If there's a failure, then communication gets routed around it. Is service degrade? Possibly, since the path is usually much longer, but the degradation is held within limits.
There's a lot happening with packet based voice communications, and much of it is centerred around Quality of Service.
Those are the most common specs, but they can vary.
Originally the voltage was chosen so that you could pump enough current from the CO (Central Office), out the local loop, through the switch contacts on the phone (close when you lift the reciever), back the local loop, to activate a relay in the CO. This is how the CO knows you want to make a call.
If you had customers nearby (you were in the middle of Manhatten) you used 24 V. If you were in a rural area where customers were miles away you used 96 volts.
The ring voltage is a sine wave, with peak-to-peak voltage the same as your DC voltage. Superimposed over the DC then gives you a ring voltage that varies from 0 to twice the DC voltage.
Ring frequency varies. If there's anybody out there with party lines any more, one scheme used different frequencies for each user. The phones' ringers were mechanically tuned to the proper frequency.
Now, switches look for changes in impedance fro mline to ground to detect an off hook. Party lines are pretty much out of the picture, though subscriber carrier systems manage to perform a similar task. But somewhere out there I am sure there is some old equipment still in use. Phone companies don't throw anything away! You often see 60 year old equipment still in use in rural areas.
The phone network didn't fail... it was overwhelmed!
The phone network guarentees a quality of service, so there's a sharp cutoff to how many simultaneous users there are. If a trunk group is designed for n users then user 1 through user n will each get an 8kbps pipe but users >n get a fast busy. Conversely, if there are less than n users those users don't get better service.
The internet has no such guarentee, so as traffic increases it degrades. So if the path is designed for decent response for n users, the n+1 user still gets on but all users from 1 through n+1 get slightly degraded service. If there are less than n users then service is generally better than the standard.
It seems that they'd be better as an accessible source of raw materials. Metallic asteroids of iron & nickel, ready made stainless steel. Rocky asteroids provide soil, probably water & other organic materials. The comets would be an amazingly rich source of organics & water.
Accessible because you don't have to drag them out of a deep gravity well.
Launch from earth, with just enough materials & people to make it to an asteroid. Use that as a bootstrap, use the asteroid's material to make a basic habitat... perhaps sell the high value items (precious metals, or will water & fertilizer be more valuable soon?) to fund interim supplies, including workers, from earth.
Eventually get a minimg colony that can feed itself & also launch terraforming supplies to planets. Drop metals, water, organics for fertilizer toward Mars. Form a heavy metalic container, fill it with water, soil, fertilizer. Then cover it all in the slag left over from processing. The slag will burn off as the package drops through the atmosphere. Then you have the contents of the container as well as the metal container to recycle.
That hapenned on my '94 GMC. Not a software bug.
The truck has a plenum/hose that leads from the air filter to the intake manifold. Halfway there is a mass airflow sensor. At the intake manifold is a butterfly valve attached to the throttle via a linkage with a spring. The air can suck the butterfly valve open a bit more.
I had the same symptoms you described, it started after the car warmed up.
What I found was a tear in the hose between the sensor & the butterfly valve.
When cold, the engine computer runs open loop. It measures the air being injected (via the sensor) and injects the proper amount of gas for a good fuel-air mix. Step on the gas, open the butterfly valve, more air, more gas, more go.
With the tear, there was more air getting in to the engine. It wasn't flowing past the sensor so too little fuel was used, the mix was lean. Good enough to run, though.
It gets interesting when the engine heats up, then the engine computer goes closed loop. It measures the pollution in the tailpipe (more sensors). Too many hydrocarbons and it leans the mix, too much NOx and it injects more fuel.
So with the torn hose, once the engine warmed up the engine computer startd increasing the amount of fuel until I was idling at 35 MPH.
Some tape by the side of the road was a temporary fix. Some time puzzling through manuals at home, out of the rain, gave me the explanation.
On a recent trip to Japan, I noticed that most cabs had a GPS mapping system that shows congestion. It takes awhile to get used to your driver playing a "video game" while driving.
Also, almost everybody has new cell phones with GPS capability. So you're jammed in the cab with 3 Japanese and they've all got their mobile phones out with route maps & current position shown. Heading north through Yokohama there was severe congestion (no, just normal rush hour congestion, I was told). Now everybody is telling the driver what he should do.
The only thing anything worse than a carload of backseat drivers is a carload of backseat drivers with too much data.
I had watched the driver pan his display. It doesn't matter how much data you have, when everything is congested there is nothing you can do. We can't go forward, we can't go back, we should've stopped for a couple of sakes.
OK, after much discussion it was decided we'd use surface roads. These were congested too. The congestion data was only for major roads & highways. OK, so it didn't help. At least we aren't moving any slower than on the highway. The scenery is different, waterfront, docks, warehouses...
Wait! There is one person beating the traffic. Our cab was being passed! A woman on a bicycle -- steering with one hand while holding her mobile phone in front of her face with the other. Staring at her map.
My wife is an ex-cop. The training is to exhaust all possibilities before you shoot, but once the decision is made you aim for the center of mass an empty the weapon.
Anything else and you put yourself and innocent bystanders in danger.
I was in California a few months ago, on a business trip. The topic of discussion was a homeowner on trial for attempted murder. Somebody broke in and threathened the guy, said he was going to beat the crap out of him.
The homeowner had a gun -- legally owned it. He pointed it at the intruder and, when the guy still advanced & threatened him, the homeowner shot the guy.
The prosecuter said this was unecessary force. The intruder was unarmed and the homeowner shouldn't have used a gun.
I guess he was supposed to sit there and let the bad guy beat the crap out of him!?
It cost US! Re:Figures...
on
Gone Phishing?
·
· Score: 1
The costs aren't being born by the banks & credit card companies, they're being passed on to the customers -- US!
So even if you do everything right, you don't get caught by a phish, you'll still be paying. A portion of losses caused by others getting duped will be added to your fees and/or reduce value you recieve. The companies will pass the cost along to everybody & protect their bottom line.
This sounds like the HUD on some fighter aircraft -- some have mirrors but others use a high quality chunk of optical glass. It sounds like this approach takes a low tech chunk of plastic and corrects for the abberations in the electronics.
Cheap silicon wins again -- it's been supplanting copper, now optics.
A place I worked had a VP that, as far as we could tell, did nothing. Every project & department had to pay a part of his salary, though.
We finally found what his job was when government auditors showed up. He was the company scapegoat.
He got 9 months off work -- with pay. Within a month of coming back they announced he was retiring -- golden parachute, full pension.
This type of design was common with portable radios -- tube radios. I used to collect old radios & TVs and refurbish them when in high school. Portable battery operated radios, lunch box sized recievers for consumer use and trancievers for military or emergency services, had some amazing circuitry to reduce size & power.
An easy thing to do was combine several elements into a single tube. That meant a single power-hungry filament could support two triodes and/or pentodes, and possibly also a couple of diodes.
The circuit designs used were more interesting. A Motorola lunchbox-sized AM radio was made with 3 tubes. I remember one tube contained a pentode that was used as an RF amp, IF amp and first audio amp. They used a summing junction to sum all the input signals. At the output they used filters to seperate the three bands of frequencies.
There is some truth to what you say, but you don't need 100% market share world-wide to have a monopoly.
Monopoly has a lot of definitions, not all of which apply in all cases. Walmart often has a monopoly in a market area. They drive out the Mom & Pop businesses in small towns, removing any competition.
In the area I live, central NJ, there are enough people that they their tactics aren't completely effective. But small towns, isolated from larger metropolitan areas, are areas that they have certainly been able to gain a monopoly.
One of our customers setup an online site for vendors to bid on supplying them with telecommunications equipment. Vendors' equipment had previously been qualified froom a technical standpoint.
You could change options like price, delivery & support. The app had algorithms that scored your bid against the rest. The points for technical capabilty were determined from previous trials & fixed.
It was scheduled for 2 hours, with half hour extensions if there was a change by one of the top 3 in the last 5 minutes. The business would be split by the top 2 bidders -- we were trying for the #2 spot to maximize our revenue.
At the end (after half a day of this game!) we were surprised to find we were in the #1 spot. The company that we had expected to come out on top, that had been for most of 12 hours, didn't get any business. We found out later that the guy at the keyboard had had a heart attack and they dropped to #4.
A few years ago, where I used to work, I noticed a secretary using the copy machine on our floor. She was from legal & their machine was broken. She was making copies of a 4 inch stack of email printouts.
Her job was to print all of the emails her boss got, stamp them with a date, then make copies. One copy got filed, the other read by her lawyer boss. She'd then respond to emails per her boss's scribbles, file the annottated hardcopies, print the responses, time stamp & file them.
They never intended to run VoIP over the public network. In order to avoid these issues and to assure Quality of Service they'll run this service over a private IP network for the most part
The only part of the network that may not be VoIP might be the local loop. That is, they might combine your VoIP traffic with your internet trafic. But at the CO filter they'll out the RTP packets, sanitize them, and send them over their private network for the long haul.
The goal for them isn't to share voice & data (they've been doing that over the switched network for decades) but to reduce the cost of maintaining the network. An IP network is, to some extent, self healing & self routing.
Most of my work is via keyboard, PDA entries on a touchscreen, but for taking notes a fountain pen is still the best. A gentle grip, minimal pressure, light weight, I can take notes rapidly and for extended periods with without fatigue.
It can be oriented in any direction. The major concern is keeping it from arcing. The best way to keep it from arcing is to keep it well away from anything else.
Color tubes restrict how you can mount them. The guns are either arranged in an equilateral triangle (point up) or in a horizontal row with a pattern of red, blue & green phosphors to match.
Monochrome tubes give you a lot of options. Only one gun centered in the neck. No pattern of colored phosphors on the screen. It's all white so it's just spread inside the front of the tube. You can rotate the tube anyway you want, giving you infinite possibilities if it's round.
Old B&W TVs with round tubes made use of this. Most components were on a chassis at the bottom so it isn't top-heavy. Tuner & other controls somewhere near the top so it's easy to reach. Tube rotated to the side opposite the tuner so it's away from everything -- usually a bit above horizonal because the HV power supply will be at that end of the chassis & it's rather large.
Slashdot Mirror
There's a lot happening with packet based voice communications, and much of it is centerred around Quality of Service.
Originally the voltage was chosen so that you could pump enough current from the CO (Central Office), out the local loop, through the switch contacts on the phone (close when you lift the reciever), back the local loop, to activate a relay in the CO. This is how the CO knows you want to make a call. If you had customers nearby (you were in the middle of Manhatten) you used 24 V. If you were in a rural area where customers were miles away you used 96 volts.
The ring voltage is a sine wave, with peak-to-peak voltage the same as your DC voltage. Superimposed over the DC then gives you a ring voltage that varies from 0 to twice the DC voltage.
Ring frequency varies. If there's anybody out there with party lines any more, one scheme used different frequencies for each user. The phones' ringers were mechanically tuned to the proper frequency.
Now, switches look for changes in impedance fro mline to ground to detect an off hook. Party lines are pretty much out of the picture, though subscriber carrier systems manage to perform a similar task. But somewhere out there I am sure there is some old equipment still in use. Phone companies don't throw anything away! You often see 60 year old equipment still in use in rural areas.
The phone network guarentees a quality of service, so there's a sharp cutoff to how many simultaneous users there are. If a trunk group is designed for n users then user 1 through user n will each get an 8kbps pipe but users >n get a fast busy. Conversely, if there are less than n users those users don't get better service.
The internet has no such guarentee, so as traffic increases it degrades. So if the path is designed for decent response for n users, the n+1 user still gets on but all users from 1 through n+1 get slightly degraded service. If there are less than n users then service is generally better than the standard.
It seems that they'd be better as an accessible source of raw materials. Metallic asteroids of iron & nickel, ready made stainless steel. Rocky asteroids provide soil, probably water & other organic materials. The comets would be an amazingly rich source of organics & water. Accessible because you don't have to drag them out of a deep gravity well. Launch from earth, with just enough materials & people to make it to an asteroid. Use that as a bootstrap, use the asteroid's material to make a basic habitat ... perhaps sell the high value items (precious metals, or will water & fertilizer be more valuable soon?) to fund interim supplies, including workers, from earth.
Eventually get a minimg colony that can feed itself & also launch terraforming supplies to planets. Drop metals, water, organics for fertilizer toward Mars. Form a heavy metalic container, fill it with water, soil, fertilizer. Then cover it all in the slag left over from processing. The slag will burn off as the package drops through the atmosphere. Then you have the contents of the container as well as the metal container to recycle.
That hapenned on my '94 GMC. Not a software bug. The truck has a plenum/hose that leads from the air filter to the intake manifold. Halfway there is a mass airflow sensor. At the intake manifold is a butterfly valve attached to the throttle via a linkage with a spring. The air can suck the butterfly valve open a bit more. I had the same symptoms you described, it started after the car warmed up. What I found was a tear in the hose between the sensor & the butterfly valve. When cold, the engine computer runs open loop. It measures the air being injected (via the sensor) and injects the proper amount of gas for a good fuel-air mix. Step on the gas, open the butterfly valve, more air, more gas, more go. With the tear, there was more air getting in to the engine. It wasn't flowing past the sensor so too little fuel was used, the mix was lean. Good enough to run, though. It gets interesting when the engine heats up, then the engine computer goes closed loop. It measures the pollution in the tailpipe (more sensors). Too many hydrocarbons and it leans the mix, too much NOx and it injects more fuel. So with the torn hose, once the engine warmed up the engine computer startd increasing the amount of fuel until I was idling at 35 MPH. Some tape by the side of the road was a temporary fix. Some time puzzling through manuals at home, out of the rain, gave me the explanation.
What about the systems that the cabs used?
Also, almost everybody has new cell phones with GPS capability. So you're jammed in the cab with 3 Japanese and they've all got their mobile phones out with route maps & current position shown. Heading north through Yokohama there was severe congestion (no, just normal rush hour congestion, I was told). Now everybody is telling the driver what he should do.
The only thing anything worse than a carload of backseat drivers is a carload of backseat drivers with too much data.
I had watched the driver pan his display. It doesn't matter how much data you have, when everything is congested there is nothing you can do. We can't go forward, we can't go back, we should've stopped for a couple of sakes.
OK, after much discussion it was decided we'd use surface roads. These were congested too. The congestion data was only for major roads & highways. OK, so it didn't help. At least we aren't moving any slower than on the highway. The scenery is different, waterfront, docks, warehouses ...
Wait! There is one person beating the traffic. Our cab was being passed! A woman on a bicycle -- steering with one hand while holding her mobile phone in front of her face with the other. Staring at her map.
Anything else and you put yourself and innocent bystanders in danger.
I was in California a few months ago, on a business trip. The topic of discussion was a homeowner on trial for attempted murder. Somebody broke in and threathened the guy, said he was going to beat the crap out of him. The homeowner had a gun -- legally owned it. He pointed it at the intruder and, when the guy still advanced & threatened him, the homeowner shot the guy.
The prosecuter said this was unecessary force. The intruder was unarmed and the homeowner shouldn't have used a gun.
I guess he was supposed to sit there and let the bad guy beat the crap out of him!?
So even if you do everything right, you don't get caught by a phish, you'll still be paying. A portion of losses caused by others getting duped will be added to your fees and/or reduce value you recieve. The companies will pass the cost along to everybody & protect their bottom line.
Cheap silicon wins again -- it's been supplanting copper, now optics.
No -- I took off my glases and it's all the same.
Where do I sign up?
We finally found what his job was when government auditors showed up. He was the company scapegoat. He got 9 months off work -- with pay. Within a month of coming back they announced he was retiring -- golden parachute, full pension.
I wanted that job!
An easy thing to do was combine several elements into a single tube. That meant a single power-hungry filament could support two triodes and/or pentodes, and possibly also a couple of diodes.
The circuit designs used were more interesting. A Motorola lunchbox-sized AM radio was made with 3 tubes. I remember one tube contained a pentode that was used as an RF amp, IF amp and first audio amp. They used a summing junction to sum all the input signals. At the output they used filters to seperate the three bands of frequencies.
Monopoly has a lot of definitions, not all of which apply in all cases. Walmart often has a monopoly in a market area. They drive out the Mom & Pop businesses in small towns, removing any competition. In the area I live, central NJ, there are enough people that they their tactics aren't completely effective. But small towns, isolated from larger metropolitan areas, are areas that they have certainly been able to gain a monopoly.
You could change options like price, delivery & support. The app had algorithms that scored your bid against the rest. The points for technical capabilty were determined from previous trials & fixed.
It was scheduled for 2 hours, with half hour extensions if there was a change by one of the top 3 in the last 5 minutes. The business would be split by the top 2 bidders -- we were trying for the #2 spot to maximize our revenue.
At the end (after half a day of this game!) we were surprised to find we were in the #1 spot. The company that we had expected to come out on top, that had been for most of 12 hours, didn't get any business. We found out later that the guy at the keyboard had had a heart attack and they dropped to #4.
A few years ago, where I used to work, I noticed a secretary using the copy machine on our floor. She was from legal & their machine was broken. She was making copies of a 4 inch stack of email printouts.
Her job was to print all of the emails her boss got, stamp them with a date, then make copies. One copy got filed, the other read by her lawyer boss. She'd then respond to emails per her boss's scribbles, file the annottated hardcopies, print the responses, time stamp & file them.
I wonder how this guy would handle gaming online?
This could be a poll question. If you're married, what was it that you really wanted:
A. laid
B. blow job ...
I can't believe how many times I've heard a newlywed engineer say: "All I wanted was ".
The only part of the network that may not be VoIP might be the local loop. That is, they might combine your VoIP traffic with your internet trafic. But at the CO filter they'll out the RTP packets, sanitize them, and send them over their private network for the long haul.
The goal for them isn't to share voice & data (they've been doing that over the switched network for decades) but to reduce the cost of maintaining the network. An IP network is, to some extent, self healing & self routing.
It wasn't pretty.
Expensive doesn't mean good. Get an inexpensive Pelikan, about $20.
Most of my work is via keyboard, PDA entries on a touchscreen, but for taking notes a fountain pen is still the best. A gentle grip, minimal pressure, light weight, I can take notes rapidly and for extended periods with without fatigue.
Color tubes restrict how you can mount them. The guns are either arranged in an equilateral triangle (point up) or in a horizontal row with a pattern of red, blue & green phosphors to match.
Monochrome tubes give you a lot of options. Only one gun centered in the neck. No pattern of colored phosphors on the screen. It's all white so it's just spread inside the front of the tube. You can rotate the tube anyway you want, giving you infinite possibilities if it's round.
Old B&W TVs with round tubes made use of this. Most components were on a chassis at the bottom so it isn't top-heavy. Tuner & other controls somewhere near the top so it's easy to reach. Tube rotated to the side opposite the tuner so it's away from everything -- usually a bit above horizonal because the HV power supply will be at that end of the chassis & it's rather large.
256 bit WEP? Only a couple of manufacturers support it.