorisation centrally. The central controller acts more as a router than a switch and access points are added through a plug and play approach.

"This means we don’t have to take into account the underlying physical network or create VLANs to expand. Once installed it cheaper to run and less challenging on resources than some rival offerings," says Hurlbut.

"It makes it easier to plan and gives seamless mobility, including voice roaming across access points and subnets without dropping a call. You maintain your IP address so you don’t have to do all this hand shaking," he says.

Currently you can boost the capability of networks by using smaller additional radio cells but for most people wireless is simply ad-hoc network access for web browsing and Citrix thin client. You would never put printers or file servers on a wireless network and it will never be a replacement for 100Mbit/sec dedicated Ethernet in most environments, says Cisco’s Arron Scott.

While the hype suggests wireless networks can deliver up to 100Mbit/sec, that doesn’t pan out in reality. Scott says actual speed today is still 5-25Mbit/sec. The fundamental design dictates that when others share the network, speeds reduce. In fact collision avoidance technology prevents any current wireless network operating at 100 percent – it’s more realistically 50 per cent use.

Even with next generation 802.11n which promises 300Mbit/sec capabilities real world speeds are more likely to be 100-150Mbit/sec, says Scott. And Jason Hurlbut from Siemens suggests the Mobile WiMax 802.16b wireless standard, on the brink of ratification, will make 802.11n irrelevant, largely because its being supported by Intel which plans to deliver new laptop chipsets. While it could be three years away from mainstream use it could become a wireless LAN alternative much quicker.

Wider model ahead

HP’s Paull Wilson agrees Mobile WiMax could seriously challenge the status quo as SMEs look for ways to expand their wireless coverage into public spaces including courtyards, campuses and out to coffee bars, which will only add value to the business model.

"A real estate agent may meet a client at Starbucks and take advantage of the 15 minutes free internet access to scroll through the options on the web, or a mobile worker could link back to the company’s systems using a virtual private network tunnel for security and performance."

Wilson was in San Francisco in October when the mayor agreed to put a WiMax mesh network in the CBD free of charge for all the residents. "It’s always risky talking about a roadmap going forward but it looks a lot clearer than it did two years ago. WiMax is a reality and a lot of wireless LANs are now going to be connected into a much bigger footprint."

He says WiMax presents opportunities and challenges. "It will challenge mobile networks and 3G broadband which are too expensive here in New Zealand. It will also being some competitiveness that’s why Telecom has bought its wi-fi into its mobile business as they can see the potential threat and the opportunities which they want to be abreast of."

It’s axiomatic that technology changes, sometimes in ways we can’t predict. Why would you build a RF network that only connects laptops and PCs when the trend is to incorporate a growing menagerie of portable and handheld devices? Would you only build for low level data when bandwidth rich applications and voice may be part of the mix in the next couple of years?

Wireless should be an enabler that is transparent to the user, not something that costs more to manage than it does to install. And you don’t want to get caught in the crossfire as emerging standards and leave less efficient approaches behind in the dust. Plan to meet today’s needs and those of the foreseeable future but keep the doors open to embrace and upgrade when the technology, the business case, the cost and the timing is right.

With wi-fi in the home and hotspots springing up all around the globe, executive and mobile workers are gaining insights into a new era of affordable, unfettered on-demand communications.

With next generation offerings looming the concept of the wireless local area network will have less to do with the defined office space and more to do with securing and embracing the available network wherever you are.

ends