* Posts by John Robson

1568 posts • joined 19 May 2008

Tesla books over $8bn in overnight sales claims Elon Musk

John Robson
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Re: @ bazza

"The average automobile engine is only about 35% efficient, and must also be kept idling at stoplights, wasting an additional 17% of the energy, resulting in an overall efficiency of 18%.[7] Large stationary electric generating plants have fewer of these competing requirements as well as more efficient Rankine cycles, so they are significantly more efficient than vehicle engines, around 50% "

Grid losses:

"Total losses: 1,423.5 MW (2.29% of peak demand)"

Charging efficiency:

80-90% (theoretically 92%, but who gets that)

So even ignoring:

- Nuke plants

- Renewables

- Regenerative braking

You get 97%*80%*50% ~40% efficiency from an unrefined, centrally delivered fuel as opposed to ~20% for a highly refined and locally distributed fuel.

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Hi! Up here! I'm your Amazon drone. Do you mind if I land now?

John Robson
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Re: Prior Art

I wonder if "on a mobile device" covers applications on a drone?

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Amazon WorkSpaces two years on: Are we ready for cloud-hosted Windows desktops?

John Robson
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I presume...

that if you buy more than a couple of desktops the price comes down to something a little more reasonable.

1k/year is an awful lot for a system that could probably be set up in house for not much more than that (assuming that clients need to be added on in either case)

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Only 0.1% of you are doing web server security right

John Robson
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Re: Store the keys on the web server...

"On Dropbox? Really?"

I really didn't expect that the joke icon, or the </sarcsm> tag would be necessary. I overestimated the humour detection of commentards...

The point being that we can fairly easily defend a small piece of information against data loss.

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John Robson
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Store the keys on the web server...

and a copy on Dropbox, and you'll be fine....

Does this refer to losing the keys as in "I lost my house keys and now I can't get in", or "I lost my keys, and now Eve can impersonate me".

The first of those is pretty easy to defend against...

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Oh, sugar! Sysadmin accidently deletes production database while fixing a fault

John Robson
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Re: In a similar vein

"I once Ghosted a blank drive over a client's hard drive instead of the other way around - oops."

I have seen a RAID controller do that automatically...

Mirrored disks, one fails - alarm goes off, everyone carries on.

Pull it out, all good.

Pop in a new disk, all good

Array starts churning, excellent - copying data from one to the other, tea time.

Erm, where are all the files?

Why do we have two disks with identical unformatted data?

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Google publishes list of Certificate Authorities it doesn't trust

John Robson
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Re: Since users too often click through those warnings.

I'm sure you can turn it off - or just run your own CA - and install the root...

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John Robson
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Re: Since users too often click through those warnings.

"I would tend to agree, although in corporate environments the only root CA the clients need to trust is the in-house root"

Yes - although most companies don't MITM certain traffic (like banks etc) - they recognise that that would be seriously unethical.

Hence my "public" CA for these devices, which would be well known and only valid within an RFC1918 domain, and potentially not even across routers. The idea is a limited mechanism for those connections to be trusted - which will satisfy home users, and will allow corporate users to get a proper cert on there easily.

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John Robson
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Re: Since users too often click through those warnings.

Surely no need for it to do so though.

There is of course the question of what you are trying to do with said cert:

- Authenticate

- Encrypt

Why not have a "public" root CA which anyone can sign their "self signed" cert with - but that is only trusted on RFC1918 devices

After all - I suspect we're looking for data encryption, not authentication for these devices. You could even use the MAC address as part of the cert, and validate the connection against that as well (no routing allowed)

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It's nuts but 'shared' is still shorthand for 'worthless'

John Robson
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"True enough; but if your trading algorithm really works, you can get the same result in time by just leaving it running."

Not if it is time limited - and if you can leverage 1000 times more money that you have available, then you can jump start yourself very fast indeed...

You can then invert that into your own scheme, and get 90% returns (assuming that the Quantico service is actually providing things like the high speed links that you don't have access to)...

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John Robson
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You get 10% of the return on someone else's money.

Not just one "someone else" either - as many as think you are good at your job.

That could be a 10% return on much more money than you can risk personally...

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A Logic Named Joe: The 1946 sci-fi short that nailed modern tech

John Robson
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Re: *Remarkably* sharp prediction?

"Back to the story, it seems to show a setup where each house has a local server and storage more than computers connected to the Internet and uploading everything to four giant US companies."

From the story itself:

"The tank is a big buildin' full of all the facts in creation an' all the recorded telecasts that ever was made—an' it's hooked in with all the other tanks all over the country—an' everything you wanna know or see or hear, you punch for it an' you get it"

That sounds like a few interconnected data centres to me...

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'Hot Tech Talent' IT job board ads caught up in sexism allegations

John Robson
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Re: Image this

"I haven't seen any ads showing blokes. I saw th ad with a woman and just sighed. If you want to appeal to women to join the tech industry, why do you think this would attract them to the profession? Again, why would showing a sizzling hot stud attract men to the industry? Now, if you should men and women with their pockets loaded with dosh, looking happy and successful, that might work."

Maybe the women are there to attract the men and viceversa?

Maybe not everyone is motivated purely by money?

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Who'd be mad enough to start a 'large-scale fire' in a spaceship?

John Robson
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Re: So, the next time you see a falling star ..

It's generally shock heating - i.e. heating due to compression.

Meteors are generally fast enough that the air just can't move out of the way

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John Robson
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Why wait to downlink?

Is it just me or would others not activate this and want as much data as possible to be instant telemetry, rather than waiting until it's over before downloading it all?

If it goes "unexpectedly" then you at least get some data...

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'Just give me any old date and I'll make it work' ... said the VB script to the coder

John Robson
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I assumed everyone here had heard of...

The Daily WTF

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Brits shun nightclubs and CD-ROMs for lemons, coffee and woman’s leggings

John Robson
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Only if it's not plugged in...

WORM media has many benefits, and backups are one seriously good case for them

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Dropbox slips 500PB into its Magic Pocket, not spread over AWS

John Robson
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Now they do, rather than Amazon being the only ones...

I still don't...

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Nest: It's no longer all about you. Now it can recognize your kids, too

John Robson
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Re: Not under my roof you won't

"@John, I'd agree that your own, custom designed system will be a harder nut to crack, but the key issue here is that we're talking about volume produced products which are given to people who don't understand the very basics of security, usually because they're Joe Average - it's only us with our warped and twisted minds that immediately spot the inherent problems :)."

Yes - the custom nature makes it much easier - but actually the internal security doesn't need to be that complex. It's the remote access that's harder.

You could have matching internal security all of these things - and actually you could have fairly matching *external* security...

The value of the attack on each of these is still far lower than the cloud solution.

Obvioulsy having strong internal seciurity makes life better still, but reducing the value of each target makes a significant difference.

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John Robson
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Re: Not under my roof you won't

There's no need for it to be cripplingly expensive - I have a rasPi which runs as a security camera (and associated IR light), and controls (visible) lighting and secure access to my garage (rather nice when it's wet and dark).

Functions which logically hang together, and can be easily run by a very low power and low cost system.

There is an scp based data uplink to a hosting account under my control, so that security footage isn't lost in the event of an intelligent thief...

The security hole needs someone to break my VPN, then break my SSH key into the Pi - I reckon by that point they can figure out which pins to toggle on their own...

The reward is fairly low - one garage with some tagged cycles...

OTOH a commercial cloud based system has a much higher reward - Look I can see when any of these 100k people are out and unlock their door. Easy.

I'd like to run some digitally controlled TRVs and have that all handled by another RasPi.... But that needs to wait for a little while...

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John Robson
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Re: Not under my roof you won't

@Dan 55

Actually having those things working together is quite nice - but it doesn't require any external connectivity.

Open the door at night and have the lights come on...

A delivery man rings the doorbell, and your phone rings so you can talk to them, despite being at the school gate/shop down the road...

The issue is external connectivity, not that things can work together...

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Sexism isn't getting better in Silicon Valley, it's getting worse

John Robson
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I think it rather depends on :

a) how often you ask

b) how you ask

c) the context in which you ask

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Home Ebola testing with a Tricorder? There's an app for that

John Robson
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Re: With an iPhone?

The prime advantage of an iPhone is that they are readily available - and self contained. No need to get an extra screen and keyboard as well...

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Boffins bust biometrics with inkjet printer

John Robson
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Re: Not Surprised

more importantly - it looks like the technology on those readers hasn't improved much...

What can you do to defend against a printed fingerprint? Look at vein structure and heat as well?

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Software dev 101: 'The best time to understand how your system works is when it is dying'

John Robson
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Re: Is it just me ..

I did specify lab testing..

We used to do this at a previous place of employment - we'd run simulations etc, then we'd test on the real world. But we'd do so in a non destructive manner (fairly easy, we were testing torrenting performance, so we contributed as much as we could to the swarm)

They replayed an old set of data into the system in a lab...

This is a *good* time for the failure to occur.

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John Robson
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Re: Is it just me ..

In (lab) testing I want them to fail - and this is what happened here.

They tested against a known large load - and it fell over. They tweaked it and now it doesn't

That's the point of this testing...

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BBC telly tax drops onto telly-free households. Cough up, iPlayer fans

John Robson
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Re: Taxation Without Representation

We all pay taxes for things we don't use.

Some people don't use the health service much, others don't trouble the education system.

Some don't ever use the jails, or the rubbish collections...

That's kind of the point of taxes...

The BBC tax is somewhat anomolous because it is a flat rate - it's a per household tax, unrelated to income or wealth (at least council tax is related to the value of your home, so some loose indication of wealth)

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John Robson
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Pay for catchup...

Is this going to do the old BBC thing and charge if we watch itvPlayer?

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Google robo-car backs into bendy-bus in California

John Robson
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Re: Pfft! Stupid meat bag!

a) lidar still needs to be able to see the sandbags - which it did, but only after trying to make two lanes out of two.

b) the car has been programmed to ease traffic flow - that does mean asserting priority at times, else the whole system shuts down...

So it understands priorities and common behaviour (in this case making the lane into two lanes on approach to a junction is apparantly common practise, mostly because the American't can't paint - or don't stop at red lights... ;) )

So it started the two lane manouvre, as would a human, then had to stop - and pulled back into a gap in the traffic. Note that the traffic was still in it's own lane - so it could reasonably determine that it had priority in this situation. The bus driver either assumed it was parking or didn't give a monkeys about priority - we'll probably never know which.

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John Robson
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Re: @John Robson -- Whose fault is this?

@Mark 85

Very much in it's infancy, yet already with more experience (although possibly less varied) than I will ever have.

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John Robson
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Re: @John Robson -- Whose fault is this?

@Mark 85

And the failures are where self driving cars can really come into their own. They can and should have redundant systems, so they can simply drive themselves to a local service centre and get a replacement fitted - or, if they are seriously compromised, just stay put.

As opposed to the small majority of cars driving around at the moment with failed lights - their drivers know they have failed lights, they just don't care.

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John Robson
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Re: One at-fault accident in > 10^6 miles

@Nigel 11

Yes - they're testing it in the wild...

OK - the wild isn't a particularly difficult place weather wise yet...

But the car would be far better than you at seeing around the corner - because it will slow down on approach...

It will be better than you at fog/rain because it will have more sensors, operating at different wavelengths, than you do.

It will be better than you at night, because it won't be tired.

It will be better at dealing with potholes, because it will "see" them all, and plot a course around them - or correct the steering faster than you could.

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John Robson
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Whose fault is this?

The Google car tried to create two lanes of traffic when only one was described by the road.

- This was because of the wierd turn right on red rule, it was probably indicating right.

It then got stuck behind a stationary obstructon - the lane wasn't as wide as it looked.

When traffic started flowing it then went to merge with the traffic as a gap appeared.

The bus driver, in the same lane, drove their bus into the GooCar.

I suggest that the bus driver may have thought the Lexus was parked/parking if the right indicator was still on - else they should not have been trying to pass a vehicle in the same lane. Ideally the Lexus would have been indicating left at this point of course.

There are cars parked along that road in the streetview linked by a previous commentard.

As for their safety record - they have driven far further than the average driver ever will - and each time any one of them encounters an 'interesting' situation they *all* learn from it...

That's far better than the current situation...

After all how many people get killed by drivers each year?

30 thousand a year in the USA, another 2k/year in the UK

That's not a particularly high bar to exceed - and the advantage is that the "drivers" will get better over time, they won't develop sloppy habits, get tired, read an SMS, be cross with the kids in the back. They don't have "blind spots", they don't have tempers, they don't start sneezing.

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SpaceX Falcon 9 set yet again to soar aloft

John Robson
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Re: Oops...

Almost certainly deployed at 602km, but still travelling "upwards".

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Microsoft releases Windows 10 preview for Raspberry Pi 3

John Robson
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Re: There's Windows 10, and there's Windows 10 IoT

"Last time I looked, the relationship between Win10 (on real PCs) and Win10 IoT (on embedded devices) was similar to that between Windows NT (on real PCs) and Windows CE (on embedded devices)."

Yes - I know that.

My point is that it might not be a bad thing to have another OS available.

Occasionally it's useful to be able to fire up a windows VM - for whatever purpose.

I'd not mind having a Win10 minimal (or whatever they call the low end Win10 desktop) on a spare SD card. Win10IoT seems utterly pointless anyway, RasPi or no RasPi...

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John Robson
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Re: No, thank you.

It might be - but actually I wouldn't mind being able to throw a Win10 SD card into a Pi3.

I'm sure there will be "windows only" things that my kids come home from school with, so having an easy "pop this SD card in, machine will connect to the dirty network, do windows stuff" would be useful.

Of course the work will get sent back as a scanned photo of the work on a wooden table, embedded in a libreoffice document...With a note saying that it really should be possible to do homework on any PC...

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Lonely bloke in chem suit fuels Mars orbiter

John Robson
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Re: Ignition...

It may well be out of print - only took me a few minutes to find the pdf last time..

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John Robson
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Ignition...

With so many rocket fuel stories should the editors be linking to the rather excellent book "Ignition", as recommended by a fellow commentard a few stories ago?

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Apple hasn't announced the new iPhone 5SE and pundits already hate it

John Robson
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Re: Shall I be an analyst for the day?

"That said, they have access to far better market research than I do, and their earnings appear to vindicate them."

They at least say that the choices they are making aren't disastrous. But we can't tell if they might be better still with a range of device formats.

I have a broken 4S - bought from fleabay - simply acting as an SMS/iMessage gateway because they couldn't be bothered to support SMS in the SIM equipped iPad (and I prefer to use the iPad for SMS than my phone)

I suppose that makes it a *good* decision on their part...

The 4S won't see upgrades, but since it does absolutely nothing other than act as an SMS relay (with a prepay SIM) I'm not fussed.

If they ever make an iPhone that I am vaguely interested in then they are likely to get another sale - but the current range don't cater to what I want in a phone - at all...

I can't imagine that I'm the only person who has similar requirements/desires - I'm happy to be niche/unusual/odd, but I doubt I'm unique... (I'm not rich enough to be eccentric).

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John Robson
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Shall I be an analyst for the day?

Then I can tell Apple what *I* want.

Since I use a tablet for things that need a larger screen I don't care about screen size or apps.

I care about battery life, making calls, and some SMS (iMessage relaying preferred).

The other requirement I have is that my contacts get synced onto the phone for use in aforementioned calls...

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Apple fires legal salvo at FBI for using All Writs law in iPhone brouhaha

John Robson
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Re: "the world will not end"

"Oh, and changing th iCloud password is a good idea. It prevents an accomplice deleting data."

Do you really think that Apple deletes data when you ask for it to longer be on your cloud storage?

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US boffins propose yet another low-low power Wi-Fi for Things

John Robson
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if it's just sensors...

Then do they need a receiver to poll?

I mean a transmit of data each ${interval} and then every ${big_interval} transmit to say "send me more crypto information in the next 1 second"

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Sick burn, brah: SpaceX test fires rockets for SES bird launch this week

John Robson
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Hence the decision to aim for the barge, not land.

It will be tight, but they'll have run the numbers...

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Software, not wetware, now the cause of lousy Volvo drivers

John Robson
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Re: No no no

Although in this case it's possibly the *following* driver rather than the volvo driver...

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No tit for tat, or should that be tat for tit ... Women selling stuff on eBay get lower bids

John Robson
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And who is this Alison person?

Where is Janet?

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FBI iPhone unlock order reaction: Trump, Rubio say no to Apple. EFF and Twitter say yes

John Robson
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Re: Apple has supported alphanumeric passwords for ages

"There is no useful intelligence on that phone, and they know it. It is security theater."

So - let's go full conspiracy nut here:

- They've cracked the phone, and know there is no useful intel...

- So they don't actually care how long this drags through court...

- But they think they have public support because of terrorists...

- So we'll crack the armour with this one, then use it as precedent next time we want something...

Shame Apple are a step ahead with the secure enclave - at least I really hope they are a step ahead with the SE. I imagine it might find that it can't be updated without the passphrase/code soon...

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Why Tim Cook is wrong: A privacy advocate's view

John Robson
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Re: Insecure by design

They don't need to sneak it in like this though - they can be quite open about it, and have it as part of a normal upgrade. They could, I'm sure make a mechanism for enforced upgrades to certain modules, but it should still wait for the the phone to be unlocked (maybe allow 5 "wait" prompts?)

I like the ideas from a previous thread:

- Firmware/Software should only be updatable on an unlocked phone

- Charging should only be possible when authenticated*, or powered down

- Secure boot time passphrase permitted (separate from the unlock screen)

*Authenticated - maybe allow for configuring certain networks/geofencing for convenient charging at home, but frankly unlocking the phone when you plug it in is hardly a major chore.

This then means that the phone can't be indefinitely kept "asleep" by a nefarious individual - and brings the boot passphrase into play.

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The Nano-NAS market is now a femto-flop being eaten by the cloud

John Robson
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Re: I'm still looking...

Yes - but £200-£300 for them?

Seriously?

The orinoco ones are at least ~£100, which still seems expensive to me..

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Apple must help Feds unlock San Bernardino killer's iPhone – judge

John Robson
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Re: In next weeks news...

Along with a requirement to unlock the phone to start it charging when it's powered on...

The clock is a ticking...

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