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5GHz Unlicensed WiFi Channels in the UK - White Paper

(Note: this white paper has been superseded with this new updated version ) I put together a few articles a few months ago talking about how the unlicensed 5GHz band is used for WiFi here in the UK. I thought it might be a good idea to consolidate all of the information that I found in to one place, so that people researching the topic could find and digest it more easily. Therefore I put together a white paper about how 5GHz is used for WiFi here in the UK. You can download it from here. There will no doubt be errors, omissions and other facts that folks would like to suggest. So, please feel free to drop me a note and I'll update this document from time to time to improve the quality of information that it contains. Nigel. Download the document from the following sources: Scribd Google Docs

802.11ad - Just for Home Cinema...Right?

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One of the things I love about Twitter is that once in a while you stumble across something that completely shifts your view of the world. I spotted this little nugget (posted by  @wifichef ) a couple of days ago, which made me significantly re-assess my view of the application of 802.11ad technology: " A deeper dive in to High Capacity WLANs:  http://t.co/L6kcx5oMI9 " Expecting another deep dive in to 802.11n high density WLANs (...small cell sizes, using 5GHz, band steering, disabling lower speeds etc.) I clicked through the link to see if I could find any new information. However, I was completely surprised to find myself looking at a  whitepaper  discussing the merits of 802.11ad! In fact, it actually highlighted the disadvantages of a traditional 'legacy' WiFi network - this had me hooked :) I must admit that I had dismissed 802.11ad (which uses the 60GHz band) as a niche technology that I'd probably hardly ever see in the Enterprise environments that

Cisco ACS Policy Decisions Based on SSID Name

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If you're using an authentication server (such as Cisco's ACS) to make policy decisions about wireless users, there may be times when you'd like to make a decision based on the name of the SSID that the user is joining. In this article, we'll look at how you can do this. In this article, I'm going to assuming that we are using a Cisco wireless LAN controller, together with a flavour of Cisco ACS 5.x. I've seen this method used with Cisco ACS 4.x (see references at the bottom of this article) and wouldn't be surprised if you could modify the technique for other RADIUS servers. When Googling about this subject, I don't see any results that show how to do this in ACS 5.x, so thought it was worth a quick note. Background In brief, when a wireless client is attempting to authenticate to an SSID on a Cisco WLC network, if 802.1x is being used to authenticate users, then various RADIUS attributes are sent to the RADIUS server (e.g. ACS) as part of

Aruba Tech Field Day - 802.11ac Product Announcement

Yesterday was the official launch of Aruba's journey in to the world of 802.11ac with their online (and real-world) Tech Field Day event where they presented their products and strategy for  11ac . I was a virtual participant, watching from over here in the UK. I have to say up-front that I do not currently supply or support Aruba products, but was very interested to hear more about their views on 802.11ac, together with their product offering. There was a lot of ground covered, but here a few (brief) notes of things that I found of particular interest for the sessions I managed to view. 802.11ac There was a very informative and lengthy discussion around 802.11ac technology, together with the lessons learned by Aruba in their testing to date. I won't cover all points here, but the headlines that stuck in my mind were: Smartphones/tablets will continue to be primarily single stream, capable of 80MHz bonded channel support Although 11ac brings significant speed a

Aerohive BR200-WP 3G/4G Backup Testing

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This is just a quick note about some interesting things I found out about the  Aerohive BR200-WP  today when I was having a look at our demo kit for a possible customer solution.  The  BR200-WP  is a great little branch router/switch/AP platform. It boasts a single AP radio (5GHz or 2.4GHz, 3x3:3!!!) and has 5 x 1Gbps switched Ethernet ports (one is the WAN uplink). If you throw-in in the fact that its cloud managed and has all of the usual powerful HiveOS features (VPN, firewall, AVC, airtime fairness...etc,. etc.), you've got a great branch-router platform. (Oh yes, I forgot to mention that it has 2 x POE ports too!) But in addition to the mass of great features outlined above, the BR200-WP has one more trick up its sleeve: 3G/4G backup. The unit has a USB 2.0 port which can be used to attach a 3G/4G dongle to provide WAN backup in the event that the main WAN link should fail. This was the area I was interested in taking a look at in my testing. You'll have t

Top 10 Things a WiFi Installer Does Not Want To Hear...

Here are the top 10 things (IMO) you don't want to hear from a customer when you arrive on site to install a new WiFi network (I compiled this rather quickly in a flippant moment - please don't take it too seriously...): Our networking guy, who was going to be helping you today, isn't available, I'm afraid he's... (choose from the following): On a late shift Off sick On leave Over-slept Double-booked Left the company Had a baby Buying a radiation suit Oh, you wanted POE ports for those APs? Our goods-in department has definitely received the kit, they're just not sure which part of the hospital it went to... Oh, we thought you were bringing the kit with you. No, we haven't received anything. You know that 500-person call-center where you said we might have issue with personal hot-spots? The good news is, we've introduced a policy of 'no personal hot-spots' in that area! As a sweetener, we gave all of the operatives a bluetooth

5GHz - 3 Missing Channels in Europe

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Last year, I put up a  posting  which highlighted the fact that here in the UK (and I suspect all of Europe) we often have 3 channels missing from our allocation of unlicensed channels in the 5GHz band.  Looking at many manufacturer data sheets, channels 120, 124 and 128 are often shown as not being supported. This is despite the fact that they are allocated for use by local regulatory bodies (OFCOM here in the UK). I recently posted a question about this on a partner forum of a major WiFi vendor that I deal with and finally got a definitive answer on this. In this post, I'll share my findings. The reason that these particular channels (120 - 128) receive special treatment is that they occupy frequencies that are used by weather radar systems. WiFi systems have to be very careful not to interfere with those systems during their normal operation. Therefore, WiFi equipment has some additional checks and tests imposed on it to make sure that it does not inadvertently cause any int