If you're doing your RSS smart, and generate static pages to be server while checking and sending proper conditional headers, then it really doesn't require that many resources.
Or if your XML server has proper caching system, like AxKit which I use to make my simple weblog software AxBlog.
I assume you are the same Bev Harris who is a major activist in this area. If that's the case, then I congratulate you on your work so far. I have to address this to you publicly since you don't have an email address or website listed in slashdot.
I didn't get karma bonus on slashdot by being a whore for the voting machine industry. I think you can be fairly sure that voting machine industry people would be slapped down pretty hard around here. FYI. maybe if you included a little more positive and less reactionary response that would be better.
This is a prepared talking point sent out by the voting machine industry.
Err... yeah... because I'm employed by the voting machine industry, it's a conspiracy...
I wonder if you read my message again if you will find anything in it on the subject of whether or not the machine should or should not print out paper. No, you will not. However you will hopefully have noted that the old style pen and paper system while it has three advantages (it's simple, simple and simple) isn't as accessible as a touch screen.
Any debate should bear in mind that thought. It is a valid reason to throw away fair elections? No. But if it's possible to make voting systems that are as secure as paper, and use touchscreens, that would be an overall improvement over just paper.
the reason that they want electronic voting is because it gives access to the disabled, who can push a touch-screen button but can't use a pen and paper.
Apple had a period during 1995-1998ish when their computers weren't particularly reliable compared to PCs. Personally I almost dumped the Mac but then Jobs returned to the company and things have gone back to the good old days as far as Mac reliability. These days they "just work".
These days, any hardware since the G3 came out has been rock solid, and Mac OS X is also VERY low maintenance. I run OS X 10.2.6 on my TiBook and get week-long uptimes between reboots.
Every IT dept I've ever encountered was overburdened to start with. I can't imagine they would not want a break so they could attend to more important things than Windows crashes. Not only that, but the techs _hate_ dealing with this stuff.
If you _hate_ dealing with this stuff, why don't you quit?
IT is like a priesthood. Only the priests understand the computers, so they have this absolute control over the decisions that upper managements makes. You think that the president has any clue what to do about IT? Hah.
So, yeah, IT people like Windows because it keeps them in a job. And Microsoft feeds right into this. Ever noticed how there's ALWAYS a workaround in Windows/Office/whatever? There's almost always some way to get the software to do what you want, even if it means hours of registry hacking or whatever. Microsoft probably makes sure that every bug in their database is resolved to at least "Workaround exists" status and then they ship it.
Linux is also happy for IT depts because it's infinitely configurable.
Apple, on the other hand, makes systems that are designed to NOT NEED ADMINSTRATORS. Thus, it follows that no system administrator will ever buy one.
THat's why apple doesn't have much chance of breaking into the corporate market, frankly.
Her regional office received a call in the late morning from central office: "Turn off all the computers. Don't turn them back on until we call you again".
Needless to say, she isn't getting much work done.
Er, actually I'm surprised that people on slashdot are so surprised. I mean, we all had to expect that the GPL would be tested in court eventually, right? And that when that finally happened, it would basically be a big deal.
I got one of these models (actually a previous one the HBH-30) so it's good to see it got highest marks. Actually I don't have a bluetooth phone, I have a mac and I wanted to use it with the voice chat programs like ohphoneX or I guess iChat now.
Anyway, bad luck, OS X doesn't support the right connection mode yet (SCO synchronous connection-oriented) although at the WWDC they hinted that it would be in the next revision IIRC. Until then I'm SOL or looking for other options, I don't really feel like learning how to write an IOKit driver at the moment. So finally I hear about this nifty gadget here and reviewed here which will basically let you connect a bluetooth headset to any kind of 2.5mm jack equipped cell phone / portable phone.
Not quite good enough I'm afraid but actually I figure it will be easy enough to convert the 2.5mm headset jack into two separate plugs (one for mic other for headphones) and plug them into the right jacks in my TiBook. Some instructions are on this discussion board, but actually I think that I might just buy one of the older "hands free car kits" that work through the cassette deck (such as this one or this other one since they're dirt cheap. I'll just splice the casette cable into a regular 3.5mm (aka 1/8") jack. Or whatever. I'm sure radio shack can supply the necessary parts.
Then I'll be able to use my headset with anything! My computer, my camcorder:) hell, maybe I'll dig up a 2.5mm adapter for my ancient but still cool StarTac:-) Why limit yourself to cell phones?;-)
You could double your bandwidth at the HillsHub immediately by installing another waveguide, polarized perpendicular to the current one, and on a different non-interfering channel. In australia there's 3 non-interfering channels.
You acknowledge on your page that you are introducing greater latency. Latency is another bugbear of the 802.11 QoS crowd, because it affect voice applications. 802.11 latency also goes way up when the hidden node problem occurs. Again with that situation, increasing bandwidth will solve the problem.
In addition, you said in another post that you collected $150 each --- money that could be spent to install new hubs and/or higher bandwidth hubs.
I'm not dissing your efforts, I think CWNs are great. But there is a broad group of people who think that QoS is needed everywhere, Wi-Fi, in IPv6, etc., and it's bad news.
Score another point for Wi-FUD. That is ONE solution but not the ONLY solution. You could of course, also reduce contention for the shared medium by installing multiple hub radios with sector antennas and save a lot of money.... until a given sector gets overloaded. then you are back at square 1. Phased arrays are much more resilient as their beams are much, much more directed.
Hmm.. I thought we were trying to solve the original problem. If you're going to keep piling nodes onto the hub, you're going to hit limits whether you use the 1-5 gigabuck standard or the 10-100 gigabuck proprietary system.
Yeah, because 802.11g and 802.11a use a completely differnt MAC right? wrong. they have the same problem. its just less pronounced because you have more bandwidth.
Umm.. yes, you're right, that's exactly my point. The problem is solved by upping the bandwidth, instead of fiddling around with complicated MACs.
Sorry, the 802.11 MAC is a pile of crap full of inefficiencies in the name of simplicity and cheap implementation. Things like full duplex, smarter rate management, better CA mechanisms, all have vastly more potential for increasing throughput than simply jacking up existing bit rates with the 802.11 MAC.
I never saw a simple and cheap solution I didn't like. Jacked up bit rates? Bring 'em on. I'll be running at new speeds by the time you get QoS working at the original rate...
No, I'm sorry, you're wrong. See my rant and specific responses below.
In wireless the problem is even more pronounced in infrastructure mode because you are using CSMA/CA -- collision avoidance. This means that for every packet to be sent, the clients must coordinate use of the medium before sending, using a RTS/CTS handshake.
Actually CSMA/CA does not include handling of hidden nodes. RTS/CTS was specifically ADDED to 802.11, AFTER CSMA/CA was decided, to handle the hidden node problem.
When you put many clients (20+) on the same AP sharing the same medium, a large amount of bandwidth is spent simply coordinating contention free access to the wireless medium itself.
There is mutual interference between hidden nodes during the RTS/CTS phase.
The only true way to prevent this kind of inefficiency for larger numbers of clients is to use a true wireless phased array switch, like vivato, which can effectively emulate a dedicated medium to each client, preventing any contention that arises in the broadcast CSMA/CA situation.
Score another point for Wi-FUD. That is ONE solution but not the ONLY solution. You could of course, also reduce contention for the shared medium by installing multiple hub radios with sector antennas and save a lot of money. OR, you could upgrade to a faster wireless standard like a or g, and eliminate the contention altogether!
In fact, despite the attempts for people introduce "Quality of Service" measures (which is exactly what fropple or whatever it's called really is), ethernet (10,100,1000MB... and more?), the internet, and dare I say it, Wi-Fi continue to work VERY VERY well based on the model of "best-effort access". Yes, they all degrade rather substantially when put under heavy heavy loads. BUT, the solution is to INCREASE available bandwidth, which leads to new possibilities and innovations and solves the old medium access contention problem at the same time.
First, what the heck is the hidden node problem anyway? It's highly misunderstood. The hidden node problem is when you have a point to multipoint topology in your 802.11 network, aka, a "star" topology. There is one central hub that is connected to the internet, and many nodes that talk to the hub. Now this is all fine and dandy indoors, because indoors usually all of the nodes can hear not just the hub but also each other as well. So they are effectively sharing a single bus, and they can listen to find out if anyone else is using the bus before they talk (classic CSMA situation right?)
Problem is outdoors. Outdoors, you're using long-distance antennas on each of the nodes and an omni on the hub. Now the nodes are mutually deaf, because all they can "see" is the hub, they are too far away from each other to "hear" each other. Thus, they hidden from each other. Now, they cannot perform the Carrier Sense part, because when they listen on the bus, they will not be able to hear if another node is in send mode, sending data to the hub. They will not hear that, and they will decide to broadcast, and the hub will get spammed with two signals at the same time. That's the hidden node problem.
Well there's already a partial solution to the hidden node problem built into 802.11. It's the RTS/CTS system. RTS is Request to Send. Before any node starts talking, it sends a query to the hub, asking if it's all clear. The hub ACKs with a CTS (Clear to Send) response. ALL of the nodes can hear the CTS, so they all delay their own transmissions for a little while.
Of course, you can still have undetectable collisions during the RTS/CTS period! But that's OK, because USUALLY the bandwidth that the hub is CAPABLE of handling FAR exceeds the bandwidth that the nodes NEED. In fact, if you are experiencing the hidden node problem, you can just use TCP throttling to reduce the problem substantially.
We know that the hidden node problem is directly proportional to the percentage of the bandwidth being used. At this point we must say, quite frankly, that the BEST solution is to INCREASE the bandwidth available! Thus, not only do you REDUCE congestion but you also INCREASE speed.
Token ring totally pisses me off. Sure, it's a great idea. You put everyone in a circle and you give one of them a "token". Only the dude with the token is allowed to talk. When they're done talking, they pass the token to the next person, and so on, around the circle, until it comes back and you start again. Great idea in theory.
The problem is there's so many failure cases. What if one node hogs the token? What if a node drops the token? How do you recover from that? What if just one section of the circle dies? When a new node comes online, how do you add it to the token ring? There's a ton of central control required, and that means (a) complexity and (b) overhead and we know that both of those are BAD news.
All that is R&D effort that's totally wasted because all you're doing is making the current system work, that energy could instead be spent on installing a faster model that doesn't get congested in the first place.
Have a look at Dan's paper "Why We Don't Need QOS: Trains, Cars, and Internet Quality of Service" before you start clapping.
I think the answer is clear: Go for more capacity rather than handling the narrow advance from dealing with congestion. That's what worked for Ethernet.
802.11a/g are at 54 Mbps, who knows what the next jump will be.
Are you kidding? 22ms is great for voice chat. Think about it... You're talking about 1/50th of a second here. You really can't tell, trust me.
The main culprit in VoIP latency is really jitter. That's basically packets that arrive out of order or don't get there and need to be resent. If you've got a lot of jitter it drives up the latency to compensate (the codec needs time to reassemble them in the right order). It's better often just to drop missed packets... there's lots of work in this area.
Jitter is usually caused by congestion. So, as long as you aren't saturating the link, you should be fine with 22ms:-)
When you're living on a dollar a day, copper is a VERY valuable substance. It's pretty trivial to extract and melt down the copper, once that's done you can't tell if it's stolen or brand new. Easy to launder it back into the normal economy.
South Africa is running a lot of fibre now because, unlike copper, it has no resale value.
I was just reading about telecomm in Africa. Somalia and DRC are both doing GREAT in terms of telephone and internet access. The call prices are far cheaper there, there's more competition, and the business is healthier. Both countries are TOTAL DISASTER AREAS otherwise.
So what's up with that? Turns out that the traditional telephone company model that worked so well for 50 years is now crap. A single state-owned telco simply can't keep up any more. Most African countries kept the state telcos as monopolies even if they did sell them off (so they're private monopolies now) and where there's a monopoly in telephone there's bad service, overprices calls, and an underground market in (usually VSAT-based) IP telephony at cut-rate prices.
Noble intentions perhaps, but many of the world's problems have nothing to do with technology, so it seems wierd to me to try to use technology to solve them.
Drinking water? How about food from your crops. If you can't talk to an Agricultural expert who can advise you on what to do about the weather, the latest seeds you're getting, the changes in the environment, you might not be eating this winter.
If your water was bad but you can't talk to a doctor about what your symtoms mean, you might treat it with the wrong medicine.
If your kids can't learn because the good teachers in the city don't want to travel over bumpy, muddy, washed out roads, they won't be able to lift themselves up by the bootstraps.
Why do the people of Slashdot ask dumb questions without reading the article?
Since you're probably long gone I'll summarize for you:
0. In rural India, it's often really hard to get to places due to very poor roads, that get washed out in the rain, and the population is very broadly distributed on farms.
1. A teacher in the city can educate children in a rural area. (viz., telecommuting)
2. Doctors can run virtual clinics for villagers to give them medical advice.
3. Scientists can have meetings with local farmers to give them crop advice.
All of these things are IN DEMAND by the people who had a chance to try them out.
Slashdot Mirror
Thank god.
I'll be happy not to have the computers tracking my face thank you very much. Too much of a pkdick idea I think.
But what about the system installed in London, England?
simon
Or if your XML server has proper caching system, like AxKit which I use to make my simple weblog software AxBlog.
simon
Bev,
I assume you are the same Bev Harris who is a major activist in this area. If that's the case, then I congratulate you on your work so far. I have to address this to you publicly since you don't have an email address or website listed in slashdot.
I didn't get karma bonus on slashdot by being a whore for the voting machine industry. I think you can be fairly sure that voting machine industry people would be slapped down pretty hard around here. FYI. maybe if you included a little more positive and less reactionary response that would be better.
simon
just curious, what do they do for people who are blind? Do they have special braile ballots or whatever?
simon
Err... yeah
I wonder if you read my message again if you will find anything in it on the subject of whether or not the machine should or should not print out paper. No, you will not. However you will hopefully have noted that the old style pen and paper system while it has three advantages (it's simple, simple and simple) isn't as accessible as a touch screen.
Any debate should bear in mind that thought. It is a valid reason to throw away fair elections? No. But if it's possible to make voting systems that are as secure as paper, and use touchscreens, that would be an overall improvement over just paper.
simon
the reason that they want electronic voting is because it gives access to the disabled, who can push a touch-screen button but can't use a pen and paper.
simon
Apple had a period during 1995-1998ish when their computers weren't particularly reliable compared to PCs. Personally I almost dumped the Mac but then Jobs returned to the company and things have gone back to the good old days as far as Mac reliability. These days they "just work".
These days, any hardware since the G3 came out has been rock solid, and Mac OS X is also VERY low maintenance. I run OS X 10.2.6 on my TiBook and get week-long uptimes between reboots.
simon
If you _hate_ dealing with this stuff, why don't you quit?
simon
IT is like a priesthood. Only the priests understand the computers, so they have this absolute control over the decisions that upper managements makes. You think that the president has any clue what to do about IT? Hah.
So, yeah, IT people like Windows because it keeps them in a job. And Microsoft feeds right into this. Ever noticed how there's ALWAYS a workaround in Windows/Office/whatever? There's almost always some way to get the software to do what you want, even if it means hours of registry hacking or whatever. Microsoft probably makes sure that every bug in their database is resolved to at least "Workaround exists" status and then they ship it.
Linux is also happy for IT depts because it's infinitely configurable.
Apple, on the other hand, makes systems that are designed to NOT NEED ADMINSTRATORS. Thus, it follows that no system administrator will ever buy one.
THat's why apple doesn't have much chance of breaking into the corporate market, frankly.
simon
Her regional office received a call in the late morning from central office: "Turn off all the computers. Don't turn them back on until we call you again".
Needless to say, she isn't getting much work done.
simon
Er, actually I'm surprised that people on slashdot are so surprised. I mean, we all had to expect that the GPL would be tested in court eventually, right? And that when that finally happened, it would basically be a big deal.
simon
I got one of these models (actually a previous one the HBH-30) so it's good to see it got highest marks. Actually I don't have a bluetooth phone, I have a mac and I wanted to use it with the voice chat programs like ohphoneX or I guess iChat now.
:) hell, maybe I'll dig up a 2.5mm adapter for my ancient but still cool StarTac :-) Why limit yourself to cell phones? ;-)
Anyway, bad luck, OS X doesn't support the right connection mode yet (SCO synchronous connection-oriented) although at the WWDC they hinted that it would be in the next revision IIRC. Until then I'm SOL or looking for other options, I don't really feel like learning how to write an IOKit driver at the moment. So finally I hear about this nifty gadget here and reviewed here which will basically let you connect a bluetooth headset to any kind of 2.5mm jack equipped cell phone / portable phone.
Not quite good enough I'm afraid but actually I figure it will be easy enough to convert the 2.5mm headset jack into two separate plugs (one for mic other for headphones) and plug them into the right jacks in my TiBook. Some instructions are on this discussion board, but actually I think that I might just buy one of the older "hands free car kits" that work through the cassette deck (such as this one or this other one since they're dirt cheap. I'll just splice the casette cable into a regular 3.5mm (aka 1/8") jack. Or whatever. I'm sure radio shack can supply the necessary parts.
Then I'll be able to use my headset with anything! My computer, my camcorder
simon
also have a look at 802.11e which I think might be addressing QoS in the hidden node problem as well.
simon
You could double your bandwidth at the HillsHub immediately by installing another waveguide, polarized perpendicular to the current one, and on a different non-interfering channel. In australia there's 3 non-interfering channels.
You acknowledge on your page that you are introducing greater latency. Latency is another bugbear of the 802.11 QoS crowd, because it affect voice applications. 802.11 latency also goes way up when the hidden node problem occurs. Again with that situation, increasing bandwidth will solve the problem.
In addition, you said in another post that you collected $150 each --- money that could be spent to install new hubs and/or higher bandwidth hubs.
I'm not dissing your efforts, I think CWNs are great. But there is a broad group of people who think that QoS is needed everywhere, Wi-Fi, in IPv6, etc., and it's bad news.
simon
Hmm.. I thought we were trying to solve the original problem. If you're going to keep piling nodes onto the hub, you're going to hit limits whether you use the 1-5 gigabuck standard or the 10-100 gigabuck proprietary system.
Umm.. yes, you're right, that's exactly my point. The problem is solved by upping the bandwidth, instead of fiddling around with complicated MACs.
I never saw a simple and cheap solution I didn't like. Jacked up bit rates? Bring 'em on. I'll be running at new speeds by the time you get QoS working at the original rate...
simon
I was confused for about 2 seconds. Still, I think OPIE was cool and the name should have been changed out of respect.
simon
Actually CSMA/CA does not include handling of hidden nodes. RTS/CTS was specifically ADDED to 802.11, AFTER CSMA/CA was decided, to handle the hidden node problem.
There is mutual interference between hidden nodes during the RTS/CTS phase.
Score another point for Wi-FUD. That is ONE solution but not the ONLY solution. You could of course, also reduce contention for the shared medium by installing multiple hub radios with sector antennas and save a lot of money. OR, you could upgrade to a faster wireless standard like a or g, and eliminate the contention altogether!
In fact, despite the attempts for people introduce "Quality of Service" measures (which is exactly what fropple or whatever it's called really is), ethernet (10,100,1000MB... and more?), the internet, and dare I say it, Wi-Fi continue to work VERY VERY well based on the model of "best-effort access". Yes, they all degrade rather substantially when put under heavy heavy loads. BUT, the solution is to INCREASE available bandwidth, which leads to new possibilities and innovations and solves the old medium access contention problem at the same time.
simon
First, what the heck is the hidden node problem anyway? It's highly misunderstood. The hidden node problem is when you have a point to multipoint topology in your 802.11 network, aka, a "star" topology. There is one central hub that is connected to the internet, and many nodes that talk to the hub. Now this is all fine and dandy indoors, because indoors usually all of the nodes can hear not just the hub but also each other as well. So they are effectively sharing a single bus, and they can listen to find out if anyone else is using the bus before they talk (classic CSMA situation right?)
Problem is outdoors. Outdoors, you're using long-distance antennas on each of the nodes and an omni on the hub. Now the nodes are mutually deaf, because all they can "see" is the hub, they are too far away from each other to "hear" each other. Thus, they hidden from each other. Now, they cannot perform the Carrier Sense part, because when they listen on the bus, they will not be able to hear if another node is in send mode, sending data to the hub. They will not hear that, and they will decide to broadcast, and the hub will get spammed with two signals at the same time. That's the hidden node problem.
Well there's already a partial solution to the hidden node problem built into 802.11. It's the RTS/CTS system. RTS is Request to Send. Before any node starts talking, it sends a query to the hub, asking if it's all clear. The hub ACKs with a CTS (Clear to Send) response. ALL of the nodes can hear the CTS, so they all delay their own transmissions for a little while.
Of course, you can still have undetectable collisions during the RTS/CTS period! But that's OK, because USUALLY the bandwidth that the hub is CAPABLE of handling FAR exceeds the bandwidth that the nodes NEED. In fact, if you are experiencing the hidden node problem, you can just use TCP throttling to reduce the problem substantially.
We know that the hidden node problem is directly proportional to the percentage of the bandwidth being used. At this point we must say, quite frankly, that the BEST solution is to INCREASE the bandwidth available! Thus, not only do you REDUCE congestion but you also INCREASE speed.
Token ring totally pisses me off. Sure, it's a great idea. You put everyone in a circle and you give one of them a "token". Only the dude with the token is allowed to talk. When they're done talking, they pass the token to the next person, and so on, around the circle, until it comes back and you start again. Great idea in theory.
The problem is there's so many failure cases. What if one node hogs the token? What if a node drops the token? How do you recover from that? What if just one section of the circle dies? When a new node comes online, how do you add it to the token ring? There's a ton of central control required, and that means (a) complexity and (b) overhead and we know that both of those are BAD news.
All that is R&D effort that's totally wasted because all you're doing is making the current system work, that energy could instead be spent on installing a faster model that doesn't get congested in the first place.
</rant>
simon
anyone else remember the other OPIE? What ever happened to that?
802.11a/g are at 54 Mbps, who knows what the next jump will be.
simon
Are you kidding? 22ms is great for voice chat. Think about it ... You're talking about 1/50th of a second here. You really can't tell, trust me.
... there's lots of work in this area.
:-)
The main culprit in VoIP latency is really jitter. That's basically packets that arrive out of order or don't get there and need to be resent. If you've got a lot of jitter it drives up the latency to compensate (the codec needs time to reassemble them in the right order). It's better often just to drop missed packets
Jitter is usually caused by congestion. So, as long as you aren't saturating the link, you should be fine with 22ms
simon
When you're living on a dollar a day, copper is a VERY valuable substance. It's pretty trivial to extract and melt down the copper, once that's done you can't tell if it's stolen or brand new. Easy to launder it back into the normal economy.
South Africa is running a lot of fibre now because, unlike copper, it has no resale value.
simon
I was just reading about telecomm in Africa. Somalia and DRC are both doing GREAT in terms of telephone and internet access. The call prices are far cheaper there, there's more competition, and the business is healthier. Both countries are TOTAL DISASTER AREAS otherwise.
So what's up with that? Turns out that the traditional telephone company model that worked so well for 50 years is now crap. A single state-owned telco simply can't keep up any more. Most African countries kept the state telcos as monopolies even if they did sell them off (so they're private monopolies now) and where there's a monopoly in telephone there's bad service, overprices calls, and an underground market in (usually VSAT-based) IP telephony at cut-rate prices.
simon
Drinking water? How about food from your crops. If you can't talk to an Agricultural expert who can advise you on what to do about the weather, the latest seeds you're getting, the changes in the environment, you might not be eating this winter.
If your water was bad but you can't talk to a doctor about what your symtoms mean, you might treat it with the wrong medicine.
If your kids can't learn because the good teachers in the city don't want to travel over bumpy, muddy, washed out roads, they won't be able to lift themselves up by the bootstraps.
simon
Why do the people of Slashdot ask dumb questions without reading the article?
Since you're probably long gone I'll summarize for you:
0. In rural India, it's often really hard to get to places due to very poor roads, that get washed out in the rain, and the population is very broadly distributed on farms.
1. A teacher in the city can educate children in a rural area. (viz., telecommuting)
2. Doctors can run virtual clinics for villagers to give them medical advice.
3. Scientists can have meetings with local farmers to give them crop advice.
All of these things are IN DEMAND by the people who had a chance to try them out.
simon