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Comment Re:Comcast customer here (Score 1) 111

I had @Home cable modem service and it was taken over by AT&T. This was around 1999 and AT&T in their infinite wisdom decided that 1Mbps upstream bandwidth was too much, so instead of programming the modems to throttle lower they decided to do it at the head-end where they throttled the aggregate bandwidth of all of the subscribers on a node down to 128Kbps. This meant that ALL upstream traffic from all customers on the node combined was limited to 128Kbps. At the best of times I only saw 40% packet loss. I couldn't even download email much of the time (and their spam filter was pretty bad). It was like this for 9 months. Calls to support said to reboot the computer and power cycle the modem. A simple traceroute showed exactly where the problem was and it was in their network and had nothing to do with my end.

I was paying somewhere between $60-80/month in 1999 for this crappy service. AOL Dial-up was faster since I often saw 20Kbps or lower downstream bandwidth due to the upstream throttling. Then Comcast took over. Instantly the network was MUCH better. It's been more reliable and they got rid of the ridiculous caps. I also had numerous issues with AT&T billing and their email server was often down or unusable (even not counting the bandwidth cap problem).

Comment Re:Comcast customer here (Score 1) 111

My experience with Comcast vs AT&T is day and night. AT&T took over the cable system and @Home in my area and it became unusable because of AT&T's screwups. They throttled the aggregate upstream bandwidth of all of the customers on a node to 128Kbps. That's like myself and all of my neighbor's traffic combined being limited to 128Kbps upstream bandwidth. Their support would ask me to reboot my computer even though a simple traceroute or ping showed exactly where the problem was, and it was on their network. It was like this for 9 months. Dial-up was faster than AT&T at the best of times.

Having designed DSL head-end equipment I'm surprised it works as well as it does, especially when they throw crap like PPPoE on top of it. Oh, and if you think Comcast support is bad, it doesn't hold a candle to how bad my experience was with AT&T. Hell, I'd pay double the rate on my cell phone than have to give another cent to those incompetent bastards.

Having seen a friend's AT&T DSL (not U-Verse), I wouldn't touch it.

I now have Comcast business... it's like what my original @Home Internet was like, the downside being it's expensive.

Comment Re:Comcast customer here (Score 1) 111

From my experience Comcast is infinitely better than AT&T. Originally I had @Home Internet service which was great. In the 1990s I was getting 10Mbps full duplex which was unheard of. Later they reduced it to 1Mbps up and 10Mbps down and I was still happy since the alternative was dial-up. Then AT&T took it over as ATTBI. AT&T in their infinite wisdom figured that 1Mbps upstream was too much so they cut the upstream speed to 128Kbps. To make matters worse, they didn't cut each customer's upstream bandwidth to 128kbps, they throttled the AGGREGATE bandwidth of all the customers on a node to 128kbps. In other words, they took all of the customers combined on a segment and throttled the combined bandwidth to 128kbps. That meant that at the best of times (like 3am in the morning) I would only see a 40% packet loss with ping due to the throttling. It was inanely bad. Even email was impossible. With their bad spam filters my email client couldn't even keep up with the load due to the horrible performance. Dialup was much faster because of this. It was like this for around 9 months, then there were the billing problems on top of that. The best that AT&T support could offer was to reboot the computer or claim it was because I wasn't running Windows. As a network engineer it was obvious to me where the problem was. A simple traceroute pointed to exactly where the packet loss was happening.

When Comcast took over it was like a breath of fresh air. As bad as Comcast was they couldn't hold a candle to how bad AT&T was. Comcast ended up upgrading all of the cable infrastructure and immediately fixed the caps and the tech support, while nowhere near as good as it was with @Home when I started with them, was at least an order of magnitude better than AT&T. I don't know if anyone can beat how bad AT&T support and billing was. I will NEVER deal with AT&T again.

I have since switched to a Comcast business account. Other than the high price I'm paying I don't have any complaints over it other than the fact that for IPv6 I can't get anything better than a /64. You can't subnet a /64.

After having designed DSL equipment I'm surprised it works as well as it does, especially when they throw crap like PPPoE at it. The original Redback documentation I had said PPPoE was designed to "preserve the dial-up experience". Then you had companies like Microsoft who would screw up PPPoE (they turned on PPP header compression which is not recommended which would result in unaligned packets which could have a significant performance impact on head-end equipment). The PPP header compression saved 1 byte in the packet, but it was useless because the MTU still remained 1492 bytes and with the overhead of ATM it never saved any bandwidth, but resulted in the payload being unaligned within the Ethernet packet.

Comment Re:Not to rain on the parade, but... (Score 1) 198

I have almost 50K miles on my Tesla Model S (P85) and have not noticed any loss in range. The general consensus is that there is less than 5% loss in range after 100K miles with the 85KWh battery pack. The batteries are not the same as those used in cell phones and are much more rugged. I spend $50/month ($0.12/KWh) on electricity and drive around 1000 miles/month with most of that charging being at home. It's a big car, so I'm spending a fraction of what I'd spend on gas for a similar car, especially a car with similar performance. My brake pads don't get a lot of use, there's no transmission, fuel pump, fuel injectors, belts or oil changes to worry about (motor is lubricated for 12 years). Mechanically my car's drive train is much simpler than any ICE car. As you said, the price per KWh for batteries is dropping fairly rapidly. I expect that if I end up needing to replace my battery I'll end up with a bigger battery than what my car came with with the price being quite a bit less than what was quoted when I bought the car. When Tesla gets their battery factory going full bore they expect to drop the price by another 30%. Already Tesla is leading the industry in terms of lowest cost/KWh.

There are a few things in common with an ICE car such as electric power steering, a cooling system which in some ways is more complicated but handles far less heat than an ICE car, climate control, etc, but in general it's much simpler. One just needs to look under the hood and see the huge amount of space where the big monstrous engine and transmission is missing. I don't think you can get more reliable than an induction motor either since there aren't even any brittle magnets full of rare-earth metals to be demagnetized.

The only maintenance I need to worry about is rotating and changing the tires, wheel alignments, changing the cabin air filter and wiper blades. Even the brakes should last longer. Eventually I'll have to get a lube job on the motor... at 12 years. I suppose the coolant and brake fluid also needs to be changed at some point, but I don't have to do regular oil changes, change the fuel filter, engine air filter, belts, etc.

Comment Re:Umbrella for the parade (Score 1) 198

There are a lot of safety systems in these charging systems where they monitor the temperature of the connectors, the voltage loss between the charger and the car (to detect bad connections) and probably GFCI as well. With my Tesla model S it always starts out slow and ramps up the current draw and monitors the voltage sag and other characteristics to shut down if it detects a problem. No high voltage flows until both the car and charger finish negotiating. If the cable is suddenly unplugged then the power is shut off. It is probably a lot safer than filling a gas car though I did see a case where a Tesla was charging when lightning hit it.. While the car certainly was unhappy I can imagine lightning striking a car filling with gasoline could be much worse.

Comment Re:I call BS (Score 2) 198

The problem is that you chose the Nissan Leaf, which is probably the WORST EV out there due to poor battery management. There is no active battery cooling and they tend to cook themselves to death. Also, having a small battery like the Leaf means it will cycle a lot more for the same number of miles compared to cars with larger batteries. The cycling and heat is what kills them, plus charging them up to 100%. Also, Nissan made a poor choice when it came to their chemistry and hence their batteries did not hold up.

Numerous Tesla Model S's have surpassed 100,000 miles and battery degradation is typically under 5% capacity loss and is generally not noticeable. They have since improved the batteries further so the newer batteries should last even longer. Tesla also has by far the lowest price per kwh for their batteries and it should drop by at least another 30% with their new factory coming online.

Comment Re:I call BS (Score 1) 198

It certainly is cheaper with modern batteries. With the Tesla model S people have already put over 100K miles on the car and they're seeing less than a 5% loss of range. I'm at about 50K miles in mine and have not noticed any reduction in range or performance. The batteries are rated for 3000 charge/discharge cycles which equates to well over 600,000 miles.

Mechanically the system is far simpler than an ICE car. There are far fewer moving parts. The motor is lubricated for 12 years, instead of every 6 months and 5K miles. There is no transmission, no spark plugs, no belts, fuel pump/filter, etc, nor the huge myriad of other moving parts. There's no head gaskets to go, timing belts to slip, no piston rings, fuel injectors, catalytic converters, oxygen sensors, etc. There is a cooling system, though it is dealing with far less thermal stress than a gasoline engine.

Another thing is that the cost of running the car is a lot cheaper. I pay $50-60/month for electricity (at $0.119/kwh and drive around 1000 miles/month, and this is a big car and I don't drive like a grandma either. None of my power comes from coal. Most comes from natural gas, nuclear, hydroelectric wind and solar and a bit of geothermal, plus I have solar on my roof. As time goes on the grid is getting cleaner, since it's actually cheaper now to install wind or natural gas compared to coal, which is growing more expensive as all the large seams are used up. Also as time goes on the electric grid gets cleaner as older plants are shut down and replaced with more efficient plants that burn more cleanly. In fact, today a lot more coal plants are being shut down than are being built. Natural gas is cheaper and produces half the CO2 and a fraction of the other nasty stuff coal plants have to deal with and wind is now cheaper still in many places.

This chart from here shows how things are changing. Notice the very rapid shift in recent years.

My previous car was a Prius. It's still going on after 10 years with the original NiMh battery pack, and the Prius cycles the batteries a lot more than my Tesla does. In the almost 4 years since I've bought my car they've improved the power density, reliability, performance and reduced the cost quite a bit. My P85 is now available as a P100D (100KWh in the same form-factor as the 85KWh battery in my car). The electric motor has no brushes to wear out nor even any rare-earth magnets to worry about, being an induction motor. Even the brakes get quite a bit less use than those on an ICE car since much of the braking power goes into recharging the battery.

As far as regular maintenance the only things that need to be dealt with are:
- changing cabin air filter
- change wiper blades
- check/change brake fluid
- check/change brake pads (far less frequently)
- change coolant (though far less frequently)
- wheel alignment
- rotate tires
- replace tires

All of these are similar to a gas car, though notice what's missing.
- No engine air filter
- No oil changes
- No timing belt or any belts
- Less brake maintenance
- No power steering pump (electronic, though more gas cars are doing this now too)
- No engine-driven AC compressor to start leaking (sealed electric compressors tend to last a lot longer)

Notice I didn't say anything about the battery. The battery is under warranty for unlimited miles, 8 years, though I suspect it will last a lot longer than 8 years, and when it comes time to replace it, the cost keeps dropping, not increasing. EV car batteries are not the same as cell phone batteries and they're not treated like cell phone batteries. Cell phone batteries are optimized to be thin and as much capacity as possible, then when you charge your phone it usually charges it to 100%, which is very hard on the battery. EVs typically don't charge over 90%. While I can charge my car to 100%, it's very rare and typically I only charge to 70-80%.

Comment Re:What a waste (Score 1) 61

That's my feeling as well. They claim up to 90% efficiency if you park just right, but a cable is a lot more efficient. When I'm charging at 20KW (as I can do in my garage), I don't need a 2KW heater as well. Normally I charge at 10KW since there's a lot less line loss. I see an 8v drop between my meter and my charger when charging at 20KW. Though the cable gets warm I don't see any significant drop between the charger and my car. Just charging at 80A means I'm wasting 640 watts as heat in the 100 foot run between my meter and my charger. At 40A the loss is negligible between my meter and my car.

Also, by plugging in I don't have to haul around the extra weight needed for inductive charging.

It takes me 5 seconds to plug in at night and 5 seconds to unplug my Tesla in the morning.

Also, inductive charging really wants you to park just right. Given how I see people park, I doubt it would work all that well for a lot of people.

Comment Re:Set speeds will follow autonomous vehicles. (Score 1) 162

In San Francisco from what I've seen the bike lanes are very well marked. It sounds like the thing Uber is most upset about with getting a permit is that they need to report every incident. Also, from my research it sounds like Uber has a long way to go with their system. Given the high population density and lack of parking and high cost in San Francisco, bicycles are a popular alternative.

Comment Re:Is this always the safest? (Score 1) 162

They can accumulate data with autopilot turned off. The hardware is not designed to fully handle undivided roads which is why they're doing this. The new hardware and the next major release should fix that, but not for cars manufactured before October 2016. More data from the older cars won't help when they lack the necessary sensors.

Comment Re:Is this always the safest? (Score 1) 162

This is a case where Tesla is trying to discourage people from using Autopilot on undivided roads. The current autopilot system is not really designed for the way people are using it. It does not detect stop signs or red lights. It is designed mostly for divided highways. The next generation, Autopilot 2.0, is designed with undivided roads and full autonomous driving. All of the currently shipping cars ship with the hardware for this but lack the software which is still under development.

If you want to drive above the speed limit on undivided roads, don't use autopilot, it's as simple as that. Nobody is forcing anyone to use it.

Comment Re:Set speeds will follow autonomous vehicles. (Score 1) 162

That looks like one of the Uber cars. SF and California are pissed that they did not apply for a permit like everyone else for testing their vehicles and that their cars are blowing through red lights and making unsafe turns.

Tesla is fairly specific that they are currently not L5 autonomous. They really don't want people to use autopilot on undivided roads. If you want to go fast, don't use autopilot, it's as simple as that. The current autopilot is best used on divided highways and freeways since it doesn't understand things like stop signs or stop lights.

The new cars come with a much more comprehensive set of sensors so that they will be capable of fully autonomous (L5) driving in the future but the software is not ready. The new system has a lot more cameras and radar capability.

Here is a video showing Tesla's autopilot 2.0.. The neat thing with this video is it also shows what the autopilot system sees and identifies. You can see the autopilot stopping for pedestrians jogging by the side of the road, for example, as well as stopping at red lights and stop signs. Granted, this sort of driving is far less complicated than driving in San Francisco.

Driving in SF is not for the faint of heart if you are not used to it. It's easy to get lost with the one-way streets, especially if your GPS gets lost due to the tall buildings (a common occurrence). With the bicycle lanes and lots of crazy rules and having to dodge double-parked vehicles and pedestrians I've found it to be one of the most difficult places to drive. It seems that Uber's engineers are not taking things seriously when their test cars make these mistakes. In order to test an autonomous vehicle a permit is required. All of the other manufacturers who are working on this managed to go and get the proper permits so I see no reason why Uber doesn't. Uber seems to generate a lot of controversy and is frequently subject to lawsuits because they feel they can do whatever the hell they want. I have friends who drive and they much prefer driving for Lyft because they treat their drivers a lot better (like making it easy for passengers to give tips).

Here's an aricle talking about how Uber's cars illegally cut into bicycle lanes. SF tries to be a very bike friendly city. The way the bike lanes work there is that near a right turn they move left so that the car turning right is in the far-right and the bike lane is between the right-turn lane and normal traffic. That way, cars making a right are less likely to suddenly cut off bicyclists.

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