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Comment Re:Speed up summary (Score 1) 81

I worked for a now defunct company called Netli that did something like this. Not caching exactly, but putting proxies on either end of the path which would optimize TCP behavior. The speedups could be quite significant especially where latencies were high (long fat pipes), because your browser normally spends a lot of time waiting for entire round trips to occur as each new connection is opened and ramped up to speed. You can also "prefetch" content because you can determine which images the client will be requesting by looking at the HTML response.

It may not make sense to you that more speed is possible through the same pipes, but if you know how TCP/HTTP works at the lowest levels you would see there are a lot of delays that can be removed by such techniques. Google actually launched an equivalent service at some point but then withdrew it.

Comment Re:Growing pot is better. (Score 3, Informative) 411

There are some bitcoin mining calculators that can give you an idea based on present mining difficulty and your electric rates. Eg: http://www.alloscomp.com/bitcoin/calculator.php
Go to http://www.mtgox.com/ to see the present USD exchange rate.

Right now mining is profitable since the value of bitcoins has recently gapped up from a buck to $7. But as more people mine, the algorithm must solve harder mining problems so in the longer term it is a self-regulating process. I have contemplated giving it a shot. To make a profit you have to build the machines as cheaply as possible and also live in an area with very cheap electricity.

As a side note, the whole affair is a big waste of resources, just like gold mining. However, it's this intrinsic cost to create the currency that makes it sound money - as opposed to fiat money, which can be made at no cost to the person authorized to print it.

Comment Re:equity versus salary (Score 1) 349

There is also a special scenario in the event of a buyout, where all options immediately vest.

Actually, what usually happens is that the options are compensated as cash *in lieu of* equity. I.e. the acquiring company will write you a check equal to the per-share exit valuation of the company minus your strike price. Unfortunately the IRS treats this as ordinary income for option holders so you pay the maximal tax rate. That is, unless the employee took a risk and exercised while the company was still private - which you can do if you have the means, as soon as your options start to vest. If you do that at least 1 year before the buyout then you get the much lower long-term capital gains rate.

If I were working for a startup I would try to get fully vested shares (a "grant" of common shares). Or options with perhaps shorter vesting period so you can buy them out of your own compensation.

As a contractor you probably have no visibility of how the company is capitalized. Ask to see the "cap table" but they probably won't share it with you. You at least need to know how many shares are outstanding, and the valuation at the last fund raising to be able to decide if the equity is a good investment or if you should just push for more cash and invest it elsewhere. Try to guess how much money the company will need to raise in the future so you can figure out how much your share is going to be diluted by then. My guess is if the company is already up and running and able to pay you market wages, you're probably past the window of opportunity to make big bucks on options.

Comment Re:ssh is the same (Score 1) 298

You too can make one at home, connect the transmit pins of the RJ-45 to HOT on 110VAC and the recieve pins to Common.

This actually would not work as described because of ethernet's transformer isolation which provides common-mode rejection. If you're going to make a proper etherkiller you need to tie the Tx+ and Rx+ together on one side of the AC, and Tx- and Rx- together on the other side. This will properly cook the transformers on the other end.

Comment Re:Tabloid trash (Score 1) 858

No they are not!!! The original Walking Liberty Half Dollar was minted by the US from 1916 to 1947. http://en.wikipedia.org/wiki/Walking_Liberty_Half_Dollar The ones I linked to are a similar design but have no face value, are minted by/for American Precious Metals Exchange, and they say "American Precious Metals Exchange" on them. That was the entire point of my comment - did you even look at the link?

Comment Re:Tabloid trash (Score 1) 858

That's absurd. Are you even aware of the concept of face value vs melt value? One would lose money hand over fist passing off real silver as lower-denominated fiat money. Each of his one dollar coins contained several US dollars worth of pure silver. The word "dollar" is used around the world for other currencies besides USD. His was just a different "dollar".

You may not be aware that there are many other silver coins minted in the US which also bear eagles, liberty, in God we trust, and such. Here's one that looks like a quarter but costs $20.60. Would you accuse them of trying to pass them off as US 25 cent pieces?


Comment Re:AC vs DC (Score 2) 468

With AC circuits that have non-zero reactance, you must choose a conductor that can carry Imax, but the power delivered to the load is only Vrms * Imax * cos(phi), phi being the phase angle between the voltage and current.

With respect to RMS vs peak, you are thinking of the *voltage* rating (what the insulation can withstand), NOT the current rating. Economically the insulation rating is not low hanging fruit for optimization - the copper conductor is by far the bulk of the cost and this can not be downsized for DC because it is the average thermal dissipation in the wire that determines its current carrying capacity. This is the same for a given DC vs AC operating voltage and load.

AC circuits suffer from the skin effect [wikipedia.org] where the power travels more on the surface of the conductor rather than equally throughout its cross-section. This requires a larger solid or stranded conductor than would be required for DC.

Stranded wire is used for electrical distribution not because of the skin effect, but because it's easier to bend, pull, and terminate (except for #12 or smaller because usually you prefer it to hold its shape). At 60Hz the skin depth is 8.5 mm - it just doesn't come into play at such a low frequency for building power distribution.

Comment Re:missing the point (Score 1) 128

As for setting up a DMZ... you mean people don't already have this?

I didn't say DMZ, I said a guest network. A DMZ is a subnet that is intended to expose your servers to _incoming_ connections from the internet.

I'm talking about a NATted subnet can only initiate outgoing connections. Basically another private lan that is partitioned from your sensitive machines.

And BTW there are plenty of ways to root a machine that don't involve compromising the router. Trojans being the most obvious example.

Comment missing the point (Score 1) 128

If you are worried that someone can change what's on your TV you are missing the point. The real concern is that by rooting your TV (which might have a linux shell for example) this can then be used as a vector to access anything on your home network that would otherwise be protected by NAT/FW. More sophisticated users would be well advised to set up a separate guest LAN that can only get straight out to the net.

Comment Re:Redundant troll is redundant (Score 1) 485

Apple has been trading for a very long time at about 15x trailing earnings ex cash. Do you think that is high for a growing company?

If you wanted to argue that, say, AMZN is overvalued that is an easier case to make. But seriously I can not think of a single profitable, growing, stable company that is as _stingily_ valued as apple.

Instead of hand-waving, why don't you actually tell us which smarter investments you have actually made that have fared better since before the dip. Keep in mind Apple was one of very few companies that grew through the whole recession (unlike most blue chips they recovered quickly and just kept going).

Comment Redundant troll is redundant (Score 2, Insightful) 485

Why does someone have to be a "chump" to pay more for it? If the company's earnings have grown 10x then the company ought to be worth about 10x. Those earnings... do you realize they belong to the shareholders even if they just accumulate in the company's bank account? Dividends are a "feel good" disbursement for companies that aren't supposed to grow. If you want to invest in dividend paying companies go for it. Or you could buy apple and any time your holding is worth more than your basis, just sell some. You'd have done quite nicely even with that conservative approach, and yet still enjoy the feel of 0% capital appreciation that you crave.

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