Really? Creating discrete sand form negatives, then gluing those sand form negatives together, then filling the finished form with molten metal, letting it cool and harden, then removing the sand is a very niche market?
Pathway cannot just be any ol' pathway either, otherwise there are crosstalk problems.
Cisco's warranty on switches is very, very long. I've RMA exchanged switches that are ten years old. If they're willing to provide such a long warranty then it's not a big deal to replace a cooked switch from time to time.
Almost all WIFI that I've seen has been PoE, so that won't work well with a fiber solution.
Now for a microwave link or other special-purpose wireless point-to-point I agree with you, but I've found that for most campus-sized areas it's better to run fiber in the ground, and for metro-sized areas only the municipality can run point to point microwave as they're the only ones that control the elevations to have line of sight. Admittedly I live in suburbia, so there aren't tall buildings around here to make use of.
What are those shapes though, that can't be done subtractively without the expensive 5-axis machine, or can't be cast in some less expensive process? Think of the complexity of a cylinder head or engine block, where there are coolant passages, oil passages, mounting bosses, machined precision valleys, machined precision chambers, and often with modern automobiles, two distinct materials (steel/hardened seats for valves, steel or iron sleeves for aluminum engine blocks) and other difficult characteristics that are much easier to produce through casting and machining than they are through additive methods, and don't require five-axis machines to finish.
I just don't find enough uses for it to justify the floor or bench space for the machine. In subtractive manufacturing where one takes away material I can work in metal, plastic, and wood. I can cut, plane, sand, shave, drill, tap, or die-cut, and if I pick up one of those tabletop mills, I could mill and otherwise create channels, and these can all be done in three different materials.
Right now the only practical material I could work with on a 3d printer is plastic, and even then I'm limited to particular types of plastic. Plus, due to the texturing left by most 3d printers I'd have to plane, sand, shave, drill, tap, or die-cut anyway.
I can see design firms that need to rapid-prototype parts using 3d printers, before they ultimately design molds to cast the final plastic parts in. I can even see a few very specialized applications where the technology makes more sense, especially for one-offs, but otherwise 3d printing isn't mass-production.
Eight conductors, not six. Plus the interface supports grounding the housing and shielding the cable, so nine-ish. Typically 1U switches top-out at 48 conventional ports. 192 fuses is an awful lot of fuses.
We don't patch every drop either. Drops are installed speculatively and usually there are close to twice as many drops as there are devices mainly because the cost to run two cables is not significantly higher than the cost to run one cable, and the utility of having the extra cabling when it's needed is more important than the financial impact of the installation.
The number of ports should equal the number of devices, not the number of cables. As more organizations use wireless devices the number of ports needed has levelled-off, traditionally plugged-in equipment is increasingly wireless and those existing ports, if PoE, can be used for APs or for newer infrastructure like security door keypads, HVAC controllers and other SCADA equipment, or security cameras.
I like having about 20% free switch ports on a new installation, assuming that there are twice the number of cables as there are the number of ports. That usually means that last switch in the stack is a 48-port instead of a 24-port, or that a 24-port is added to the stack at the end if the last 48-port is nearly completely full, but it's nice to have a little room for growth without having to purchase equipment piecemeal and hope that the same model is still available, plus the per-switch cost is much lower when they're bought in larger batches so the cost savings of waiting is almost nonexistent.
I need a citation for that Nortel claim. PoE at the source is capped 36 watts, which is something like seven tenths of an amp spread across all four pairs.
How so? There are lightning arrestors that can allow PoE current levels to pass through. Old arrestors actually would block PoE, I know from experience retrofitting inter-building copper trunks...
Not all interfaces that are patched are necessarily live. Not all interfaces that are patched will let just any MAC address on to the network. Not all interfaces that will let one new MAC address on to the network will allow for MAC table flood attacks as they will cut-off the interface if too many MAC addresses attempt to use the interface too quickly.
There are means to reduce the problem if one wants to take the time to implement and maintain them, and if the organization will hire enough people to do the job.
Usually the best solution is to not patch-in horizontal cables that aren't in-service, and to use station cables that require a special tool to unplug from the wall and from the computer, but there are not very many facilities where this is practiced because it's incredibly labor-intensive to have to send a technician to move every computer and change all of the patching. Some organizations don't let the users move their own computers anyway, so for them it wouldn't be much more difficult to send the technician to the closet to make the change while they're at it, but I know that we don't have that kind of manpower.
Some fiber cabling has a metal wire in it so that it can be located in-ground. If that backbone cable is not properly grounded at the building entrance and that wire is touching or bonded to an improperly-grounded rack then weird things can happen.
Even more importantly there are lightning arrestors that are designed to provide a ground-path for lightning when it strikes an outside-mounted AP, camera, or manages to find an underground or aerial pathway between buildings outside of the building's cone of protection, and they even have models that can allow PoE to traverse the device. I'm not sure what happens with lower voltage and amperage though, where the threshold for the device failing-safe and shunting to ground is, nor am I sure of what happens to the cable itself if 120V or 240V with a theoretical maximum of around 20A for household outlets is applied. The Cat5/5e/6/6a cabling is rated to 600V, but 26AWG to 24AWG wire is not very large and cannot handle the same current as a 12AWG wire for the same amount of time. My assumption is that even with a lightning arrestor it'd probably melt the cable up to that arrestor before the electrical circuit breaker shuts off the service to the outlet being used to cause this.
There's a good reason why it's against code to install high voltage wiring and low voltage cabling in the same pathway.
I'm actually curious how much protection is built into the switch. Typically a certain number of ports are grouped to an ASIC, and the switches have to be able to handle a degree of dirty signal anyway, so it's possible that a single household high voltage spike might not hurt the switch or might only burn out a few ports as one ASIC cooks-off. I'm not exactly going to test this out though.
Re:Worse than the space station? No.
on
Let's Not Go To Mars
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· Score: 4, Insightful
I don't think anyone that's serious about going to Mars is assuming that resource extraction and management is a cakewalk. Many science fiction authors that tend toward Campbellian work like Kim Stanley Robinson have contemplated what a permanent Mars mission would look like, and before a human ever climbs into a rocket the nation-state has sent dozens of missions to begin the resource extraction process, mostly in the case of the science fiction authors, atmospheric extraction of vital elements, but the point still stands that a lot of mechanized work will happen autonomously to prepare the way for permanent human habitation.
Personally I think we should build an outpost on the Moon. It's a lot closer to Earth and it would actually be possible to build both lunar-escape vehicles and even to maintain a standby rocket ready to take a rescue mission to the Moon if an outpost had a horrible accident and still get there while people could be saved. The lack of atmosphere isn't the same as Mars, but the pressure on Mars is so low that it's probably good experience for long-term exposure of gaskets and seals to fine particulates without having significant air to help clean. It also has a practical side of being able to be used for Earth observations and even possibly as a telescope mount for space telescopes where humans could service them more easily than an orbital telescope.
There are lots of very difficult problems to solve, but we're pretty good at solving problems.
The M16 is powerful enough to kill. It's not powerful enough to kill in nearly all circumstances. If you're fighting an enemy that treats their battlefield-wounded soldiers like you treat yours- expending effort to rescue them and save their lives after they've been wounded, it works just as effectively as a more powerful round that has a greater chance of killing. If anything it's probably better, as the ammunition is smaller and lighter, the recoil is less, and the soldier can carry more rounds. When your enemy doesn't have effective aid stations, doesn't have field hospitals, doesn't have ambulances or helicopters, and can't really take care of their wounded and worse, might even seek glory in death while fighting, using a round that doesn't kill as quickly and might even leave a wounded man capable of fighting after being hit then it's an issue.
I have a movie poster of it hanging in my video room. I have it for the same reason that one of the senior execs at Cadillac has a picture of the Cimmaron hanging in his office, lest we forget...
All teenagers have the capacity to be attention-whores, and it's worse when they're in an artificial environment that forces a whole bunch of people to interact with each other that would not have chosen to be around each other. The class-clown mouthing-off to the teacher is an attention whore. The football player that wears his letter-jacket with pride is an attention whore. The goth with her white Manic Panic foundation and dark cherry lipstick is an attention whore. The geek, with his shit that he figured out how to work with and brings it is not really any different than the rest.
I wonder if Fiorina will use this in her bid for the Whitehouse... "I know the inner-workings of how badly government can run, in my time with HP I saw how Michigan wasted ten years in trying to implement a new computer system!"
Emissions, power, and fuel economy have a lot to do with each other. Running lean versus running rich versus getting the balance just right will affect different kinds of emissions and power output for a given amount of fuel burned, and different modes (acceleration, maintaining speed, coasting) are not operated the same way either.
What I suspect is that they were running these cars hella-rich on acceleration to give them the power that people wanted, and possibly running them lean while maintaining speed or coasting to attempt to regain the fuel economy lost during acceleration. That would give them poor emissions in two different ways.
Slashdot Mirror
Really? Creating discrete sand form negatives, then gluing those sand form negatives together, then filling the finished form with molten metal, letting it cool and harden, then removing the sand is a very niche market?
Pathway cannot just be any ol' pathway either, otherwise there are crosstalk problems.
Cisco's warranty on switches is very, very long. I've RMA exchanged switches that are ten years old. If they're willing to provide such a long warranty then it's not a big deal to replace a cooked switch from time to time.
Almost all WIFI that I've seen has been PoE, so that won't work well with a fiber solution.
Now for a microwave link or other special-purpose wireless point-to-point I agree with you, but I've found that for most campus-sized areas it's better to run fiber in the ground, and for metro-sized areas only the municipality can run point to point microwave as they're the only ones that control the elevations to have line of sight. Admittedly I live in suburbia, so there aren't tall buildings around here to make use of.
What are those shapes though, that can't be done subtractively without the expensive 5-axis machine, or can't be cast in some less expensive process? Think of the complexity of a cylinder head or engine block, where there are coolant passages, oil passages, mounting bosses, machined precision valleys, machined precision chambers, and often with modern automobiles, two distinct materials (steel/hardened seats for valves, steel or iron sleeves for aluminum engine blocks) and other difficult characteristics that are much easier to produce through casting and machining than they are through additive methods, and don't require five-axis machines to finish.
I just don't find enough uses for it to justify the floor or bench space for the machine. In subtractive manufacturing where one takes away material I can work in metal, plastic, and wood. I can cut, plane, sand, shave, drill, tap, or die-cut, and if I pick up one of those tabletop mills, I could mill and otherwise create channels, and these can all be done in three different materials.
Right now the only practical material I could work with on a 3d printer is plastic, and even then I'm limited to particular types of plastic. Plus, due to the texturing left by most 3d printers I'd have to plane, sand, shave, drill, tap, or die-cut anyway.
I can see design firms that need to rapid-prototype parts using 3d printers, before they ultimately design molds to cast the final plastic parts in. I can even see a few very specialized applications where the technology makes more sense, especially for one-offs, but otherwise 3d printing isn't mass-production.
Eight conductors, not six. Plus the interface supports grounding the housing and shielding the cable, so nine-ish. Typically 1U switches top-out at 48 conventional ports. 192 fuses is an awful lot of fuses.
We don't patch every drop either. Drops are installed speculatively and usually there are close to twice as many drops as there are devices mainly because the cost to run two cables is not significantly higher than the cost to run one cable, and the utility of having the extra cabling when it's needed is more important than the financial impact of the installation.
The number of ports should equal the number of devices, not the number of cables. As more organizations use wireless devices the number of ports needed has levelled-off, traditionally plugged-in equipment is increasingly wireless and those existing ports, if PoE, can be used for APs or for newer infrastructure like security door keypads, HVAC controllers and other SCADA equipment, or security cameras.
I like having about 20% free switch ports on a new installation, assuming that there are twice the number of cables as there are the number of ports. That usually means that last switch in the stack is a 48-port instead of a 24-port, or that a 24-port is added to the stack at the end if the last 48-port is nearly completely full, but it's nice to have a little room for growth without having to purchase equipment piecemeal and hope that the same model is still available, plus the per-switch cost is much lower when they're bought in larger batches so the cost savings of waiting is almost nonexistent.
And an analogy that doesn't actually explain the technical fault is useless.
I need a citation for that Nortel claim. PoE at the source is capped 36 watts, which is something like seven tenths of an amp spread across all four pairs.
How so? There are lightning arrestors that can allow PoE current levels to pass through. Old arrestors actually would block PoE, I know from experience retrofitting inter-building copper trunks...
Not all interfaces that are patched are necessarily live. Not all interfaces that are patched will let just any MAC address on to the network. Not all interfaces that will let one new MAC address on to the network will allow for MAC table flood attacks as they will cut-off the interface if too many MAC addresses attempt to use the interface too quickly. There are means to reduce the problem if one wants to take the time to implement and maintain them, and if the organization will hire enough people to do the job.
Usually the best solution is to not patch-in horizontal cables that aren't in-service, and to use station cables that require a special tool to unplug from the wall and from the computer, but there are not very many facilities where this is practiced because it's incredibly labor-intensive to have to send a technician to move every computer and change all of the patching. Some organizations don't let the users move their own computers anyway, so for them it wouldn't be much more difficult to send the technician to the closet to make the change while they're at it, but I know that we don't have that kind of manpower.
Some fiber cabling has a metal wire in it so that it can be located in-ground. If that backbone cable is not properly grounded at the building entrance and that wire is touching or bonded to an improperly-grounded rack then weird things can happen.
Even more importantly there are lightning arrestors that are designed to provide a ground-path for lightning when it strikes an outside-mounted AP, camera, or manages to find an underground or aerial pathway between buildings outside of the building's cone of protection, and they even have models that can allow PoE to traverse the device. I'm not sure what happens with lower voltage and amperage though, where the threshold for the device failing-safe and shunting to ground is, nor am I sure of what happens to the cable itself if 120V or 240V with a theoretical maximum of around 20A for household outlets is applied. The Cat5/5e/6/6a cabling is rated to 600V, but 26AWG to 24AWG wire is not very large and cannot handle the same current as a 12AWG wire for the same amount of time. My assumption is that even with a lightning arrestor it'd probably melt the cable up to that arrestor before the electrical circuit breaker shuts off the service to the outlet being used to cause this.
There's a good reason why it's against code to install high voltage wiring and low voltage cabling in the same pathway.
I'm actually curious how much protection is built into the switch. Typically a certain number of ports are grouped to an ASIC, and the switches have to be able to handle a degree of dirty signal anyway, so it's possible that a single household high voltage spike might not hurt the switch or might only burn out a few ports as one ASIC cooks-off. I'm not exactly going to test this out though.
I don't think anyone that's serious about going to Mars is assuming that resource extraction and management is a cakewalk. Many science fiction authors that tend toward Campbellian work like Kim Stanley Robinson have contemplated what a permanent Mars mission would look like, and before a human ever climbs into a rocket the nation-state has sent dozens of missions to begin the resource extraction process, mostly in the case of the science fiction authors, atmospheric extraction of vital elements, but the point still stands that a lot of mechanized work will happen autonomously to prepare the way for permanent human habitation.
Personally I think we should build an outpost on the Moon. It's a lot closer to Earth and it would actually be possible to build both lunar-escape vehicles and even to maintain a standby rocket ready to take a rescue mission to the Moon if an outpost had a horrible accident and still get there while people could be saved. The lack of atmosphere isn't the same as Mars, but the pressure on Mars is so low that it's probably good experience for long-term exposure of gaskets and seals to fine particulates without having significant air to help clean. It also has a practical side of being able to be used for Earth observations and even possibly as a telescope mount for space telescopes where humans could service them more easily than an orbital telescope.
There are lots of very difficult problems to solve, but we're pretty good at solving problems.
No, because we know that the amount of light reaching the solar panels well past Mars is insufficient to power a probe.
We're talking about Mars here, not about Pluto or any other celestial object.
Nah, they didn't care until the expected ink supply order never came.
The M16 is powerful enough to kill. It's not powerful enough to kill in nearly all circumstances. If you're fighting an enemy that treats their battlefield-wounded soldiers like you treat yours- expending effort to rescue them and save their lives after they've been wounded, it works just as effectively as a more powerful round that has a greater chance of killing. If anything it's probably better, as the ammunition is smaller and lighter, the recoil is less, and the soldier can carry more rounds. When your enemy doesn't have effective aid stations, doesn't have field hospitals, doesn't have ambulances or helicopters, and can't really take care of their wounded and worse, might even seek glory in death while fighting, using a round that doesn't kill as quickly and might even leave a wounded man capable of fighting after being hit then it's an issue.
Obviously you've never seen Robot Jox.
I have a movie poster of it hanging in my video room. I have it for the same reason that one of the senior execs at Cadillac has a picture of the Cimmaron hanging in his office, lest we forget...
War with no battles is Diplomacy. There are still casualties.
Salim Abu Aziz: Do you know what this is?
Harry: I know what this is...
[Salim smiles]
Harry: This is an espresso machine.
[Salim frowns]
Harry: No, no wait. It's a snow cone maker.
[Salim approaches Harry]
Harry: Is it a water heater?
All teenagers have the capacity to be attention-whores, and it's worse when they're in an artificial environment that forces a whole bunch of people to interact with each other that would not have chosen to be around each other. The class-clown mouthing-off to the teacher is an attention whore. The football player that wears his letter-jacket with pride is an attention whore. The goth with her white Manic Panic foundation and dark cherry lipstick is an attention whore. The geek, with his shit that he figured out how to work with and brings it is not really any different than the rest.
I wonder if Fiorina will use this in her bid for the Whitehouse... "I know the inner-workings of how badly government can run, in my time with HP I saw how Michigan wasted ten years in trying to implement a new computer system!"
I'm sure that the salesmen have long-since cashed any bonuses they received from landing the contract and moved on to other companies.
Emissions, power, and fuel economy have a lot to do with each other. Running lean versus running rich versus getting the balance just right will affect different kinds of emissions and power output for a given amount of fuel burned, and different modes (acceleration, maintaining speed, coasting) are not operated the same way either.
What I suspect is that they were running these cars hella-rich on acceleration to give them the power that people wanted, and possibly running them lean while maintaining speed or coasting to attempt to regain the fuel economy lost during acceleration. That would give them poor emissions in two different ways.