Hotshots' hotchpotch hotspots: Office Wi-Fi is a great big botch Two thirds of IT directors admit their company's wireless network was rolled out without any kind of plan despite their businesses being dependent on it - resulting in inefficient and overloaded networks. The numbers come from Damovo UK and Ireland, who'd love to help companies plan their networks, obviously. But the study …
In a nice big office, with tech lot (not the IT folk) at one end our scanning of the 2.4GHz ISM band shows it fully occupied although the "office" networks are SSID supressed. We guess the access points are sited simply where they can a) find an unused 13A socket and b) where they can get a length of Cat5e. Our IT lot were supposed to have an open network for visitors, staff devices etc but it seems every time we find it and manage to get a connection they shut it down.
Yep no planning at all, and so much channel reuse even the Raspberry Pi's wireless connection keeps falling over.
Really big companies hire consultancies to create a radio map their sites, while small businesses just plug in a domestic-grade hotspot or two.
Bit of a sweeping statement, that.
We are a small business (@50 staff) but when we moved offices a couple of years ago, we spent as much time planning our WiFi provision in the new building (three floors) as we did our wired infrastructure. We did extensive testing using a variety of different access points and end user devices before deciding on a final configuration.
As a result we have a robust secure office WiFi network, and an accessible guest WiFi which is on a separate broadband connection.
Simple engage an expert! and expect to pay for an RF survey and network design tailored to your business needs.
With 11 AP's I can only assume that you're users are either very widely dispersed, or the building you are in has thick masonry walls between rooms (which is why an RF survey is always the best way to determine the number and location of AP's required).
When we moved in to this office I did plan the WiFi coverage to some extent - we still ended up with 6 access points for 12-18 staff!
Would be interested to know how their planning tools cope with 26" thick internal stone walls (the office is a 19th C rebuild of a priory that's then been extended twice).
I worked on the basis of full area coverage for 2 separate LANs (the corporate one and the external physically separated guest one that runs on ADSL). We get effective coverage everywhere and overloading shouldn't be a problem.
I know that Aerohive's planner will allow you to model this (other vendor's products may as well.) I know they they have sheet-rock, stucco, paneling, I-beams, concrete, but I don't know about 2ft+ stone walls.
I think you'd be better off with APs that have 4 radios and cabled antennas.
>planning tools cope with 26" thick internal stone walls
The tools/company I use work on the results from a full RF survey overlaid on to the building plans (Autocad drawings do make things a little quicker). Mind you the big problem I've had with tools is not so much the mapping of a single floor but their ability to handle multiple floors ie. the vertical dimension!
The question I would ask is whether you are using physically separate AP's for each network or a AP with multiple radio's.
...visiting Cardinal Hume School in Gateshead about 4 years back - they wanted (IIRC) 250 students all logged on via wireless in the main hall, with connections of above 2Mbit/s each. Cisco were given that one to sort out, and they managed it (from what the IT contractor and staff at the school were saying). There were other areas like this as well, such as the open atrium in the centre of the new building, but slightly lower density (APs dotted all around the perimeter though).
Having specced a dual a/b wireless system in another school, we used 45 APs for around 250 active users out of 1500 or so total - mostly because of the 100+year old heavy-weight construction and large site. That was a decade ago, though, and things have become much easier these days - I had a site plan with lots of circles on it to sort out the channel contention, and we walked the building with the contractor using an AP and wireless laptop to scope the project. Things might be a bit more organised these days, but surprises from doing it this way included finding the almost total block on signal from Pilkington K-Glass - we had 80% signal inside a room from an AP at the other end of the space, but zero a few inches away on the other side of the external glazing - another room without the newer glazing let the signal through as if it were open space...
>250 students all logged on via wireless in the main hall, with connections of above 2Mbit/s each. Cisco were given that one to sort out
I've found high density user populations to be Cisco's Achilles heel. For these deployments, I've gone with either Meru or Xirrus, with a preference for Meru due to their highly effective active management of the client-AP assignment.
Go Xirrus.
Once 2.4Ghz clients become less the norm you will be replacing AP's as Meru use fixed "chipset" radios in their access points. So..... 50% of your network will be redundant if you have a room full of 5Ghx I-Pads. Xirrus on the other hand can software define their radios in their arrays to 2.4 or 5GHZ giving better flexibility when new stations associate.
Also.... look at their new application control.......gives a really consistent experience.
Good to see you used a laptop for a survey.....nice touch......however.......big antenna, plenty of power and I bet you did the survey just on 2.4Ghz ?????? Be nice to know if you tried 5Ghz as well; or would the solution then be too expensive ?. What about tablets and smartphones, did you survey with them ? what was your set standard propagation figure for the solution in dB ? -65 ? what performance requirements did your customer demand ? Did you need to control applications ?
Unless all these issues are understood, your customer will be seeking a new supplier for wireless soon as each user could potentially have 2 or 3 devices and it will bring your proposal to its knees.
Coverage is just 20% of the requirement.
Moral to other bloggers - Hire a professional ! with references.
...2.4 and 5 Ghz - staff used the 'a' band, students and guests on 'b'. That job was in 2003, so we only bothered with laptop access, nothing much else hooked up back then ;-). It was my own network too, the contractor was hired in to sort out the wrinkles. Turned out to be dune-sized, but sorted out once the AP manufacturer realised their APs couldn't do 802.1x as promised. Airopeek traces used to convince them of that...
The Gateshead job was a day demonstration of the kit back about 4 years ago. Thanks for the recommendations - when my current place tackles site-wide WiFi I'll point my Network Manager in that direction. One of the benefits of being a bit of an old git is the promotions to senior management, but it does mean I have to give up being a fiddler and let younger and more up to date folks take over the day to day stuff.
We did exactly this during the early days of our wireless network. First, just a few apple base stations.... that became unmanageable, we moved on to Aruba Networks fully managed systems, with planning. This worked in 95% of the building Our beloved Tech Director left the organisation and the new guy brought in Netgear, and did a one to one swap, putting AP’s in the same place. We didn’t hear a peep from the users life was good! The contractor’s engineers were not happy with the locations of the AP’s, and submitted “a better” plan. Now we are back to crap in many parts of our buildings.
So to plan or not to plan?
Interesting to know on what basis the contractor's engineers 'better' plan was drawn up, particularly as I would trust the Aruba deployment plan.
Although I have seen AP's replaced but no consideration given to why the old AP's had external antenna's fitted...
If you go to practically any WiFi network installer they will provide you with a "WiFi network"; however, a wireless infrastructure enables so much more...
A business that approaches wireless networking from a mobile enterprise viewpoint will tend to invest in the up front consultancy that will deliver both a well planned infrastructure that enables the business to adopt new ways of working and the requirements that drive the detailed design of the WiFi infrastructure and it's integration into the existing ICT infrastructure.
Hence I suspect that many IT departments have rolled out 'WiFi' in response to user demands rather than pro-actively as part of a business driven strategy. Hence why the woeful lack of planning.
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