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Comment Re:Utterly misleading post. (Score 1) 99

The problem is that doesn't work.
This would work if you place the converter just in front of the retina. (but then it wouldn't work as the eye is not transparent to IR)
If you place it in front of the eye lens - contact lenses count - then you need the output visible light to be going in the same direction as the input IR light.
There are no common physical processes that can do this.
Hence, unfortunately, you need to actually have lenses and separate emitters.

In principle, this might change if you could have phase preserving detectors at 100nm resolution across the front of the 'contact lens' and phase preserving emitters at 100nm resolution across the back.

Naively, this will require significant computation and processing at 500000GHz *10000 megapixels.

So, not in the near term.
(I would be astounded if it happens in the next 50 years)

Comment Re:What about copy protection. (Score 3, Interesting) 92

By this exact same argument, many house-locks deployed are not 'security', and breaking them is therefore not a crime.

https://www.youtube.com/watch?... - I recommend.

A feature being ineffectual generally does not mean that it's not relevant, unless the law specifically says that the feature must be effective against skilled attackers.

Comment They're not base-stations. (Score 2) 35

http://www.aliexpress.com/item... is a typical example. (I have no relationship with this seller, they were the first hit for a large device on 'sms modem'.

They are basically little 'phone' modules hooked up to a power supply, antennas, and SIM connectors.
You simply insert 32 SIMs into the device, and you have 32 completely normal phones (from the networks point of view) that you can spam SMSs with.

They are not base-stations, they simply connect to the network as normal phones.

Base stations would induce other phones to connect to them, pretending to be the phone network.
The SMSs are in fact sent over the normal network, in the normal way.

Comment Re:What an open source baseband can be. (Score 1) 137

Basebands have not - with rare exceptions - been hacked.
They typically run signed firmware, with no documentation of the hardware platform, which considerably raises the bar.
Can they be hacked - certainly it's likely some can.
But, it's a very different matter legally between 'some nasty people cracked my phone' - and 'I made it freely accessible'.

The prospect of peer-peer file transport apps that have a side-effect of knocking emergency calls offline is real.

Radio is a shared resource.
A stronger or closer transmitter on a frequency will always interfere with a further one - there is little that can be done to avoid this - and what can be done has serious costs in terms of mobile phones.

Comment Re:What an open source baseband can be. (Score 1) 137

Calling them ASICs is both correct, and misleading.

The modem parts contain both processors running a fairly complex program (typically several meg), to do both the management of the high-level protocol, and the low-level data framing.
Then there are special units to write and read from the radio hardware at the precisely correct time and rate.
In addition, digital filters and low-level modulators and demodulators.

Doing a cell modem with pure SDR - with just analog to digital converters and then doing it all in software - will be extremely expensive, both in terms of power use and purchase cost.
The performance required of the general purpose processors goes way up.

Comment What an open source baseband can be. (Score 5, Interesting) 137

Open source basebands cannot, legally, in most parts of the world be up-datable by the user, which removes most of the interest.

There are several good reasons for this.
Radio is a shared resource. Cellphones only work as well as they do as the towers arrange it so that no cellphone is transmitting on top of another one.

The modem hardware is quite capable in most cases of transmitting right over the top of other transmissions. The worst case would be a free app turning up that gave free data transfer between nearby phones. And did this by ignoring the towers, and going direct.
This has the potential to knock off dozens of calls from the network per user, some of which may be emergency calls.

FCC/... approvals are inherently with a given software version of the modem - most of the behaviour of the modem is set by software - and changing that software without approval will void the approval of the phone.

In some countries, there is actual specific legislation.
If your open-source baseband could change the IMEI, then once you have been informed that this has been done, you are actually committing an offence if you continue to sell the phone which enables the user to do this in the UK.

Comment Some context from a hardware perspective. (Score 5, Informative) 147

Great - you don't want ACPI.

I'm looking at my Nokia n900 phone.
(merely because I happen to have a detailed understanding of the design).

Inside it, there are the following closed-source blobs running on turing complete processors.

LED controller firmware.
SIM java virtual machine
SIM raw firmware.
eMMC controller.
SD controller.
Hard-real-time modem controller.
Modem high-level engine.
Bluetooth CPU.
Wifi processor.
Main linux application processor
GPU.
I strongly suspect there is also an embedded processor in:
Power managment controller.
LCD.
Battery charge monitor.
GPS. (It's possible this is just an application running on the closed-source modem high level engine).

https://srlabs.de/rooting-sim-...
http://www.youtube.com/watch?v... (rooting SD cards)
http://www.youtube.com/watch?v... (battery firmware hacking)
Similar efforts have been done with reverse engineering the firmware of bluetooth devices, wifi.
The notion that you should only care about the code running on the CPU being open has always seemed really naive to me.

Comment Re:Which is why corporations are born criminals (Score 2) 247

Well - sort-of.
http://www.hmrc.gov.uk/avoidan...

There are problems with this sort of approach - implementing 'anti-abuse' rules means that now instead of (in principle) understandable legislation - you have a collection of people all of which may take a slightly different approach to decision-making.
The other issue is that it's not practically going to impact (for example) Amazon - or any of the other major tax avoiders - as they are able to use international financial structuring to avoid national tax, in a way that these rules do not impact.

Comment Re:For what jobs? (Score 1) 134

I would be interested in a real breakdown of 'make anything', and how that's measured.
It's a really hard thing to measure.
There are obvious things to measure - for example - total factory gate revenue.
You get very different numbers if you measure retail sales.

Similarly - a company imports 8 Chinese parts for $100, puts it in a $20 box, and sells for $400.

Getting the right numbers is hard.

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