Mobile connectivity

Local hero

Wireless local area networking (WLAN), also known as WiFi, is now widely found in airports, cafes, hotels and conference centres. Research by IDC reckons that the number of such wireless ‘hotspots’ in Western European will grow to more than 32,500 by 2007, with nearly eight million regular uses.

WiFi is provided by both Internet service providers (ISPs) and mobile operators, but many mobile operators have only embraced WLAN technology reluctantly as the take-up of the facility threatens to undermine their vast investments in 3G. Most will say in public that they consider WiFi to be complementary to 3G even though 3G was originally targetted at the very same areas WLANs has now conquered.

That concern is well founded. WiFi offers maximum theoretical data rates from 11Mbps (the 802.11b standard) and up to a potential 54Mbps (802.11a and 802.11g standards). Considering that GPRS (sometimes known as 2.5G) offers a maximum data throughput of around 40Kbps and 3G, in all likelihood, will only provide an average speed in the region of 380Kbps, WiFi is easily the biggest pipe to date.


The mobile imperative

True enterprise mobility is no longer a fantasy. Analysts at research group IDC predict that the number of mobile workers at small and medium-sized enterprises alone will increase to more than 80 million in Western Europe by 2007, with a significant percentage of enterprises using ‘advanced’ mobile data solutions as part of core applications such as ERP (enterprise resource planning), CRM (customer relation- ship management) and email.

This means that IT managers need to be mapping out the connectivity options, appropriate devices, applications and middleware that will be required to satisfy that burgeoning demand for IT services beyond the organisation’s four walls.

But, while all of these areas of mobility are maturing fast, perhaps the most perplexing – and risky – is mobile connectivity. It tends to top the list of concerns that enterprises have when considering mobile solutions, primarily because of three aspects: speed, accessibility and cost.

There are several major of mobile connectivity options, each with its own pros and cons: wireless local area networks (WLANs) or WiFi; General Packet Radio Services (GPRS); and so-called ‘third-generation’ communications (3G). There are also enticing possibilities emerging with technologies such as Worldwide Interoperability for Microwave Access (WiMax).

In some cases, the capabilities of these options overlap, but organisations will often need to deploy multiple connectivity solutions in order to meet the varied and changing needs of their users.




Mixed messages

By far and away the biggest issue in WiFi connectivity is the inability of users to roam across hotspots or to switch to GPRS (and eventually 3G) technologies when they are between hotspots. This boils down to the lack of contractual agreements between competing operators, agreements that would require such things as multiple network authentication and pan-service billing.

Extensible authentication protocol (EAP) SIM cards can be used to solve the issue of roaming between competing operator hotspots. Using EAP SIMs, a user requests a connection to a wireless local area network (WLAN), which, in turn, asks for the identity of the user and then transmits that identification to an authentication server. This then establishes secure communications across all kinds of telecoms networks – in fact, this is the authentication and accounting system used by most of the world’s ISPs.

The upshot is that users don’t have to cope with different authentication passwords and bills from numerous operators, providing the subscriber with greater roaming coverage nationally and overseas, ease-of-use and one bill.

A seamless connection between GPRS and WLANs is also now possible thanks to the development of SIM-on-GPRS cards. This means that when GPRS-enabled notebook PCs come in range of WLAN hotspots, the network connection switches from GPRS to WLAN mode, giving the user the opportunity to connect to the higher performance network.

But is all this really necessary considering that it is perfectly possible to connect to the Internet at any hotspot simply by paying a fee with a credit card? Opponents of that simplistic approach argue that it still creates big security issues – issues that are overcome through the use of an EAP SIM.




State of the art?

GPRS technologies can theoretically provide ‘always on’ Internet connectivity at data rates of between 56Kbps and 114Kbps. However, a maximum data throughput is actually closer to 40Kbps.

The real star of GPRS has been the Blackberry, Research in Motion’s mobile email device, but the emerging trend among the main operators today is to offer end-users dual GPRS/WLAN cards for their laptops, which can then be used to roam between the two access technologies.

Data charges on Vodafone’s standard GPRS Mobile Connect Card are structured in such a way as to reward higher volume users with cheaper rates. Users sending/receiving 0-5MBs (megabytes) are charged EU2 per MB; 5-20MBs costs EU1.50 per MB; and 20+ MB users get each MB for EU1. Between its launch in November 2002 and the end of 2003, Vodafone sold 167,000 GPRS cards across all its markets (a relatively modest number given it has over 125 million subscribers).

Operators are pushing GPRS (2.5G) services because ubiquitous 3G is still some way off and GPRS was always intended to be the next stage on from GSM (2G). Plus, operators need to generate more cash without spending a lot of money up front and GPRS provides that. However, GPRS is an overlay of GSM technology as it uses the same time slots that carry voice traffic – slots that are at times already heavily congested.




Without bounds

With a typical data rate speed of 300kbit/sec, 3G is expected to be available in most major UK cities by the end of 2005. But businesses requiring universal coverage will have to wait considerably longer and fall back on 2.5G or even GSM services in areas that lack 3G coverage. For companies in sectors such as retailing, transport and distribution, a hybrid GPRS/3G strategy looks to be the better bet for now.

By February 2004, Vodafone was claiming its 3G networks had between 25% to 30% coverage of the company’s European licence areas. And in April, Vodafone and T-Mobile separately launched their first commercial 3G services in the UK, both based around data cards for laptop business users. Orange and O2 3G launches are slated for later this year.

Costs vary across Europe, but Vodafone’s card retails at around EU360, provided that users sign up to a data tariff package, otherwise the cost is about EU1,000.

Cost issues aside, for organisations looking to offer high bandwidth data access to remote workers equipped with laptops, 3G data cards are an attractive option. Laptop cards do not seem to suffer from the handover problems exhibited by early 3G phones, and battery life is less of a problem.

Enterprises could also give staff a 3G PC card instead of a home broadband connection. Indeed, with 3G, companies might eventually consider going totally wireless as the technology delivers performance equivalent to a DSL modem and will scale to higher rates in the future.




Out of the zone

WiMax, the three year old sister development of WiFi centred around the IEEE 802.16 standards for broadband wireless access (BWA) networks, is expected to enable multimedia applications with fast wireless connection over a whole city from a single transmitter. Early estimates suggest that WiMax should achieve data speeds of up to 144Mbps when initial implementations appear in early 2005, far greater than either WiFi and 3G.

As such it will be a cheap and easy way for organisations to deploy large wireless LANs to fixed and portable devices.

The second stage of WiMax, expected in the second half of 2005, is for ISPs and telecoms companies to deliver broadband connections to consumers through WiMax-based home access points. That will establish an alternative to ADSL and cable, not least of all because of WiMax’s vastly superior speed in the critical ‘last mile’ between the central switches and subscriber’s homes.

A third wave, still two to three years away, will be of most interest to businesses. Known as 802.16e, this part of the standard will enable a single transmitter to link to WiMax cards in computers and handheld devices over a radius of 50km, allowing banks, retail stores, cafe chains and other businesses to cover all their branches via one service.



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Ben Rossi

Ben was Vitesse Media's editorial director, leading content creation and editorial strategy across all Vitesse products, including its market-leading B2B and consumer magazines, websites, research and...

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