Wi-Fi for IoT – a boon or a bane?

Internet of things is hot now. But what technology should be used to interconnect those devices? Over the years there were multiple contenders, but Wi-Fi was always a bit aside, since it was always perceived as not too energy-efficient. Until recently…

Here’s a picture from a chip maker Rockchip, claiming (claiming!) that their Wi-Fi chip is the most efficient, overperforming even the specially designed ZigBee and BLE chips.

RockchipWiFi

While this seems as a reason to rejoice, promising greater speeds and technology convergence, I’d like to point one thing: 802.11b. Not n, not g, but b. Remember the protection modes, airtime fairness and other nightmares? They might come back in legions. And stay for what seems forever, as Rockchip claims “powering an IoT device for up to 35 years with a single AAA battery”.

What do you think? Is energy-efficient 802.11b chip a boon or a bane for modern WLANs?

P.S. News via SmallNetBuilder – excellent website, whose author is doing great job finding relevant news and testing devices. http://www.smallnetbuilder.com/wireless/wireless-news/32743-rockchip-unveils-iot-wi-fi-soc

Wi-Fi Riddles: Invisible 40MHz

A while ago I stayed in a small hotel that, had virtually all the problems of ‘small hotel wi-fi’ (including unresponsive one-device-per-room hotspot and lack of support outside of business hours. How many people stay at the hotel inside the business hours?). This is very typical of a WLAN installation made by a small local jack-of-all-trades shop. Unfortunately, I see this issue way too often, especially in SMB deployments. I hope this article will help some of the SMB integrators and their clients.

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Wi-Fi Riddles: ‘Too good’ signal is bad signal?

TooMuchPowerWhile I was working on the next part of the “Unobvious and overlooked Wi-Fi” (which is about channels), I got an interesting knowledge nugget from our engineering. We all know that there is a lower limit to receiver sensitivity, we all know that there must be some upper limit, after which the Rx signal is so powerful, it simply oversaturates the radio. But that is it? Now I know it, even though I did not ask for it explicitly – I merely happened to run into a situation where it matters.. Read on…

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Running a WLAN controller in VMWare Player

Motorola WiNG5.6 firmware images were finally posted last week, and along them, the VX9000 cloud controller DEMO image. I am very excited about it, as it allows me to run a VM version of Motorola’s top controller (or cluster, or hierarchy for that sake) right on my laptop! No need to say about potential for labs and demos this has.

In this blog I’ll review how I installed VX9000 image onto VMWare Player. Officially, VX9000 supports EXSi, Xen, Hyper-V or Amazon EC2, but for small setups something like VMWare Player or VirtualBox also works.

VX9000-GUIlogin

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[Opinion] 2×2:2 MIMO in Smartphones

So, Broadcom announced a 2×2:2 (867Mbps) chip for mobile devices, which of course generated lots of excitement.

Let’s see: 867Mbps Wi-Fi, you say?

  • Can you sustain such speed with your home Internet connection?
  • Have you seen hotspots offering such a high-speed Internet?
  • Do you have a RAID-enabled NAS at home for file transfers, since even the fastest SSDs do not allow for such read rates? [UPD] Well, clearly got carried away and confused MB and Mb here [/UPD]
  • And if the fastest SSD cannot read that fast, what makes one think their tiny phone will be able to write faster onto their embedded flash (or SD card)? The data I have is 35-65Mbps write rates on average.
  • Two antennas means 2x+ power usage of the WLAN module. Can you imagine effect on the battery life?

So, what is the point, then, you say? (more…)