No Wi-Fi HereAnother week, another big event, another twitter stream full of complaints about Wi-Fi. Rightly or wrongly Wi-Fi is touted above food, toilets, queuing, decoration and just about everything else as being critical to an event. It’s been the same for several years now with seemingly little progress, how can that be the case?

The first response is typically to blame the technology and there are certainly plenty of cases where poor designs and implementations are part of the problem. Building an effective, reliable and performing wired and wireless network is complex but not impossible. These days the main issues tend to lie elsewhere.

The first issue is cost. Delivering a true high capacity, high density network requires significant investment with a large chunk of the cost down to the internet bandwidth required. The price of low quality consumer bandwidth like ADSL and FTTC may be at an all time low but high capacity business quality fibre circuits are still very expensive, especially for short term use. The usage patterns of the attendees have also changed over the last few years with current demand as much about upload as download which, coupled with richer content, all continue to drive demand for more bandwidth.

You can provide the best Wi-Fi on the planet but if it isn’t backed up by the appropriate internet bandwidth then users will have a poor experience. There is no magic here, if you want 10,000 users to have a good experience you need multiple high capacity business grade links, yet most organisers see the cost of this bandwidth as top of the list for cutting, well above other items which ironically users complain far less about. 

The second problem is particularly significant in the exhibition and conference areas – rogue Wi-Fi. The Achilles heal of Wi-Fi is its unlicensed nature, which on one hand has allowed Wi-Fi to become pervasive across the globe rapidly but on the other hand is slowly killing it. Wi-Fi currently operates at two relatively narrow frequency bands – 2.4GHz and 5GHz. These two bands are divided into a number of channels which are shared by all Wi-Fi (and some other) devices. The problem is there are not enough channels available, especially at 2.4GHz so in a high density environment managing the channels which are available is critical to success. That in itself is hard enough but now add in all the exhibitors who have brought in their own Wi-Fi access points, then all the Mi-Fi devices and to top it off all the Bluetooth noise (which also operates at 2.4GHz) and you end up with a large conference hall with thousands of devices all shouting at each other to the point no one can be heard because it is just a mass of interference.

The idea that all of these devices can share the wireless spectrum effectively is simply not true in a dense environment. To make matters worse it’s a vicious circle – the more often an attendee or exhibitor has a bad experience the more likely they are to bring their own device next time further adding to the problem. Even worse is that every new Mi-Fi device has a little more power and those with their own Wi-Fi think more power and more access points will make things better raising the interference and noise further.

Those who work in this area have known for some time that 2.4GHz as a client access frequency at an event was a lost cause and the only hope was to move people to 5GHz as laptops, tablets and smartphones increasingly supported it. The extra channel capacity at 5GHz, no Bluetooth interference and fewer 5GHz Mi-Fi devices made for ‘cleaner’ air, unfortunately that is rapidly changing and soon 5GHz will be as crowded as 2.4GHz.

There are only a couple of solutions to this problem, the first is long term and probably unlikely. Wi-Fi needs more spectrum and there are various discussions and proposals for increasing the spectrum available but it also needs to be managed – separating consumer type devices away from lightly licensed professional frequencies so that each has its own space. This will not happen quickly and would take many years to trickle down through devices but it could be the long term nirvana to truly offer a reliable Wi-Fi service.

The second solution is not really technical at all, it just requires event organisers to listen to and take seriously what event IT companies have been saying for years – the Wi-Fi spectrum at events must be managed. In the broadcast arena spectrum management has been taken seriously for years and it works very well. If we want event Wi-Fi to work then the same approach must be used. That means taking a hard line when an exhibitor wants to use their own device – it has to be pre-approved with specific parameters or rejected, and the agreement has to be enforced. No more rogue Wi-Fi it ruins experience for everyone.

This is easy to say, it requires trust that an official provider is going to deliver a good service and I appreciate it is hard to enforce requiring support from all levels but it can be done (we have examples) and the difference it makes is considerable and everyone gets a working service. It doesn’t fix everything but unless something is done across the industry to support this approach then paying money out for Wi-Fi is pointless and frustrates users more than if there was no Wi-Fi at all.

Achilles was an all-powerful god with one deadly weakness in spite of his overall strength. As a baby Achilles was dipped into the River Styx, which was supposed to offer powers of invulnerability, by Thetis. When Thetis dipped the young Achilles into the river he held him by his heel and thus that part was not washed and become his weak point. The rest, which includes a poison arrow and a good shot, is history

The story from ancient Greece reminds us that everything has a weak point and with wireless technology its interference. Without acknowledging or managing interference the most expensive, well designed event wireless network will become useless.

In a recent industry forum interference became a topic with generated lots of questions so we have put together a brief list of some key considerations to ensure the wireless network at your event doesn’t suffer.

1. Manage expectations and set formal guidelines

Delegates and exhibitors should be informed in advance that any personal equipment will be subject to certain guidelines to prevent interference with the in-house Wi-Fi. It is recommended users are requested to sign a simple pre-registration form containing the guidelines prior to the event. Have technical resource or partner on hand should any exhibitor wish to ask questions.

2. Use a technology partner to scan the airwaves

Once guidelines have been set, wireless scanners can be used by on-site technology experts to ensure the agreements are being followed and to locate equipment causing interference. It’s not just other Wi-Fi devices that can be a problem – DECT phones, Bluetooth, alarms, telemetry systems and even industrial microwaves can all be sources of interference.

3. Manage other suppliers

Any wireless networks used by other suppliers should be taken into account during the early stages of Wi-Fi negotiations; wireless networks may be of equipment used by AV companies for example, so it is worthwhile engaging to pre-determine any possible interference and pre-assign channels so systems can coexist.

4. Get skilled up

Ensuring that the team running the event have access to technical resources or an on-site technology partner are essential in enabling an organiser to address any interference affecting delegates during the event.

Everything has an Achilles Heel

5. Put in place a back-up plan

If local interference cannot be eliminated, there should be a back-up plan to minimise the impact i.e. the installation of some hard-wire cables which delegates and exhibitors can use. Whilst wireless offers freedom, many venues suggest that those requiring a ‘guaranteed’ service should consider a backup wired connection assuming the device supports this.

6. Make the necessary pre-event considerations

Check the venue before choosing it in order to identify any potential problems; a good question to ask in the first instance is whether the in-house network can be turned off if it is not required for the event reducing interference.

7. Know your frequencies

Interference can often occur as a result of too many technologies crowding the same frequency channel;. A way of counteracting this is to advise those requiring a larger wireless range to use a 5GHz network, which can offer more transmission channels than the overused 2.4GHz. More and more devices now support 5GHz including a number of the current range of smartphones.

8. Use the right equipment

Domestic Wi-Fi equipment and even lower cost so called business equipment does not have the more advanced antennas and management to deal with interference effectively. Higher end professional equipment can automatically work around interference and deliver a much stronger & higher quality connection even when interference is present.

There is one thing that can challenge even the best designed wireless networks; interference. That is, the transmission of competing networks attempting to broadcast at the same time on the same frequency. At the risk of turning this blog into to a science paper we’ll keep it light, but it is interesting to note that we have been in several meetings over the past few weeks where the delivery of Wi-Fi networks has been challenging due to the amount of interference.

As venues and events deploy wireless networks that become ever more critical to delegates, press, production and exhibitors, interference is the elephant in the room. Managing rogue access points, or those using their own solutions is imperative in reducing interference, and ensuring that those who are trying to use Wi-Fi networks in the same place can do so.

Understanding the limitations

Wi-Fi technology is designed to communicate over a number of common frequencies. This allows smartphones, laptops and other client devices to know how to communicate with access points and each other. Within this frequency there are a defined number of channels, similar to the number of lanes on a motorway. The more channels or lanes you have, the more simultaneous networks you can have in operation. 2.4G Hz Wi-Fi networks have significantly less channels than 5GHz networks.

Spectrum Crusaders

The spectrum crusaders ride to their next rogue access point

Setting expectations

Just like expectations on stand power (i.e. would exhibitors expect to bring their own petrol generator into an indoor venue?), there should be guidelines for use of wireless technology. Those who do not follow the rules should appreciate that their equipment may be turned off since their configuration could potentially impact those around them trying to access and fully utilise the ‘in house’ Wi-Fi. This can be as simple as a form which is completed as part of the contract which asks a few simple questions about which channel their wireless equipment will be broadcasting from.

Watching the air & taking action

Once the expectations have been set, wireless scanners can be used to ensure the agreements are being followed and that those who are causing interference are located. In areas where others are complaining about service, it will be quickly evident who isn’t playing fair. This was carried out during the Olympics and was commonly accepted by exhibitors because the expectations had been set.

One wire to rule them all

Many venues would also suggest that exhibitors who need a ‘guaranteed’ service should have a wired connection and that is absolutely correct. In addition to interference, some wireless chips are better than others and some devices just have bad days, so if the device supports a cable and it’s practical to do so, then this is highly advised. However, as more and more demonstrations rely on tablet computers (especially with the new Microsoft Surface launch), wireless will be considered critical to some stands.