I live in a suburb of Philadelphia, PA and comcast tried to do this to me. They did send me a notice though. I replaced their router with a third party wifi router and cable modem. I didn't trust that they would keep their traffic separate from my traffic and I didn't see how someone hanging off of my router wouldn't degrade my service.
Winamp was the first player that could handle massive playlists. I could drag a network folder with over 80 GB of music and it would populate the playlist in seconds. I could then randomize and walk through that list without repeats for days. It also played skipless so that live albums didn't have annoying breaks. New players today still can't do that. Sigh. Their android app is pretty good too. I guess I will jump to amazon now. Their cloud playing is great.
We use openwrt as a base OS. It works pretty well. It has a lot of packages and many single board computer vendors support it. It is pretty hackable and has lots of embedded patches that would never make it into mainline linux but you really need on embedded platforms.
Graphing calculators are an amazingly powerful way to understand functions visually. The ability to instantly draw functions at various scales and trace along them can really help visual learners understand the math.
I wish there was more discussion on the interconnect and routing challenge of these systems. I used to work on an InfiniBand SubnetManager. Exascale will require more complex topologies and more complex routing. Does anyone think today's systems are up to the task?
You can have excel load dll functions. I wrote financial add-ins using this technique with all the real code in c++ with c wrapper exports. The vba was just a bit of glue code.
My thought is what if a LAN client, C, is sending UDP traffic through the AP to A. As long it blasts, B can barely speak. It would be interesting if they were dynamically altering the multi-rate retry algorithm to decrease retries as the queue filled and to even turn on ack requests when the queue was all the way filled. That can help at the cost of reliability. Send it and forget it. I wonder if they experimented with traditional router methods of dealing with queuing issues. Things like Random early drop may help as well.
While the AP is sending faster and more often, clients will suffer. If the AP is blasting to client A, client B will struggle to upload. This may cause client B to disconnect or reassociate. It isn't clear how they prevent starvation at the client transmit side.
As their txqueue fills up they are just shifting packets from the best effort queue to the video queue and then to the voice queue (highest priority). These queues use more air time and have less space between packets. I am curious how it performs under a variety of traffic conditions (upload vs. download vs. mix). It would seem that if uploads and downloads are done at the same time, the downloads will block the uploads. What if the clients do the same thing?
I think enjoying programming is some kind of genetic mutation. No matter who good the software jobs market is, few people get CS degrees or otherwise want to be software engineers or programmers. It isn't quite a mono-culture but programmers and software engineers have so much in common that one can almost forget about how the rest of the world thinks. As you move out to other engineering disciplines, there are still an amazing number of personality traits and interests in common. This is all good for those of us who enjoy programming and would like to be paid well to do it but it is strange to me. I often see IEEE and ACM articles about how to "fix" this issue but I don't think it can be fixed. Most folks would not like what we do even if they were totally capable of doing it.
It sounds like advice to other folks to hire people without a degree in the field so that they will be more loyal to you and less expensive. Without a lot of experience this is true. Folks with a year or two of experience with a degree will earn more than folks with a year or two of experience without a degree. That said, after a few more years it events out.
In the end, you have to judge the individual, what they learned, and how they learned it. I have met idiots who had a degree (even multiple degrees!) and idiots who had no formal education. They come in all shapes and sizes. Anyone who thinks in blanket statements like, "All college graduates in CS are worse than self taught" is proving my point.
I found my programs at West Chester (CS undergrad) and Villanova (master computer engineering) to be very useful and improved my abilities at work. I learned a lot in both and I had been programming since I was 7 or so on my TRS-80 Model III. They also made me more marketable. I feel it was totally worth it.
The military is using meshing products from the company I work at, Rajant, http://www.rajant.com/. They are secure enough for their use. As for reliable, we are used in open pit mining operations with 100s of mobile nodes in vehicles that are like multistory buildings on wheels. These folks loose tons of money if they are down for just the smallest amount of time and they rely on our meshing networks for their fleet control.
I work at http://www.rajant.com/ so I may be a bit biased but our BreadCrumb line will work great for rugged meshing. We support 4.9 GHz radios that are reserved for emergency responders. We are in use by the military and large mining operations that require 24/7/365 networks with 100s of nodes and lives on the line.
They used 10 GigE with a very advanced set of switches that support OpenFlow so that they could get the full bisectional bandwidth. They could have use InfiniBand and probably done much better with FDR adapters capable of 56 gigabit per second. Even "old" IB adapters were faster. Most of the IB switches supported full bisectional bandwidth right out of the box. MS should look at the High Performance Computing world. They need to do handle large amounts of data with low latency.
Microsoft still prints money at an insane rate. They are one of the most profitable public companies in the world year after year and Balmer gets no respect as if he is just coasting on what was there before. It doesn't work that way in tech. You can't coast. Vista was a problem but Windows 7 is a massive success. Windows phone struggles but XBox does well. Windows Server and Office are still cash cows. They are moving up in the virtualization market. People want growth levels out of MS that are just not possible given their size and dominance.
They use sprint's network and are $19/month. You can't get much better than that. Even though the phone costs about $200, you will make it back pretty quickly compared to other plans.
I know about this...I worked on the SilverStorm's Fabric Manager while I was there. I remember going into the VT System-X room and seeing piles of bad cables from earlier setup. If I remember correctly, the very first network had more switch ASICs than hosts...both were around 2000 or so. I think the first switches used 8-port ASICs internally. We made massive improvements to our fabric scan time and reaction time to moving cables, nodes going down, etc. This was a good thing because the non-silverstorm IB switches that were there were at the start were having a failures all the time. I believe System-X eventually moved to SilverStorm IB switches (those 288s and 24 port switches). That 288 was fun to work on. Moving to 24-port ASIC based switches really cuts down on fabric scan and setup time.
They claim they will use 56 gigabit InfiniBand. Has anyone tested Mellanox's FDR adapters and switches? From what I understand, that is 14 gigabit over 4x cabling. I remember all the problems just getting 10 gigabit to work over 4x 2.5 gigabit copper. I imagine this must use fiber to get any distance from the server to the switch.
Their asic seems to support only 36 ports. Building a 2000 node network with 36 port switches will take a lot of interconnected switches. I wonder what topology they are going to use. Is anyone building bigger switches based on many interconnected 36-port asics?
It seems the first article in the main post talks about STEM but doesn't provide any real evidence but may be talking about an article noting the brain drain of the finance world and that the percentage of MIT grads going into finance increased. It was not the majority. This isn't a bad thing. I am a software engineer with a BS in computer science and an MS in computer engineering. I worked on financial software, device drivers, internet advertising software, remote control car embedded software, and wireless meshing software. STEM can take you into all sorts of industries. I don't know why this is a bad thing and I don't think that was what the President was saying.
The author says, "First, American culture has always realized this 'stuff' is important." I find that hard to believe. When I was in school, there were almost no computer science majors. My graduation had 3 CS majors walk with me with over 10,000 students enrolled at the university. Other STEM majors did a bit better but the reality is that our society looks down on STEM folks. It is considered weird and odd. Hollywood uses this stereotype often because the public believes it. We are geeks, nerds, dorks, etc. STEM really does need better PR since keeping the world running doesn't seem to matter much anymore.
The second article attacks pure science jobs. Most folks that major in STEM probably do not go on to pure research jobs. Why is this a bad thing? Many folks become engineers and use the research to create other things. They compare school teachers to scientists even though many are both. Many "pure" researches are college professors. "The women I know who are university professors, by and large, are unmarried and childless. By the time they get tenure, they are on the verge of infertility. " My wife is a university professor and we have two kids thank you. I know several other professional female mathematicians who married and had kids. It seems they these folks get married at the same rate as most other folks and have kids at about the same rate too. Also, the author ignores that the PhD can go into public school teaching and will be paid extra for having the degree. They can leave college and go into the private sector. Some do both. My wife programmed for a while and then came back to teaching because she liked teaching a lot more.
"men tend to lack perspective and are unable to step back and ask the question 'is this peer group worth impressing?' " That is an incredibly sexist statement. Does the author have any proof that women do not do the same? As far as I can tell the sentence should be changed to "people sometimes lack perspective..."
"When Albert goes to graduate school to get his PhD, his choice will have the same logical foundation as John Hinckley's attempt to impress Jodie Foster by shooting Ronald Reagan. " The author compares getting a PhD to being a stalker. This is why STEM needs better PR! Americans see most PhDs as potential stalkers who are just trying to impress the other potential stalkers. Maybe someone gets a PhD because they are actually really interested in the field and really want to study it for its own sake. Maybe someone cares about something other than money. Maybe there is more to life satisfaction than just making more money. Do you want a job that pays 20% more that you will hate or a job that you will love? Perhaps the PhD candidate is actually smarter enough to do what he/she loves.
"What about women? Don't they want to impress their peers? Yes, but they are more discriminating about choosin
I wonder when a GPU will be able to directly access a network of some sort. Right now, you would need glue code on the CPU to link multiple GPUs in different systems together. I imagine that some HPC applications would run quite well with 100 GPUs spread over 25-50 machines with a QDR InfiniBand link between them.
OpenOffice is as bad as word for professional documents and placement of graphics. For my masters thesis, I am using latex and gnuplot. Nothing else that is free seems to get close to getting things correct.
The halfing effect will certainly occur if you only use single radio systems. If you use multiple radio systems that run on different frequency ranges, you can do much better. A good meshing algorithm will avoid the halfing effect by properly using the alternate radios available. If the OLPC had multiple radios, it would do much better as a meshing node.
There are some differences between a many hop city mesh and what I would call a dense mesh. City meshes usually are trying to cover as much space with as little equipment in order to obtain good enough performance. In my idea of a dense mesh each node can see many if not nearly all of the other nodes. The biggest problem becomes route selection when you have lots of very close and similar routes. This can be solved with static configurations but that fails when the mesh nodes themselves are mobile. For that you need a good dynamic route selection algorithm. This kind of dense meshes can occur with mesh nodes in vehicles that are moving around each other.
I wish the OLPC was truely open so that we could understand the route selection and 802.11 rate selection algorithms used. These two algorithms can be a significant effect on mesh performance.
It's really pretty easy to cut power consumption if you're willing to drastically cut performance as well. If you look at performance per watt, the SSD looks pretty good. The SSD article noted above claims, "the 64 GB unit can read 64 MB/S, write 45 MB/s" while the traditional harddrive noted in the post claims, "1138 Mb/s max. media data rate" or 142 MB/s. By the way, I highly doubt it can sustain that but lets just say it can.
If we compare reads vs. reads, we get 64 MB/s in 0.5 watts vs. 142 MB/s in 6.4 watts or: SSD=128MB/s/watt vs. traditional harddrive=22MB/s/watt
"Through a 40-percent power reduction, Hitachi GST has delivered unmatched idle power utilization of 3.6 watts on the 250GB capacity model and 4.8 watts on models with capacities of 320GB or greater. Similarly, the P7K500 has reduced its active power requirements to 6.4 watts and 8.2 watts for its one- and two-disk models, respectively. By utilizing roughly half the 7 watts of idle power typically allocated for hard drives..."
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I live in a suburb of Philadelphia, PA and comcast tried to do this to me. They did send me a notice though. I replaced their router with a third party wifi router and cable modem. I didn't trust that they would keep their traffic separate from my traffic and I didn't see how someone hanging off of my router wouldn't degrade my service.
Winamp was the first player that could handle massive playlists. I could drag a network folder with over 80 GB of music and it would populate the playlist in seconds. I could then randomize and walk through that list without repeats for days. It also played skipless so that live albums didn't have annoying breaks. New players today still can't do that. Sigh. Their android app is pretty good too. I guess I will jump to amazon now. Their cloud playing is great.
We use openwrt as a base OS. It works pretty well. It has a lot of packages and many single board computer vendors support it. It is pretty hackable and has lots of embedded patches that would never make it into mainline linux but you really need on embedded platforms.
Graphing calculators are an amazingly powerful way to understand functions visually. The ability to instantly draw functions at various scales and trace along them can really help visual learners understand the math.
I wish there was more discussion on the interconnect and routing challenge of these systems. I used to work on an InfiniBand SubnetManager. Exascale will require more complex topologies and more complex routing. Does anyone think today's systems are up to the task?
VBA within excel does not consider 1900 a leap year...getting the two to work together is fun.
You can have excel load dll functions. I wrote financial add-ins using this technique with all the real code in c++ with c wrapper exports. The vba was just a bit of glue code.
My thought is what if a LAN client, C, is sending UDP traffic through the AP to A. As long it blasts, B can barely speak. It would be interesting if they were dynamically altering the multi-rate retry algorithm to decrease retries as the queue filled and to even turn on ack requests when the queue was all the way filled. That can help at the cost of reliability. Send it and forget it.
I wonder if they experimented with traditional router methods of dealing with queuing issues. Things like Random early drop may help as well.
While the AP is sending faster and more often, clients will suffer. If the AP is blasting to client A, client B will struggle to upload. This may cause client B to disconnect or reassociate. It isn't clear how they prevent starvation at the client transmit side.
As their txqueue fills up they are just shifting packets from the best effort queue to the video queue and then to the voice queue (highest priority). These queues use more air time and have less space between packets. I am curious how it performs under a variety of traffic conditions (upload vs. download vs. mix). It would seem that if uploads and downloads are done at the same time, the downloads will block the uploads. What if the clients do the same thing?
I think enjoying programming is some kind of genetic mutation. No matter who good the software jobs market is, few people get CS degrees or otherwise want to be software engineers or programmers. It isn't quite a mono-culture but programmers and software engineers have so much in common that one can almost forget about how the rest of the world thinks. As you move out to other engineering disciplines, there are still an amazing number of personality traits and interests in common.
This is all good for those of us who enjoy programming and would like to be paid well to do it but it is strange to me. I often see IEEE and ACM articles about how to "fix" this issue but I don't think it can be fixed. Most folks would not like what we do even if they were totally capable of doing it.
It sounds like advice to other folks to hire people without a degree in the field so that they will be more loyal to you and less expensive. Without a lot of experience this is true. Folks with a year or two of experience with a degree will earn more than folks with a year or two of experience without a degree. That said, after a few more years it events out.
In the end, you have to judge the individual, what they learned, and how they learned it. I have met idiots who had a degree (even multiple degrees!) and idiots who had no formal education. They come in all shapes and sizes. Anyone who thinks in blanket statements like, "All college graduates in CS are worse than self taught" is proving my point.
I found my programs at West Chester (CS undergrad) and Villanova (master computer engineering) to be very useful and improved my abilities at work. I learned a lot in both and I had been programming since I was 7 or so on my TRS-80 Model III. They also made me more marketable. I feel it was totally worth it.
The military is using meshing products from the company I work at, Rajant, http://www.rajant.com/. They are secure enough for their use. As for reliable, we are used in open pit mining operations with 100s of mobile nodes in vehicles that are like multistory buildings on wheels. These folks loose tons of money if they are down for just the smallest amount of time and they rely on our meshing networks for their fleet control.
I work at http://www.rajant.com/ so I may be a bit biased but our BreadCrumb line will work great for rugged meshing. We support 4.9 GHz radios that are reserved for emergency responders. We are in use by the military and large mining operations that require 24/7/365 networks with 100s of nodes and lives on the line.
They used 10 GigE with a very advanced set of switches that support OpenFlow so that they could get the full bisectional bandwidth. They could have use InfiniBand and probably done much better with FDR adapters capable of 56 gigabit per second. Even "old" IB adapters were faster. Most of the IB switches supported full bisectional bandwidth right out of the box. MS should look at the High Performance Computing world. They need to do handle large amounts of data with low latency.
http://ospreyflyer.blogspot.com/p/microsoft-financial-performance.html
Microsoft still prints money at an insane rate. They are one of the most profitable public companies in the world year after year and Balmer gets no respect as if he is just coasting on what was there before. It doesn't work that way in tech. You can't coast. Vista was a problem but Windows 7 is a massive success. Windows phone struggles but XBox does well. Windows Server and Office are still cash cows. They are moving up in the virtualization market. People want growth levels out of MS that are just not possible given their size and dominance.
http://money.cnn.com/magazines/fortune/fortune500/2012/performers/companies/profits/
#4 just below Apple and they did it with much less revenue.
http://money.cnn.com/magazines/fortune/fortune500/2012/full_list/
It used to be that being massive profitiable and having better margins meant something.
They use sprint's network and are $19/month. You can't get much better than that. Even though the phone costs about $200, you will make it back pretty quickly compared to other plans.
I know about this...I worked on the SilverStorm's Fabric Manager while I was there. I remember going into the VT System-X room and seeing piles of bad cables from earlier setup. If I remember correctly, the very first network had more switch ASICs than hosts...both were around 2000 or so. I think the first switches used 8-port ASICs internally. We made massive improvements to our fabric scan time and reaction time to moving cables, nodes going down, etc. This was a good thing because the non-silverstorm IB switches that were there were at the start were having a failures all the time. I believe System-X eventually moved to SilverStorm IB switches (those 288s and 24 port switches). That 288 was fun to work on. Moving to 24-port ASIC based switches really cuts down on fabric scan and setup time.
They claim they will use 56 gigabit InfiniBand. Has anyone tested Mellanox's FDR adapters and switches? From what I understand, that is 14 gigabit over 4x cabling. I remember all the problems just getting 10 gigabit to work over 4x 2.5 gigabit copper. I imagine this must use fiber to get any distance from the server to the switch.
Their asic seems to support only 36 ports. Building a 2000 node network with 36 port switches will take a lot of interconnected switches. I wonder what topology they are going to use. Is anyone building bigger switches based on many interconnected 36-port asics?
According to this article: http://www.huffingtonpost.com/2011/04/11/top-jobs-for-grads-nace-2_n_847505.html engineering jobs are doing quite well. This http://www.businessweek.com/technology/content/nov2008/tc20081113_488542.htm seems to suggest it might even be sexy!
It seems the first article in the main post talks about STEM but doesn't provide any real evidence but may be talking about an article noting the brain drain of the finance world and that the percentage of MIT grads going into finance increased. It was not the majority. This isn't a bad thing. I am a software engineer with a BS in computer science and an MS in computer engineering. I worked on financial software, device drivers, internet advertising software, remote control car embedded software, and wireless meshing software. STEM can take you into all sorts of industries. I don't know why this is a bad thing and I don't think that was what the President was saying.
The author says, "First, American culture has always realized this 'stuff' is important." I find that hard to believe. When I was in school, there were almost no computer science majors. My graduation had 3 CS majors walk with me with over 10,000 students enrolled at the university. Other STEM majors did a bit better but the reality is that our society looks down on STEM folks. It is considered weird and odd. Hollywood uses this stereotype often because the public believes it. We are geeks, nerds, dorks, etc. STEM really does need better PR since keeping the world running doesn't seem to matter much anymore.
The second article attacks pure science jobs. Most folks that major in STEM probably do not go on to pure research jobs. Why is this a bad thing? Many folks become engineers and use the research to create other things. They compare school teachers to scientists even though many are both. Many "pure" researches are college professors. "The women I know who are university professors, by and large, are unmarried and childless. By the time they get tenure, they are on the verge of infertility. " My wife is a university professor and we have two kids thank you. I know several other professional female mathematicians who married and had kids. It seems they these folks get married at the same rate as most other folks and have kids at about the same rate too. Also, the author ignores that the PhD can go into public school teaching and will be paid extra for having the degree. They can leave college and go into the private sector. Some do both. My wife programmed for a while and then came back to teaching because she liked teaching a lot more.
"men tend to lack perspective and are unable to step back and ask the question 'is this peer group worth impressing?' " That is an incredibly sexist statement. Does the author have any proof that women do not do the same? As far as I can tell the sentence should be changed to "people sometimes lack perspective..."
"When Albert goes to graduate school to get his PhD, his choice will have the same logical foundation as John Hinckley's attempt to impress Jodie Foster by shooting Ronald Reagan. " The author compares getting a PhD to being a stalker. This is why STEM needs better PR! Americans see most PhDs as potential stalkers who are just trying to impress the other potential stalkers. Maybe someone gets a PhD because they are actually really interested in the field and really want to study it for its own sake. Maybe someone cares about something other than money. Maybe there is more to life satisfaction than just making more money. Do you want a job that pays 20% more that you will hate or a job that you will love? Perhaps the PhD candidate is actually smarter enough to do what he/she loves.
"What about women? Don't they want to impress their peers? Yes, but they are more discriminating about choosin
I wonder when a GPU will be able to directly access a network of some sort. Right now, you would need glue code on the CPU to link multiple GPUs in different systems together. I imagine that some HPC applications would run quite well with 100 GPUs spread over 25-50 machines with a QDR InfiniBand link between them.
OpenOffice is as bad as word for professional documents and placement of graphics.
For my masters thesis, I am using latex and gnuplot. Nothing else that is free seems to get close to getting things correct.
The halfing effect will certainly occur if you only use single radio systems. If you use multiple radio systems that run on different frequency ranges, you can do much better. A good meshing algorithm will avoid the halfing effect by properly using the alternate radios available. If the OLPC had multiple radios, it would do much better as a meshing node.
There are some differences between a many hop city mesh and what I would call a dense mesh. City meshes usually are trying to cover as much space with as little equipment in order to obtain good enough performance. In my idea of a dense mesh each node can see many if not nearly all of the other nodes. The biggest problem becomes route selection when you have lots of very close and similar routes. This can be solved with static configurations but that fails when the mesh nodes themselves are mobile. For that you need a good dynamic route selection algorithm. This kind of dense meshes can occur with mesh nodes in vehicles that are moving around each other.
I wish the OLPC was truely open so that we could understand the route selection and 802.11 rate selection algorithms used. These two algorithms can be a significant effect on mesh performance.
The SSD article noted above claims, "the 64 GB unit can read 64 MB/S, write 45 MB/s"
while the traditional harddrive noted in the post claims, "1138 Mb/s max. media data rate" or 142 MB/s. By the way, I highly doubt it can sustain that but lets just say it can.
If we compare reads vs. reads, we get 64 MB/s in 0.5 watts vs. 142 MB/s in 6.4 watts or:
SSD=128MB/s/watt vs. traditional harddrive=22MB/s/watt
My bet is that solid state drives do much better. Moving parts consume a lot of power.
http://news.digitaltrends.com/news/story/12556/samsung_announces_64_gb_solid_state_drive
"...consumes just half a Watt when operating (one tenth of a Watt when idle)"
vs. from the article:
"Through a 40-percent power reduction, Hitachi GST has delivered unmatched idle power utilization of 3.6 watts on the 250GB capacity model and 4.8 watts on models with capacities of 320GB or greater. Similarly, the P7K500 has reduced its active power requirements to 6.4 watts and 8.2 watts for its one- and two-disk models, respectively. By utilizing roughly half the 7 watts of idle power typically allocated for hard drives..."