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Comment Re:A few items (Score 1) 338

I have not only seen cat3 in the wild, I still know of a dorm that is pre-cat3, uncategorized phone cable. It is a very loosely twisted air cable, and it is punched through standard 66 blocks, sharing cables with analog voice. Sometimes to get a room the 2 pair needed a single pair is stolen from 2 other rooms.

And for you cable monkeys out there, there are spots in that building with cables carrying ethernet on cables spliced with UYs

  Yep, it does work, and will even connect at 100M most of the time.

It is the last dorm on campus that isn't at least Cat5e, with several that are Cat6a now. It is becoming less of a problem, since almost all students are coming equipped with laptops, and 802.11n wireless is much more convenient. There are probably a few runs in that building still nailed down at 10half, because those runs were flaky enough that the NIC would negotiate to 100M and then error 99 percent of the packets.

Comment Re:A few items (Score 1) 338

I still have a box of single sided 3.5 floppies, on which the shutter latches open, and has to be manually released. Got the drive they fit also, it hooks to an HP portable via a current loop connection, along with a thinkjet printer. Haven't fired it up in a few years, but it predates all the flaky Chinese capacitors, so it should be good to go, barring decomposed drive belts and rollers.

Comment Re:Make it illegal (Score 1) 1199

The problem I see here is they say you aren't free to do whatever you want in your own home. For a municipality to not hire you or worse, fire you, for doing something legal on your own time in your own house seems to fly in the face of the spirit of equal opportunity law, even if it doesn't break the letter.

    I have no problem with a private company making whatever rules it wants, hire just women, or no women, or no blacks, or only people that own cats, whatever, but when a government does it that is contrary to my view of what liberty actually means.

    I notice in TFA that this is a policy enacted by commissioners, not a law which would have to be passed by a legislative body. I would imagine that it would be much more difficult to pass a law, and I have a feeling that it won't take too many years for policies like this to start falling in court. As the article mentions, the list of legal but potentially hazardous activities is fairly extensive.

Comment Wow, I have stuff like this (Score 1) 147

Somewhere in my collection of stuff I have a box of SGI knobs, and I think some buttons as well. SGI made them as serial devices to hook to their workstations, probably in the Indigo days, maybe as recently as Indigo 2.

I think these days you would look either to the music world or the arcade cabinet builders if you were looking for something that would give tactile input and didn't require a lot of hardware hacking.

Comment yup, they might (Score 1) 211

They might also be blue, or orange, or maybe frictionless black on black. Who actually thinks we have enough data to populate a computer model to make this wild conjecture? For Pete's sake, we can't even model Earth well enough to predict vague global temperature trends, how in the world can we have a valid model of an theoretical ecosystem that might or might not exist somewhere in the universe, which might or might not have life systems that use the energy from starlight to feed chemical reactions to store and use energy???? Can we please start using dewey decimal to categorize these stories so we know which ones are fiction without bothering to read TFA?

Comment Re:This is interesting (Score 1) 468

I guess I was referring to a transmission system, not a single long distance link. In a transmission system which includes the voltage reduction mechanism at the various tap-in points the fact that you can use simple transformers adds significant simplicity and reliability to the system, which actually matters as much if not more than the actual transmission losses in the wire. In fact, I understand that resistance losses in the wire are a good thing in climates that have icing problems in winter, since the HV lines are self heating. In fact, in the wikipedia article you mentioned it appears the only place HVDC has real transmission advantage over AC is in constrained wire cables, such as undersea links, where capacitance kills the AC. The phase decoupling when using a DC link between AC grids would also be extremely beneficial, but for other uses the inherent difficulties of switching and converting high power DC lines seem to outweigh the benefits

Comment This is interesting (Score 1) 468

It has taken a while for the economical advantage of this to trickle into user space. Electronic devices are almost all DC in nature, and the efficiency improvements here are not actually the computers, they are the lack of individual power supplies. Other poster have made comments about laptops, but normal laptops are actually no more efficient than desktops. They use less power, but that power brick is not any more efficient than a good desktop power supply.

What they get to do here is run one big, presumably very efficient power supply, and run it outside of populated space, moving the noise and heat generation to where it can be more efficiently controlled.

Of course telco types will say "Umm, yeah?" because a lot of telco heavy iron has been DC forever, for the same reasons TFA is bragging up this system.

This doesn't apply very well to consumerland, because houses don't lend themselves well to special DC wiring that doesn't easily move when you rearrange the room.

And before people start asking "Why don't the power companies just use DC?" Electricity transmission over distance is much more efficient as a high voltage/low current AC than DC current, especially since you can't use transformers on DC.

But I can very easily imagine datacenters utilizing a rack sized high efficiency DC power supply to run row(s) of server racks. This would tie in very nicely to Googles battery-in-every-server method.

Comment Re:this new file sharing app Ares?? (Score 3, Informative) 421

"Most college networks require a login to use- even from your personal computer(s)."

Actually, not a login, for the simple reason that that breaks all non-browser devices. They require registration of your device, but if they required a login then no Playstations, Xboxes, or iPhones would work, because you can't login with an email client or a video game. Once a machine is registered (Identified by the closest thing there is to unique, the MAC)then all the bad guy needs to do is check to make sure the target machine is not on at the moment, and spoof the MAC address. The traffic will be logged as belong to the poor innocent spoofee. And yeah, it may be less than 1% that know how to do it, but a single innocent person be persecuted or prosecuted is too many.

Comment Re:this new file sharing app Ares?? (Score 3, Informative) 421

Managed switches don't help prevent MAC address spoofing unless you actually allow a MAC to only connect through the port it first connected on, which kinda gets in the way of people roaming on wifi. Yes there are actually wireless solutions that will approximate physical location by access point triangulation, but good luck in a busy spot. Actually identifying a specific computer on an untrusted network (which they all are these days) is extremely difficult. Knowing what port a particular machine is plugged into is easy, but knowing what machine it is is not. Some wireless solutions now also backhaul all traffic to a wireless controller, so when you roam your connection point to the network doesn't change, but like I said, specifically locating a wireless machine is also next to impossible in a busy public spot.

The problem with MAC spoofing is the incredibly difficult time the person who gets spoofed will have proving their innocence. And of course the legal types on the plaintiffs side will attempt to tell a jury that a MAC address uniquely identifies a machine, and if the poor innocent spoofee gets a normal non tech-savvy lawyer they will probably succeed.

Comment this new file sharing app Ares?? (Score 3, Interesting) 421

Did I miss something? Have the people coding Ares implemented a new protocol, or is this college 5 years behind? Of course, having actually been involved in writing software to track computers on a college campus I am also curious how the college is fingerprinting machines to detect MAC address spoofing, but since this is a press release I wouldn't expect any technically informative information.

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