Headworx

The "proper" Internet routing protocols are based on a concept of a "next hop" address. When a packet arrives at a router, it takes the destination address and based on the routing table determines the address of "the next hop" the packet should be sent to. And forwards it to this next hop router. This works reasonably well when the routes are not changing frequently. And when the next hop is available most of the time. What seems weird, some wireless architects try to apply this concept to low power wireless networks, where the routes do change frequently (wireless nodes have freedom to roam around) and availability of the next hop is not given. Wireless networks change topology not only due to the nodes physically moving, but also due to the noise floor of the channels fluctuating continuously. A node within 60dB (path loss) range is usually available (but this is just a couple of meters), but a node 90dB away may be falling down to be 110dB away jus...

I keep investigating the power drain experienced on my Blackberry Priv phone. And actually I'm getting some consistent results. The screenshots are taken at the end of days that were very similar from the phone usage perspective. And the one on the right has 50% more juice left. The first option that helps running longer is disabling 4G/ LTE in the Cellular networks menu. Clearly when switch to HSPA+/UMTS/GSM helps while still giving very decent mobile data performance. The second option, with results illustrated by the attached screenshots, is one I have almost entirely forgotten about. It is the Physical Web in Google Chrome. It is off by default so most people are not affected. I turned it on months ago and then simply forgot about its existence. It does very little but means a lot to the beacon industry, as it is meant to resolve signals from Bluetooth beacons into useful content links. It runs in a background continuously scanning for Bluetooth advertising packets. I am ...

Last week I posted on the airline industry racing for newly designed aircraft built of new composite materials to shave hundreds of tonnes of weight that do not have to be kept airborne. This is pure physics that dictates technology choices when designing a well performing airliner. Steel and aluminum are the two most popular materials used in ground and sea transportation today: cars, trucks, railroads, trains, ships. But you simply cannot use steel and even using aluminum becomes less of an option today when building an airliner. The same is true when trying to take technologies used in wired communication networks and apply them to wireless networks. This just does not work, because the physics of electromagnetic radiation in radio frequencies are fundamentally different from the physics of a copper wire or of a strand of glass. Fundamentally it starts with wireless being much more lossy, due to interference. Smartscrapers surround us. The density of wireless IoT radios toda...

Quite often I keep asking myself: "how do we really measure progress?". And in some remarkable cases the answer is very precise. Like in the aviation industry: in tons per year. Lufthansa has begun phasing out the A340-600 jets. Two weeks ago I saw a number of them sitting by a service hangar in Munich. And some have already made their farewell flights to Arizona . I remember - it must have been around 2002 when the 4-engine jet came into service. So exactly 15 years have passed and we now have the new queen of the sky - the A350. A350 is identical to A340-600: 300 passengers, 12000km range. With the one striking difference: it weighs 100 tonnes less. Which is incredible, considering this thing is design to float in the air. So if it is capable of carrying the same load for the same distance and has managed to shave 100 tonnes of ballast, imagine what it does to fuel efficiency. It is like not having to carry this weight across an ocean...! 100 tonnes in 15 years is a...