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Comment In my experience Roundabouts work. (Score 1) 303

I have two experiences with roundabouts lately. Both of them happened in Massachusetts. The bad one happened at the the Route 2 roundabout in Concord MA. I remember waiting at least 15 minutes to get to the roundabout in Concord heading while heading westbound from Cambridge. I can't imagine that this traffic had a positive effect on the local air quality. The good experience was on Route 9 heading from Amherst/Hadley to Northampton. They have replaced a string of lights here with roundabouts and the effect was incredible. I traversed the new series of roundabouts at 4:00 PM on a weekday and traffic just flows at between 20mph and 40 mph. The Concord roundabout the older of the two. I wonder if it could be improved to give a better experience? In any case, I also believe that traffic through the route 2 roundable would have been much worse if it were a light.

Comment Re:Garek in HD? (Score 1) 118

Watching these shows now, Voyager's biggest mistake was making the marriage of the Maquis and Star Fleet crews far too easy to believe. After that gaff, for me Voyager's choice to be episodic rather than arc driven, is the second biggest problem. At the end of the day, there are high drama episodes of Voyager that are fun to watch but of the entire Voyager crew, the only member that I'm interested in seeing is Seven of Nine. I can't imaging a current Star Trek writer putting a cameo for Garrett Wang's Ensign Kim into Season 2 of ST: Picard. On the other hand, seeing someone from DS9 actually works for me.

Comment Re:Et tu, Suddenlink (Score 1) 243

It will be interesting to watch how Altice handles both Suddenlink and Optimum. This is doubly true if they handle them differently. I'm on Altice/Optimum. They are directly competing with Verizon FiOS for much of their territory out east. I pay $80 for 200/35. There is no cap. Heavy users get "traffic shaped". By that I mean that the week when I uploaded a 100GB photo archive up to a web service, speeds started at my upload of 35Mb/s but settled down to 10Mb/s after a couple of minutes. IIRC I could still add upload streams at that time and they would run at whatever bandwidth I had left. But big stream got limited to 10Mb/s after a few minutes of running full speed.

Someone on the Optimum Online Forum at dslreports should start lurking in the Suddenlink forums and vice versa.

Comment This article misses the point (Score 1) 217

I feel like this article was written by someone who hasn't been paying attention to the email landscape for the past twenty years. The checking services that the author lists don't make sure your DNS PTR records are correctly set up. They don't make sure that your server isn't an open relay. And they don't insure that your server is RFC compliant. They run your content through SpamAssassin and invert the score to rate your chances of successfully delivering a marketing message. I also run my own mail server. I'm not doing it to provide you with a medium for your marketing messages. I'm doing it to provide a noise free communications path for my users. I'm probably better than most because if my users complain about losing _any_ messages, I consider that my problem and use appropriate tools to fix it. But email has been under assault for the past twenty years by people who want to sell us things without regard for our interest in buying them. Anyone who expects that landscape to be a green pasture of ease rather than a battleground is sadly out of touch.

Comment Re:How much electricity do refineries use?? (Score 1) 188

I would bet that they use hardly any. Distillation of crude oil into component fuels like gasoline or diesel mainly requires controlled heat. In the best case a refinery would use natural gas or propane heaters to drive crude oil to the liquid-vapor transition temperature of whatever product they want and then use a tall column and a condenser and a condenser to capture their desired output. In the worst case the heater would be powered by the crude oil itself. It's quite likely that they just siphon off some of the diesel, which burns pretty clean, as a fuel for their heat source.

Comment Re:Exactly I've made this point here many times (Score 2) 188

That 93% efficiency is the ratio of watts arriving at the socket over watts generated at the plant. The watts "lost" between those two places are lost heating up the transmission lines. The 59 ~ 62% figure is the ratio of watts of electricity generated at the plant over BTUs of heat generated by burning fuel to heat water and create steam. Systematically, the 59 ~ 62% is more important.

Key to the discussion is the fact that energy comes in two forms: "heat" and "work". Heat is thermal energy. Work is the energy of motion or electricity. In layman's terms we usually don't differentiate between a "motor" and an "engine" but that difference is also very important here. Technically, a "motor" converts work into motion and an "engine" converts heat into work.

In the system that is an electric car powered by a remote power plant:
  • The heat comes from burning fuel at a power plant to create steam;
  • Passing the steam through an engine, a turbine causes the turbine to spin; this creates work;
  • The spinning turbine drives a generator converting work of motion to work of electricity;
  • The electricity travels over power lines to batteries in a car;
  • Later, we throttle the stored electricity from the battery through an electric motor to create motion.

Thus the overall fuel-to-motion efficiency of an electric motored car is: (59 ~ 62%) * 93% * battery_efficiency. Battery efficiency of Li-Ion batteries is well above 90% if I recall correctly. But assuming the worst, electric cars are at least 49% fuel-to-motion efficient.

In contrast, the fuel-to-motion efficiency of a car powered by an internal combustion engine hovers in the 35% range today due to market constraints on cars.

Note well that this analysis is generous to internal combustion engine automobiles because it does not account for the difference in energy cost for refining crude oil into typical automotive fuels like gasoline or diesel.

Comment Re:pfSense is a winner (Score 1) 238

Another vote for pfSense on Soekris here. I'll admit that I prefer straight up OpenBSD but for quick and dirty, pfSense is the way to go. Which Soekris is the real question. If you don't mind the spend, the Net6501 is best. It's got well supported gigabit nics so it will handle full speed traffic from Verizon FIOS, Google Fiber, or the top speed of a Docsis 3 modem. Net5501's show up on eBay irregularly in the $150.00 range. It doesn't make sense to buy them new as they are not much cheaper than the big brother Net6501. You can put a multi-port intel Gigabit card in a Net5501 but it will run hot so you probably want to spring for the larger rack mount case or just get the Net6501. Both the 6501 and the 5501 have more grunt than you need for a firewall/VPN box provided that you don't need to run 5 or more concurrent VPN connections terminating on the soekris' CPU. The last advantage of the net5501 is the presence of a USB 2.0 connection on the front panel. The net4801 is actually a workable solution for pfSense as a firewall/VPN termination box. They commonly show up on eBay in the $60 ~ $100 range. I wouldn't bid more than $80.00. If you find that the lack of CPU horsepower is getting in your way, search for a soekris VPN1411 card, again on eBay. These are typically very cheap, $25.00 and do hardware crypto offload, allowing a Net4801 to handle multiple VPN streams if that's your fancy.
Businesses

Supreme Court: AT&T Can Force Arbitration 415

suraj.sun writes with this unhappy news, as reported by Ars Technica: "The Supreme Court on Wednesday ruled that AT&T — and indeed, any company — could block class-action suits arising from disputes with customers and instead force those customers into binding arbitration. The ruling reverses previous lower-court decisions that classified stipulations in AT&T's service contract which barred class arbitration as 'unconscionable.' ... In cases where an unfair practice affects large numbers of customers, AT&T or other companies could quietly settle a few individual claims instead of being faced with larger class-action settlements which might include punitive awards designed to discourage future bad practices."

Comment Re:Audit necessary (Score 1) 136

Anyone using ssh to it's maximum security potential isn't sending a password across the channel more than once. On new systems I use some variation of the following to push my key onto the remote system.

$ ssh-add
$ ssh -A myUser@remoteSystem "ssh-add -L >> ~/.ssh/authorized_keys; chmod 644 ~/.ssh/authorized_keys"

Anyone using ssh with passwords would do well to read up on public key authentication in ssh.

-- Ecks
Microsoft

Submission + - BSOD on Deepwater Horizon

ctdownunder writes: "The emergency alarm on the Deepwater Horizon was not fully activated on the day the oil rig caught fire and exploded, triggering the massive spill in the Gulf of Mexico, a rig worker on Friday told a government panel investigating the accident...Problems existed from the beginning of drilling the well...[f]or months, the computer system had been locking up, producing what the crew deemed the blue screen of death." http://www.nytimes.com/2010/07/24/us/24hearings.html?hp

Comment Re:China asks Slashdot how to catch hungry minds (Score 1) 403

All network admins operate in the political domain. Several people here have mentioned that SSH forwarding works in China as I'm sure it does in Iran and Pakistan. Standard SSH on port 22 may just be too useful a tool socially and economically to block. As a consultant I find it rare to visit a shop that blocks SSH anymore even though most of the security admins that I know are well aware that with Putty you can forward any port inside to any port outside as you wish. Of the admins that I meet, most shrug this off as a non-problem saying:I know that users can circumvent any block on my firewall using SSH and port forwarding but the vast majority of my users don't have the arcane knowledge to do that.

We might not be the right people to ask since anyone on Slashdot could find Putty and the right configurations to do this in 15 minutes of searching on Google. And that assumes that the person asking is stuck on MS Windows. In Linux or OS X it's built into the OS.

I'd disagree that SSH is the best way to do this. A VPN is better because using a VPN allows you to hide in a class of users that the attacker wants to court and curry the favor of. The Chinese government wants our business so they must consent to our business people using strong encryption on our communications back home. SSH forwarding is one way to do this but a VPN is a much more common part of corporate IT security policy. If SSH is socio/economically difficult to block, a VPN is even more so.

Media

Low-Level Format For a USB Flash Drive? 252

Luyseyal writes "I unwittingly bought one of these terrible flash cards at Fry's and have managed to nuke two of them, successively. I have a USB flash card reader that will read/write the current one at USB 1.0 speed, but it locks up every Ubuntu and XP machine I've come across in high-speed access mode. I have read that if I low-level format it that it could be fixed, though my current one doesn't support it. My Google-fu must be weak because I cannot seem to find a USB flash reader that specifies that it will do low-level formatting." Can anyone offer advice for resurrecting such drives?

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