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Enraged Verizon FiOS Customer Seemingly Demonstrates Netflix Throttling

Agripa Re:Alternative explanation (393 comments)

It's tempting to imagine the internet as a giant blob of fungible bandwidth, but in reality it's just a big mess of cables some of which are higher capacity than others.

Wibbly Wobbly Timey Wimey ... Stuff.

Just wait until it becomes more economical to sell IPv4 addresses via tunneling.

2 days ago
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Enraged Verizon FiOS Customer Seemingly Demonstrates Netflix Throttling

Agripa Faster VPN Access (393 comments)

Back when I was in the process of switching providers, I bought a subscription to a VPN service so I could have a secure connection and routable IP through public internet access points. Later one of the things I noticed with my new AT&T U-Verse service was that *all* access was faster in either latency or throughput using the VPN to tunnel through U-Verse to half way across the US including things like DNS. Some things were a little bit faster and some things were an order of magnitude faster.

2 days ago
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How a Solar Storm Two Years Ago Nearly Caused a Catastrophe On Earth

Agripa Re:FUD filled.... (212 comments)

That particular storm still caused catastrophic failure of a 500kV 1200MVA transformer at the Salem nuclear power plant in New Jersey. They happened to have a suitable replacement available which was originally intended for another power plant so they were only offline for a few weeks.

3 days ago
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Google Offers a Million Bucks For a Better Inverter

Agripa Re:so... (260 comments)

Unfortunately, that's not true. The output is AC and the input-referred current will reflect it, i.e. will be quite high when the output reaches its highest (340V). Since the input source has an equivalent internal resistance of 10Ohm and would droop too much, some bulk capacitance is needed to provide these 120Hz current surges.

I should have been more specific but I agree.

There are other ways to reduce input ripple current besides capacitive decoupling. A PFC stage operating in continuous conduction mode would help and may be needed anyway because of the voltage drop across the 10 ohm source resistance. I wonder if such would take up less space than extra bulk input capacitance.

3 days ago
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Google Offers a Million Bucks For a Better Inverter

Agripa Re:so... (260 comments)

I think the largest problems are physical construction and heat distribution. I could certainly design and build such an inverter but the construction methods needed to achieve that form factor are outside of my prototyping capabilities. This is one of those designs where the power components need to be laid out first with an eye toward thermal management which is integrated as part of the case. Forced air cooling would help a lot but comes at a significant reduction in reliability and operating life so I would not consider it a viable option.

The input is DC so there is no need for low frequency input decoupling. Large value input and output ceramic capacitors are common in high density DC to DC converters although they can make frequency compensation tricky because of their low ESR. I doubt that would be a problem here.

4 days ago
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Google Offers a Million Bucks For a Better Inverter

Agripa Re:College kids created Google, Microsoft, Faceboo (260 comments)

I think the hard part in this case will be the physical design and construction to stay within the thermal constraints. Brick style power converters have power densities and efficiencies in this range but are designed to be attached to a metal surface for heat dissipation and Google's requirements do not allow for that.

Active forced air cooling would help a lot but also make long term reliability poor.

5 days ago
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Google Offers a Million Bucks For a Better Inverter

Agripa Re:so... (260 comments)

what is the state of the art w.r.t. the 12VDC->110VAC/60Hz 1kW inverters?

The ones which accept 48 volt DC inputs are better than 95% efficient but physically larger than Google's requirements.

5 days ago
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Firefox 31 Released

Agripa Re:no thanks (171 comments)

I am not sure if it is the same thing but I have been using the craptastic Classic Theme Restorer which also fixed some other UI problems.

5 days ago
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Nearly 25 Years Ago, IBM Helped Save Macintosh

Agripa Re:Blame Motorola (236 comments)

Motorola couldn't manufacture enough of the 68K CPUs, so Apple set up an alliance with IBM and Motorola (AIM). The first generation of the PowerPC was fast and easily manufactured.

I always wondered about this. At the time we had problems getting *anything* reliably produced out of Motorola and the standard procedure became to only design in parts which were available for shipping immediately and sometimes even that was not good enough. A majority of their products appeared to be on eternal allocation and unavailable. So I had a good chuckle about Motorola producing PowerPC chips for Apple and predicted that relying on Motorola would be a problem for them.

about two weeks ago
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Nearly 25 Years Ago, IBM Helped Save Macintosh

Agripa Re:Really miss the 68k (236 comments)

The later 68k processors had at least two serious problems; the address registers only supported a subset of the instruction set limiting their usefulness but even worse, the double indirect addressing mode really clobbered the high performance pipeline designs needed to compete with the Pentium and later which is when Motorola threw in the towel.

about two weeks ago
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Nearly 25 Years Ago, IBM Helped Save Macintosh

Agripa Re:Intel (236 comments)

That was not unusual as up until recently this occurred for all major processor transitions. Later processors were further pipelined to take advantage of newer processes and higher clock rates so the comparison between generations "at the same clock speed" is often misleading because the earlier processors would never be able to operate at significantly faster clock rates anyway. This is especially the case when access times of the register file and first level cache are taken into account.

about two weeks ago
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Verizon's Accidental Mea Culpa

Agripa Re:Connect with a VPN (390 comments)

I used to use my IPv6 tunnel to do this until AT&T blocked IPv6 (or at least protocol 41) unless they provide it themselves.

about two weeks ago
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Apple Refutes Report On iPhone Threat To China's National Security

Agripa Re:Of course not (134 comments)

Never would hosting or sending data to NSA's server.

about two weeks ago
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New Raspberry Pi Model B+

Agripa Re:So they update it, but... (202 comments)

If one grabs an RPi, sees the specs and tries to run a full blown desktop with heavyweight programs on it, it's going to suck. But that's not the fault of the RPi, that's the fault of the user.

How would it compare to a Pentium III at the same clock speed? They were commonly available with the same amount of RAM.

about two weeks ago
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UK Gov't Plans To Push "Emergency" Surveillance Laws

Agripa Re:UK is not a free country (147 comments)

I like the way John Ross put it:

A women is confronted by a big, strong, stranger. She does not know what he is planning, and she is cautious. Getting away from him is not possible. They are in a room and he is standing in front of the only way out, or she is in a wheelchair - whatever. Leaving the area is not an option.

So now he starts to do things she does not like. He asks her for money. She can try to talk him out of it, just like we argue for lower taxes, and maybe it will work. If it does not, and she gets outvoted, she will probably choose to give in to him instead of getting into a fight to the death over ten dollars. You would probably choose to pay your taxes rather then have police arrive to throw you in jail.

Maybe this big man demands some other things, other minor assaults on this woman's dignity. When should she claw at his eyes or shove her ballpoint pen in his throat? When he tries to force her to kiss him? Tries to force her to let him touch her? Tries to force her to have sex with him?

Those are questions that each woman has to answer for herself. There is one situation, though, where I tell the women to fight to the death. That is when the man pulls out a pair of handcuffs and says, "Come on, I promise I won't hurt you, this is just so you won't flail around and hurt either of us by accident. Come on, I just want to talk, get in the van and let me handcuff you to this eyebolt here, and I promise I won't touch you. I'm not asking you to put on a gag or anything, and since you can still scream for help, you know you'll be safe. Come on, I've got a full bar in here, and color TV, and air-conditioning, great stereo, come on, just put on the cuffs."

I tell women that if that ever happens, maybe the man is telling the truth, and maybe after talking to her for a while he will let her go and she will have had a good time drinking champagne and listening to music. But if she gets in the van and puts her wrists in the handcuffs, she has just given up her future ability to fight, and now it is too late.

How do you spot the precise point where a society is standing at the back of the van and the State has the handcuffs out?

about three weeks ago
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UK Computing Student Jailed After Failing To Hand Over Crypto Keys

Agripa Re:Seems appropriate (353 comments)

Even the copies that the police lost when they seized your equipment?

Funny, here are 9 disks/books/SD cards labeled "keys" from 1 to 10 and number 8 is missing which makes sense if it was out when the police executed their search and lost it.

about three weeks ago
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UK Computing Student Jailed After Failing To Hand Over Crypto Keys

Agripa Re:But it wasn't for "national security" (353 comments)

The same applies in the US. The Miranda waring "anything you say may be used against you in court" means literally that and anything you say when used in your defense is hearsay. Obviously this is not widely advertised.

Law enforcement memories are perfect when recalling what you said to use against you even when they lie which is just another reason to say nothing. The FBI has perfected this technique in connection with interrogations and local law enforcement learns from the best.

about three weeks ago
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Police Using Dogs To Sniff Out Computer Memory

Agripa Re:Any Memory?? what judge will go on just that? (415 comments)

A hit by a police dog IS probable cause.

So they trained the police dog to smell out child pornography on digital media. Nice.

about three weeks ago
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Germany's Glut of Electricity Causing Prices To Plummet

Agripa Re: don't be short-sighted (365 comments)

The same places that lack power generation capacity also lack baseline power generation capability. Exporting excess dynamic power to places *with* base load capacity will just make their base load capacity less economical.

about a month ago

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