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Comment Re:Which one is more NSA-friendly? (Score 2) 131

From the article:

T-Mobile's HSPA+ 42 network hides a secret. While it delivers excellent sustained download speeds, those speeds don't look as fast in real life because of a very long time to negotiate the connection, which we measured as "time to first byte." This seemed to have to do with the network frequently switching between UMTS and HSPA+ modes when a connection was opened.

That explains the higher time to first byte compared to ATT HSPA. And then the latency on HSPA is higher than on LTE in general (plus on LTE the data connection is always on, not set-up on demand), as one key design goal of LTE was to allow a low latency (though there can be high variation depending on each operator core network, the radio part contribution is low with LTE).

Comment Re:France isn't representative of Europe (Score 2) 293

And one guy opinion may not be representative of the whole of France. I happen to work in a start-up in France, many of my colleagues are foreigners for all around the world (not counting EU people as they're free to work here so not a problem for them). Yes there is some paperwork to do, but if you have a competent HR or go through external competent HR consulting it can be done. It could be more fluid and smoother for sure, nothing is perfect. But it's not as dire as often painted on the web. It adds delay and cost, but if the company pays decent salaries it's not a big factor. You have to justify hiring a foreigner (as in the US), but again if the job is technical it is usually not a big issue. There is high unemployment on average but as in many places there is also shortage of qualified people in some areas, and the administration is aware of this. Of course if you want to get foreigners on the cheap at cut rate salaries it's a different story, but then I'd say the issue is not the country law it's the employer.

It's also possible to fire people, and it has been made easier recently. The company has to provide typically 3 months of advance notice. But it's perfectly possible to just pay this and ask the employee to leave immediately (what we typically do where I work: if there's a problem with someone there's no point lengthening the issue). It's typical to pay a bit more, like 6 months severance. Bigger companies often go higher for old employees, 1 year is not unheard of. But for a start-up I would assume it's on the low end. The issue on firing is not that it cannot be done, but that there is significant legal uncertainty around it: the employee can turn against the employer and challenge the decision or severance amount. Some changes have been done to bring clarity there, I haven't followed the details. It's a true concern, but in high tech which is a small world with usually reasonable people, this is quite rare. I've had contacts with ex-employees working and I expect that to be typical. Everyone benefit by making this as unpleasant as possible (and it's never pleasant). The situation is very different when a manufacturing plant is closed, it can becomes messy with factories being occupied and that's what people tend to hear about. But when talking start-up the context is different.

There are many things to improve in France and many legitimate criticisms on the legal and administrative situation. Still I feel that some paint a blacker picture to justify their own unrelated problems, or having left the country (which is ok in itself: go and explore. No need to pretend you just left hell thought).

Comment Rigor @ /.? (Score 1) 54

The fact is that I have more in common with you guys on /. than you might think. This is a community populated by engineers and technologists, not Luddites. You love great ideas. So do I. We may differ on the *economic value* of those great ideas, but I think this group debates innovation with the same passion and rigor that I do.

Now I'm concerned ;)
(emphasis mine)

Comment Re:Avoiding tracking has been patented (yes, reall (Score 1) 259

Not very useful. You don't need for the device to provide its location with GPS, the network can deduce it with no specific device support (except complying with the cellular standard for replying to the network pages and request for cells measurements). Google "RF pattern matching": it's 100% network side, and is more accurate than GPS in urban and semi-urban locations so cutting the GPS won't help at all here (and most people live in such environments nowadays). RF pattern matching is already deployed in some 2G/3G networks, and is currently being specified for future LTE evolutions.

In rural environments using the device GPS is still the most accurate method, but even then the network can provide a reasonable location estimation based on the device reporting the receive power of its serving and surrounding cells (a standard function, which is used to drive handover). And cellular networks do support this as not all devices have GPS.

Comment Re:Transmitter off won't work. (Score 1) 259

When in idle mode, a phone only transmit every few hours to indicate it's still "there". So transmission power is negligible and not a concern. It works as the GP explains (and it's the same principles for UMTS, LTE, WiMAX BTW). In idle, a phone will listen for a possible network paging that indicates an incoming call, SMS or data connection for a very short duration (a few milliseconds to a few tens, depending on the actual standard and implementation) every paging cycle. The maximum paging cycle is 2.56s for LTE and 5.12s for WiMAX and CDMA2000 for example. So it's regular, but only needs reception not transmission (and reception uses less power than transmission).

Then every few hours (3 or 4 is typical, that's standard dependent and configurable) the device will also transmit to indicate it's still in the expected paging area (the LA of GP for GSM). It's just a keep alive to detect a phone going off "uncleanly". In a clean power off, the phone is expected to sign-out to the network so that the network immediately redirects to the voice mail any incoming call. If an incoming call happens for an uncleanly shut down phone before it is detected as out by the network, the network will page it but after a while without the phone replying, it will also consider the phone out and redirect to voice mail. So it will be safe, but will take a bit more time.

Comment Re:Pro Exploitation CEO (Score 5, Informative) 1313

Breaking the law, like an awful lot of people in France, and nobody cares. There's this old notion of "cadre" / "non-cadre" in French labor law, and if you're an engineering or master level you're a cadre. Now if you're a cadre there's a special regime where hours are not counted, and the "35 hours" law just amounted to a lump of extra vacation days. You're still supposed to do 48h max but nobody tracks this. A lot of companies are using this and making 50+ hours is quite common. Yes, it is illegal strictly speaking but nobody cares. By "a lot" I mean a lot of big companies in internationally competitive markets, and most small companies. In high tech this set-up is mostly a given.

Now if you're in a big company, particularly if it's protected from international competition or has public roots, then it's a different story. You can be cadre and having to do 35 hours maximum, enforced with badging in some places with strong unions. One example I have in mind is doing military equipment and the French state is the main client.

And actually, even public companies themselves often break the law. Go to any public hospital and you'll find doctors and nurse pulling 60 to 70h work week just because there's not enough people to do the work and the hospitals can't afford to hire more. Everyone know the 35 hours are just not applicable in many contexts, and turn a blind eye to it.

The GGP story is maybe true but is just an anecdote in any case, you don't judge a whole country based on that. What you have to keep in mind is that 56% of the French economy is public economy, which is the highest in Europe. The public sector is then dominant, and rather protected, and can indulge in lazy practice (although there are hard workers too. They often get depressed after a while due to lack of recognition). But the others are working hard and efficiently enough to make France the n5 economy. And that's a statistically significant result not an anecdote ;).

Comment Interesting book on this same topic (Score 1) 626

Ok, I haven't read TFA (hey, this is /.) but I've read a book addressing this topic: "Sustainable Energy — without the hot air", available for free on the web at http://www.withouthotair.com/ but well worth buying IMHO.

Nothing too surprising: renewable energy alone won't be able to address our current energy consumption level, so must be go with a reduction of our footprint (better efficiency when possible, but also less consumption too). Big problems are storage, and the large investments required to move to renewable in a big way. "Investment" here means money obviously, but also energy and that may create an "energy trap" if we don't anticipate enough the switch.

The author is a physicists at root. He doesn't address the economics of such a transition (big topic, but not his cup of tea) but focus on the physics part. This may be seen as a big limitation, and in a way it is, but the positive side is that he focuses on more solid ground where reaching a consensus based on core physics principle is possible (among people of good will at least). He's very good at illustrating in a simple yet solid way the opportunities and challenge of renewable energy sources. He also puts some boundaries on possible efficiency gains for different domains (transport, heating...) and this too is well explained and very informative.

Highly recommended.

Comment Re:Devil's advocate (would want this system) (Score 1) 116

None of what you list requires two separate OSs, although of course having two separate OSs is a way to implement this. Having users and users data isolation is perfectly possible on a multi-users OS and been done in practice, although not in a mobile environment. The independent management support can also be done by trusted software on the single OS.

An hypervisor really becomes the required approach if one must have two different OSs on the same device. There the multi-users OS falls short. But I wonder how practical it is in this context: you want the user to have similar environments in both professional and personal mode.

The hypervisor approach makes sense when two very different environments must share a CPU. For example, a very limited secure environment (limited to be small and easier to verify) and a regular OS. To simply split professional and user environments it seems overkill.

Comment Re:Technical Question (Score 5, Informative) 151

The pricing is not so much driven by the technology than by what operators can charge. It's particularly true for text, where the margin is really really huge and unrelated to technology. But as it's a geek site let's go over the tech now ;) All 3 use slightly different mechanisms.

Short messages (SMS, or text) piggy back over the signaling protocol.

With GSM and WCDMA 3G (3GPP standards), voice and data share the same radio network. But on the network side there are separate core networks for voice (CS domain, for Circuit Switched) and data (PS domain, for Packet Switched). In the CDMA world there are actually separate radio networks for voice (CDMA 1x) and data (EVDO). This is why you can't do both voice and data at the same time on most CDMA phones: it would require 2 radios, which adds cost and complexity. Whereas with 2G/3G, both goes over the same radio network so both can operate concurrently with a single radio.

Starting with 4G, or LTE in practice, there is still a single radio network as before but now the core (EPC, Evolved Packet Core) is also unified and built over IP. Voice over LTE (VoLTE) is not common yet but it's basically VoIP built on IMS. All is unified, but voice is of course prioritized over best effort data using QoS both in the RAN (radio access network) and EPC.

Comment Re:Still going (Score 1) 488

So the PC and MSFT are NOT going away, but when AMD and Intel hit the thermal wall and decided to switch from the MHz war to the core war the chips they produced, hell even for the low end like the Athlon triples or the first gen Core based Pentiums on the laptops, are just sooooo damned powerful the users just aren't stressing them so they just ain't needing replaced nearly as often.

I predict we have less than 3 years before we see mobile, which TFA thinks is to blame (Protip: Its not) have the same damned thing happen to it that happened to X86.

Yes, and even less than that I'd bet. The latest ARM implementations, whether Cortex A15 or Krait, are already hitting a thermal wall. When benchmarking the latest Qualcomm quad-core S4 based on Krait on Nexus 4 and the cousin LG phone Anandtech saw some discrepancies in the benchmarks results that they eventually traced to thermal throttling. On one phone they had to run the benchmark is several goes due to software issues, and it had better results than on the phone where the benchmarks all run in one go. The only difference was due to cooling between tests on the first phone. To prove the point and avoid the effect they benchmarked both phones in a zip bag in a freezer :-P

Just as for PC chips we'll still see some incremental improvements with new processes and tweaks, but I expect this mobile next gen to be able to last for a while.

Comment Re:What are these low power servers good for? (Score 1) 116

I don't think so (but I'm not in this business either, so this is just my opinion).

These ARM servers are not for the general public. A lot of servers now go to the Facebook, Google and Amazons. These guys run their own stacks based on open source, so are not much tied to any ISA. Linux based software run fine on ARM. And they have a lot of loads that are I/O bounds (network mostly), so no need for huge CPU. And costs are critical, both in term of cost of hardware and power consumption (direct and cooling) as the services are often free. ARM is well know for its power efficiency, and the prices and margins are much lower than what Intel is used too.

These companies are the targets for ARM servers in a first step IMHO. Some already have expressed interest so it's not science fiction there: Facebook has join Linaro server workgroup recently for example. Once you have a foot there, you can scale later on to other markets. I don't expect ARM servers to go head to head with Intel in single thread performance for a long while, but I don't think they need to have good business either.

Comment Re:Just what Apple needs... (Score 4, Interesting) 116

It is not clear that they can beat future Intel CPUs on power usage, especially since Intel's manufacturing process leads the industry by a significant margin.

Everybody says that, but it's only true for the high performance / high power consumption process variant. It's not true for the lower power variant(s), which have some differences and are more tricky than the high perf ones (I'm not an expert on this but one issue for example is that LP needs larger wires to reduce resistance and power consumption. This requires in turn more precision to avoid shorts between wires. People who know more on this topic, please share. It's important to understand how the race can turn in the low power area). For low power Atom chips Intel is right now on 32 nm, while TSMC has been on 28 nm for a while now. It's a one year and half-node advantage for TSMC clients. And Samsung is also now on 32 nm (par). Intel announced they will speed up the availability of new finer processes for low power in the future, but based on their respective announcements Intel and TSMC would be on par for LP (we'll have to see how this turns out in practice...). This means that ARM clients can have a competitive process in the low power space today, and possibly tomorrow. It's likely that ARM clients would focus on many cores / low power servers for I/O bounds loads. They can be competitive there, and gain a foothold. Going to higher single thread performance can come later, it would be hard to attack Intel there in the short / medium term anyway. If you pick a fight, pick one you can win. And the ARM world has more experience in LP.

Comment Re:G729? (Score 1) 52

Yes, but where this matters Robust Header Compression (ROHC, RFC 3095. See also wikipedia) will be used so the IP header overhead is not a problem. And where it matters is over the radio link itself, where capacity is the most constrained. ROHC will reduce the IP/UDP/RTP headers to 1 byte typically. VoLTE (Voice over LTE) requires supporting ROHC in the LTE modem for example.

Comment Re:I don't get the car thing (Score 1) 377

It applies to convertible tablets, that can be used as a laptop with a keyboard (the cover type of the Surface, or any detachable keyboard really). It's not only for the Surface but could also be said for some Android tablet with detachable keyboards. I made a similar comparison, but with a seaplane not a futuristic car. It's not a good plane, it's not a good boat, but it has its uses. But it's not mainstream. So here's my very personal point of view.

I used to think that such hybrid devices would be perfect. Get a tablet and a laptop in the same device, so cool. I changed my mind. The reason is that it's either too small (for my taste) as a laptop, or too big as a tablet. And as a laptop the balance is all wrong: to have a stable laptop you want a light screen part and the weight on the bottom part, so it can easily rest on any surface and be stable. A convertible tablet has too much weight in the screen. So you need to put them on a table to be stable, which is less convenient. It's a tabletop not a laptop ;)

In the end I much prefer a true light laptop with a true light tablet (7" for me, I don't agree with Apple on that). Combined it's both lighter than my previous laptop, so no big deal. And they're better for their dedicated use-cases: the tablet as a simple "potato couch" / consuming device, the laptop for productive work. Plus I've no problem giving the small and cheap tablet to the kids, and I can to use the laptop in parallel. As for having separate devices, it's really no big deal. There are tons of ways to sync information across devices conveniently. And having different OS on both devices is a non issue too.

But really, to each his own here. It's more a matter of taste and priorities than anything. If you really need a single device for any reason, then why not a convertible tablet. Just like a seaplane, there will be use-cases where it's best. I don't know if my tastes are mainstream here or not on that topic, we'll see. But if the majority think like this I don't see much future for convertible tablets in the consumer space (actually, did many people bought the external keyboard for the Asus convertible for example? I'm not sure). Maybe for the professional space, for some applications (input while on the go, ...). But it's not the same volume at all.

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