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Comment Re:First lesson (Score 3, Interesting) 84

I have two major beefs with IPV6. The first is that the end-point 2^48 switch address space wasn't well thought-through. Hey, wouldn't it be great if we didn't have to use NAT and give all of those IOT devices their own IPV6 address? Well... no actually, NAT does a pretty good job of obscuring the internal topology of the end-point network. Just having a statefull firewall and no NAT exposes the internal topology. Not such a good idea.

The second is that all the discovery protocols were left unencrypted and made complex enough to virtually guarantee a plethora of possible exploits. Some have been discovered and fixed, I guarantee there are many more in the wings. IPV4 security is a well known problem with well known solutions. IPV6 security is a different beast entirely.

Other problems including the excessively flexible protocol layering allowing for all sorts of encapsulation tricks (some of which have already been demonstrated), pasting on a 'mandatory' IPSEC without integration with a mandatory secure validation framework (making it worthless w/regards to generic applications being able to assert a packet-level secure connection), assumptions that the address space would be too big to scan (yah right... the hackers didn't get that memo my tcpdump tells me), not making use of MAC-layer features that would have improved local LAN security, if only a little. Also idiotically and arbitrarily blocking off a switch subspace, eating 48 bits for no good reason and trying to disallow routing within that space (which will soon have to be changed considering that number of people who want to have stateful *routers* to break up their sub-48-bit traffic and who have no desire whatsoever to treat those 48 bits as one big switched sub-space).

The list goes on. But now we are saddled with this pile, so we have to deal with it.


Comment Re: Still Catching Up (Score 1) 43

Verizon, Sprint, and U.S. Cellular still maintain sizable CDMA infrastructure. They cannot use Intel's gsm-only modem.

Where in my comment did I mention any of them, let alone suggesting they should get one or the other.

HINT: I've worked as a senior engineer for one of those companies...

Comment Flood defenses? (Score 5, Informative) 84

There is no flood defense possible for most businesses at the tail-end of the pipe. When an attacker pushes a terrabit/s at you and at all the routers in the path leading to you as well as other leafs that terminate at those routers, from 3 million different IP addresses from compromised IOT devices, your internet pipes are dead, no matter how much redundancy you have.

Only the biggest companies out there can handle these kinds of attacks. The backbone providers have some defenses, but it isn't as simple as just blocking a few IPs.


Comment Re:Terrible Power Cables (Score 2) 149

I find the worst point with all of them is near the end of the cable where it hits the connector.

If I think a given cable will get used regularly, I now just grab a pack of Sugru and add my own strain relief at that point. I find it helps a lot, but on one cable (and I forget which of the 28934774 cables I own it was...) it just moved the fray point from where it would naturally occur near the connector to the point where the Sugru tapered off.

I think the only other thing a person could do is both add their own silicone strain relief and maybe dunk the cable a few times in dip-it vinyl coating to armor the cable further.

It would be nice if someone would figure out that high-quality cables were desirable and make USB versions of welding cable with thick, high-flex EPDM jackets. I could definitely use a couple of Ethernet cables like this.

Comment Re:6.8 Billion (Score 1) 298

Yes. I've run numbers before. No, I'm not going to be bothered to do them again for a Slashdot chat on a thread that's rapidly becoming out of date. Feel free to do your own if you doubt me. Take a sampling of solar plants with a realistic capacity factor and a sampling of hydro plants with a realistic capacity factor, and compare. You'll need a broader sampling on hydro because solar thermal plants are "fairly" consistent (with the exception of compact linear fresnel plants, of which last I checked there was only one), while hydro reservoir sizes vary wildly for a given output.

Comment The issue isn't (just) speed - it's (also) range. (Score 1) 43

LTE is already pretty darn fast, so losing a little performance isn't going to make that big of a deal. It's not as if you can torrent to your hearts content without killing your cell phone bill.

The issue isn't just speed. It's also range.

At any given speed, the Qualcom can support it at substantially lower signal levels. 6ish dB in a lot of cases, a bit less in some, enormously more in others.

Look at the graphs in TFA. In addition to some specific pathologies that penalize the Intel chip farther, the bulk of the graph has the drop off looking similar but with the Qualcom shfited 5 or 6 dB to the right. (Those squares are 5 dB wide.)

6 dB is four times the effective signal strength, which corresponds to twice the range. That maps into four times the area served at that speed from a single cell tower (important in sparsely-served areas), deeper penetration into buildings and the like (in more heavily-covered areas). It can also map into more data pushed before a given area and channel allocation's bandwidth is saturated. 3 dB corresponds to twice the effective signal strength, 1.4ish times the radius, twice the area served.

If the modems were equivalent and the problem just the layout of the board and antenna, you'd expect the two curves to be the same shape but just offset. The shape is substantially different, so (board issues or not) something else is going on.

Comment Problem (Score 1) 153

He doesn't understand the limitations of technology. Unless quantum computing becomes mainstream, it's unlikely we'll have the processing power necessary to realize anything that we would recognize as AI (say, passing an unseeded Turing test with an arbitrary respondent).

It's been 35 years that I have been watching this and nothing better than an optimized Eliza has been demonstrated.

Comment Re:easily made up in peripherals. (Score 2) 371

if things ever get too hairy for a dell, your restore process is entirely automated in windows or linux. restoring a mac is nothing short of corporate witchcraft.

To backup: buy a Synology NAS. Enable the Time Machine service. Configure your Macs to back up to it. Voila, done.

To restore from scratch: hold down Command-R when booting a Mac. Tell it to restore from Time Machine. Wait an hour. Voila, done.

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