Too many standards spoil wireless LAN soup

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Customers eager to move to a 5GHz wireless LAN environment are facing a fast networks market splintered by multiple standards. 

A single wireless LAN standard for the 5GHz band — instead of three different standards, 802.11a, 802.11h and HiperLAN2 — would allow products for the 54Mbit/s networks to work everywhere. It would also lower costs because chipmakers, product assemblers and the sales channels would be able to focus on one product type rather than three.

However, in much the same way as the mobile telephony market, the absence of agreement by standards bodies and manufacturers in the US and Europe has led to the fragmenting of the wireless LAN (WLAN) market. To further confuse the issue, the US 802.11a standard will be adapted in Europe to conform to that region’s regulations; that variant will be called 802.11h.

‘It is totally not acceptable to have multiple second-generation WLAN technologies on the market at the same time,’ says Lars Godell, an analyst with Forrester Research BV in Amsterdam. ‘It will confuse users and the cost base will be too high.’

In the US, the first products based on the Institute of Electrical and Electronics Engineers (IEEE) 802.11a standard are being sold already. More products are due out this quarter. The 802.11-based WLAN standards are promoted by the Wireless Ethernet Compatibility Alliance (WECA) and are branded Wi-Fi (802.11b) and Wi-Fi5 (802.11a).

In Europe, companies united in the HiperLAN2 Global Forum, and the European Telecommunications Standardisation Institute (ETSI) are pushing the HiperLAN2 standard. Products are due out mid-2002 on the European market at the same time as products based on 802.11h are expected to appear in Europe.

‘HiperLAN2 is superior to 802.11h because of better throughput, quality of service support, security and integration with other network types,’ says Martin Johnsson, chairman of the HiperLAN2 Global Forum. However, HiperLAN2 products will be about five per cent to 15 percent more expensive than 802.11h products, adds Johnsson.

The two 5GHz 802.11 standards are nearly identical, except that 802.11h adds TPC (Transmit Power Control) which limits the PC card from emitting more radio signal than is needed, and DFS (Dynamic Frequency Selection), which lets the device listen to what is happening in the airspace before picking a channel. TPC and DFS are European requirements.

Buyers have been looking for Wi-Fi logos on hardware boxes to assure compatibility. Wi-Fi5 is 802.11a, not 802.11h. But, adding to the confusion, 802.11h is likely to replace 802.11a and become Wi-Fi5, says Dennis Eaton, chairman of WECA, which manages the Wi-Fi brand.

‘Wi-Fi5 is straight 802.11a right now because that is what is available. I very much expect 802.11h to become Wi-Fi5,’ says Eaton, adding that TPC and DFS are handy features that also save power – particularly handy for mobile WLAN users.

‘802.11h is a good thing, even though it is only required in Europe. Chipmakers will implement it and it will become the worldwide standard,’ suggests Eaton.

802.11h is backward-compatible with 802.11a, but it is likely that 802.11a products bought in the US will not work with European 802.11h access points.

‘In Europe, access points could be set up to not accept connections from 802.11a devices. That could be a regulatory requirement,’ adds Eaton.

The HiperLAN2 and 802.11 standards have nearly identical physical layers, but are very different at the MAC (Media Access Control) level. The products are not interoperable.

‘Both standards are similar in the way they transmit radio, but are completely different in the way the data packets are formed and do things like device addressing,’ explains Andy Rolfe, principal analyst with Dataquest, a unit of Gartner.

802.11 is true wireless Ethernet, while HiperLAN2 on a technical level is more like wireless ATM (Asynchronous Transfer Mode), says Rolfe. Products based on the two standards can operate in the same room without causing interference, according to certain experts.

HiperLAN2 and 802.11h will face off in the European market, as HiperLAN2 products are not expected to appear on the US market anytime soon. HiperLAN2 support comes mainly from European telecommunications equipment vendors. L.M. Ericsson Telephone and Nokia are among the founding members of the HiperLAN2 Global Forum. HiperLAN2 is touted for its ability to guarantee specific bandwidth to specific users, says ETSI. There are quality of service standards being developed for 802.11, adds WECA.

Due to a number of factors, 802.11h and the Wi-Fi brand in particular seem to have caught the attention of the analysts.

‘Wi-Fi has the advantage that it is already known and that people are already using 802.11b,’ says Evelien Wiggers, research analyst for European Enterprise Networks with International Data (IDC).

‘802.11 will win in the end because users are familiar with Ethernet, both at the technical and the brand level,’ says Dataquest’s Rolfe.

This view is reinforced by Forrester’s Godell, adding that the 802.11h and HiperLAN2 camps are ‘digging a grave for themselves if they do not agree on a single standard.’

‘It will be mutual disaster for them, but good news for those people selling first generation WLAN equipment. For a lot of users the bandwidth they get from first generation WLAN is good enough,’ continues Godell.

According to Sebastiaan de Haas, WLAN specialist at Acal Nederland BV, one standard sure would make life simpler, but it really only matters for users in public places, such as airports and hotels. Acal Nederland uses a Cisco Systems 802.11b WLAN network in its Eindhoven office, The Netherlands.

‘You pick the standard you like best for your office building and it will work. A problem arises when you travel, want to use a public WLAN hotspot, and it turns out your card supports the wrong standard,’ says De Haas. ‘Sure, if you keep it simple products would be cheaper, and that is always nice.’

Representatives of the HiperLAN2 Global Forum and WECA agree that a single standard would be better, but in the short term it will be up to the market to decide which standard will be successful. In the longer term there are hopes for collaboration on a single standard.

It could take five to 10 years for a standard to prevail, unless the primary users of the 5GHz band, the US Department of Defense and the North Atlantic Treaty Organisation (NATO) push for a single standard, according to Johnsson of the HiperLAN2 group.

‘There are serious concerns from the US Department of Defense and NATO who use the 5GHz spectrum for satellite and radar systems. These kind of pressures might lead us to unite our efforts and speak with one voice and come with one standard,’ adds Johnsson.

Meanwhile vendors are preparing to come out with access points that have several slots to support multiple standards and PC cards that also support a host of standards. All this adds to the cost of the product, highlight analysts and vendors.

Despite the confusion, the answer for users is simple: stick with 802.11b, some suggest.

‘If there is a delay in the introduction of a single standard – no problem! Users are not ready to replace their 802.11b hardware anyway,’ concludes Godell.

Read More: Hardware & Equipment