I would seriously start the design process with the storage system. Email is mostly just "storage" that is accessed by many different servers all at once. It needs to be fast, fault tolerent and easy to backup while in use for this a "point in time snapshot" feature is good. You may want to talk to Sun about thier "ZFS" filesystem on Solaris 10. If not read up onwhat it does and then get something else like it.
Once you have bomb proof storage running on a cluster of servers, raid, hot spares a transactinal file systam and all that than you add smtp, imap, pop webmail servers. Use lots of MX record, round robin DNS or whatever to load balance. If the storage don't work the system will not work, get that right first
Lots more detils but "this is/." and peole here think for only 2 seconds (if that) before they type an answer
BTW 99.9 is setting the sights a bit low that would alow about 8 hours of downtimeer year. Shoot for another "9".
"I think in the end it would inevitably come to a fight."
Look at the population density of Europe at that time. It was _Very_ low. Low enough that the two groups would not bump intoeachother very often. Just remember how long it takes to walk 5 miles when there are no roads. Rather then direct confontation it likely went more like "We can't live here anymore because there is to little food, let's move. So they move. Over time there is no place let to move to. This is they way species go extinct today, someone else moves onto thier land so they move onto poorer land and the cyle continues.
It would have been nearly impossable for modern humans to have killed each Neanderthal simply because of the low chance of meeting one given the low population density. Most likely we just slowly took over thier land and eat their food.
"Other than Sun's high licensing costs I'm at a loss on why Solaris would be so much higher."
High Cost???? Solaris is available for free. It is Open Source. Even if yo do buy a support contract the cost is low,
Yes Sun does make some expensive hardware but machines with 64 processors are expensive no matter which OS you use. Down at the mid range, say a computer with dual Opteron CPUs and 2 or 4 GB RAM Sun has competitive prices.
Sun solaris on AMD and Linux on Intel or very close and the casual user likey could not tell one from the other. I use both dialy.
You are Exactly right. I doubt there is a "grammar module" in the brain. Note that we can learn sign language, music and to read. I think these other abilities are due to a general purpose ability to recognise paterns. Language itself must have evolved from something that was not language. Lkey from some general ability to recognise patterns and make abstractions
"I fail to see why formations of smaller satellites should be a new developmenT"
The word "formation" is what's new. Without explaining the physics just take my word for it. "formations" is hard. Also "small" is hard too the size of an antenna for example is determined by the wavelnght of the signal and the desired beamwidth. YOu can't just make it smaller. A "formation" is one way to address this. It is really a large sat but with empty space between the parts. Satalites need electric power even when they are in darkness (half the time) your cell phone (say), needs a certain level of power or it can't "hear" the signal. Batteries take space Anyways the bottom line is that you are NOT going to be doing direct broadcast TV from a milkcarton sized satilite. BUT the exciting part is that if you can build a cheap enough satilite then you can do taskes that where not cost efective before. It's lke when computers cost a millin dollors each, you choose the tasks you gave them very carfully but now that they are $300 each children can use them to play games. We will find new uses for space when space gets cheap. and with sats this small it's cheap, within a university's budget. In the space bussines it is almost exactly true that cost == weight Again this is exiting because of all the new applications that become economically possable and because any of us could be the person to think of the "next new thing"
"VM sandbox that would then allow the a program to run to see what it would do,"
Not a bad idea except if the virus is programed to do nothing for period of time or until some event happens like the 11,347th keystoke and then get on with "whatever". How could the VM know what would trigger the action?
There is a simple method. Design an Operating system that knows about "usrs" and only run anonymous code as the user "anonymous" who is allowed to access almost nothing.
OSes that enforce various types of access controls don't have this problem.
Back when I learned it was COBOL, FORTRAN and IBM System 360 Assembly. Technology has changed since the 1970's but ther basic concepts have not. I would suggest that you teach the basic concepts and explain to the students that you will use a couple programiing languages to ilistrait the concepts. Students should walk away from the class knowing that learning the syntax of some programming laanguage is NOT llearning to program. This is actually a hrad concept for beginners. But once they learn the designing a program and writting the code are two seporate things they will be better off. So I'd suggest you need a small handfull of languages and show how they differ andhow each is usfull for differnt things
Not much to offer without knowing more about how the system is designed. If the DBMS is replicated 12 times I suspect some kind of _serious_ design problem and the best fix would be to re-think the aplication.
The best advice is to tell the person to get onto some DBMS forums and talk about his aplication and how best to design it. Notice I say "DBMS forums" not MySQL forums. Need to step way back and look at the bigger picture and not ask about low-level mysql related nuts and bolt issues.
The best tool for "painting yourself in a corner" really quick is a DBMS in the hands of someone with not training in database design.
Performance is NOT and issue I've clocked thousands of querries per second using standard PC hardware and MySQL or PostgreSQL
"If they were just trying to locate 911 callers, this could easily be done with a caller-enabled location system."
Yes, There is even an example of this type of thing in common usage. It is the "DSC Enabled Marine Radio" This is now required equipment on ships and some boats. Basically there is a big red botton, with a cover that you press in an emergency. The radio then makes a digital call that includes the location (from a connected GPS) and the ID of the radio's registered owner. They sell for "way cheap" as low as about $160 and that is for a 25W (not milliwatt) transmitter.
For this application the phone would simply ASK the nearest WiFi gateway "where am I" no GPS needed. It would then forward that info
One other litle fact. GPS does NOT work inside many buildings. If you built GPS into a phone it would not work much of the time. GPS needs a clear view iof the sky, sometimes even trees can obstruct the signal.
My suggestion: A little red "emergency" button that can auto dial 911 and forward location info. Cost maybe a buck?
How is it done? First you have to realie the "NASA" is not just one person. It's a huge agency and theyhire contractrs too. SO there is not one program on a PC some place. These are hundreds. THe technique used depends of the purpose. So what are you trying to do? Do a "what if" calculation while you are still designing the system and trying to do a trade study of weight, fuel, time and so on, or are you trying to compute the burn time for a mid course correction? For the best accuracy the method is NOT closed form. You simulate little slices of "delta t" using (typically for earth orbit missions) Earth,moon, sun,jupiter. I suppose if you were going to mars you'd add mars too. Then you chosewhat is Delta t based on allowed error.
"Ingres was just open-sourced by Computer Associates this summer". Wel yes and no....
Ingres was the very first ever relational database. It pre-dated the wide spread use of SQL. It was released under a BSD style license and was Open Source before the term "open Source" was in wide use. Later Ingres was further developed comercially and sold as a product and the old Open Source version becames known as "University Ingres". It is the later comercial version that is now open sourceed.
PostgreSQL (aka Postgres) comes from the same university develoers as Ingres. It was hier next DBMS hencethe name post-gress for after-ingres Postgres has linage dating back to the first first RDBMS. Postgres too was started before SQL wa universal but was converted over to accept SQL in 1995 and then later renamed "PostgreSQL" (with the "QL" being silent)
Bottom line, Ingres was the grandfather of open source DMBSes and has severa importent children.
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I would seriously start the design process with the storage system. Email is mostly just "storage" that is accessed by many different servers all at once. It needs to be fast, fault tolerent and easy to backup while in use for this a "point in time snapshot" feature is good. You may want to talk to Sun about thier "ZFS" filesystem on Solaris 10. If not read up onwhat
/." and peole here think for only 2 seconds (if that) before they type an answer
it does and then get something else like it.
Once you have bomb proof storage running on a cluster of servers, raid, hot spares a transactinal file systam and all that than you
add smtp, imap, pop webmail servers. Use lots of MX record, round robin DNS or whatever to load balance. If the storage don't work the system
will not work, get that right first
Lots more detils but "this is
BTW 99.9 is setting the sights a bit low that would alow about 8 hours of downtimeer year. Shoot for another "9".
"I think in the end it would inevitably come to a fight." Look at the population density of Europe at that time. It was _Very_ low. Low enough that the two groups would not bump intoeachother very often. Just remember how long it takes to walk 5 miles when there are no roads. Rather then direct confontation it likely went more like "We can't live here anymore because there is to little food, let's move. So they move. Over time there is no place let to move to. This is they way species go extinct today, someone else moves onto thier land so they move onto poorer land and the cyle continues. It would have been nearly impossable for modern humans to have killed each Neanderthal simply because of the low chance of meeting one given the low population density. Most likely we just slowly took over thier land and eat their food.
"Other than Sun's high licensing costs I'm at a loss on why Solaris would be so much higher." High Cost???? Solaris is available for free. It is Open Source. Even if yo do buy a support contract the cost is low, Yes Sun does make some expensive hardware but machines with 64 processors are expensive no matter which OS you use. Down at the mid range, say a computer with dual Opteron CPUs and 2 or 4 GB RAM Sun has competitive prices. Sun solaris on AMD and Linux on Intel or very close and the casual user likey could not tell one from the other. I use both dialy.
You are Exactly right. I doubt there is a "grammar module" in the brain. Note that we can learn sign language, music and to read. I think these other abilities are due to a general purpose ability to recognise paterns. Language itself must have evolved from something that was not language. Lkey from some general ability to recognise patterns and make abstractions
"I fail to see why formations of smaller satellites should be a new developmenT" The word "formation" is what's new. Without explaining the physics just take my word for it. "formations" is hard. Also "small" is hard too the size of an antenna for example is determined by the wavelnght of the signal and the desired beamwidth. YOu can't just make it smaller. A "formation" is one way to address this. It is really a large sat but with empty space between the parts. Satalites need electric power even when they are in darkness (half the time) your cell phone (say), needs a certain level of power or it can't "hear" the signal. Batteries take space Anyways the bottom line is that you are NOT going to be doing direct broadcast TV from a milkcarton sized satilite. BUT the exciting part is that if you can build a cheap enough satilite then you can do taskes that where not cost efective before. It's lke when computers cost a millin dollors each, you choose the tasks you gave them very carfully but now that they are $300 each children can use them to play games. We will find new uses for space when space gets cheap. and with sats this small it's cheap, within a university's budget. In the space bussines it is almost exactly true that cost == weight Again this is exiting because of all the new applications that become economically possable and because any of us could be the person to think of the "next new thing"
"VM sandbox that would then allow the a program to run to see what it would do," Not a bad idea except if the virus is programed to do nothing for period of time or until some event happens like the 11,347th keystoke and then get on with "whatever". How could the VM know what would trigger the action? There is a simple method. Design an Operating system that knows about "usrs" and only run anonymous code as the user "anonymous" who is allowed to access almost nothing. OSes that enforce various types of access controls don't have this problem.
Back when I learned it was COBOL, FORTRAN and IBM System 360 Assembly. Technology has changed since the 1970's but ther basic concepts have not. I would suggest that you teach the basic concepts and explain to the students that you will use a couple programiing languages to ilistrait the concepts. Students should walk away from the class knowing that learning the syntax of some programming laanguage is NOT llearning to program. This is actually a hrad concept for beginners. But once they learn the designing a program and writting the code are two seporate things they will be better off. So I'd suggest you need a small handfull of languages and show how they differ andhow each is usfull for differnt things
Not much to offer without knowing more about how the system is designed. If the DBMS is replicated 12 times I suspect some kind of _serious_ design problem and the best fix would be to re-think the aplication. The best advice is to tell the person to get onto some DBMS forums and talk about his aplication and how best to design it. Notice I say "DBMS forums" not MySQL forums. Need to step way back and look at the bigger picture and not ask about low-level mysql related nuts and bolt issues. The best tool for "painting yourself in a corner" really quick is a DBMS in the hands of someone with not training in database design. Performance is NOT and issue I've clocked thousands of querries per second using standard PC hardware and MySQL or PostgreSQL
"If they were just trying to locate 911 callers, this could easily be done with a caller-enabled location system." Yes, There is even an example of this type of thing in common usage. It is the "DSC Enabled Marine Radio" This is now required equipment on ships and some boats. Basically there is a big red botton, with a cover that you press in an emergency. The radio then makes a digital call that includes the location (from a connected GPS) and the ID of the radio's registered owner. They sell for "way cheap" as low as about $160 and that is for a 25W (not milliwatt) transmitter. For this application the phone would simply ASK the nearest WiFi gateway "where am I" no GPS needed. It would then forward that info One other litle fact. GPS does NOT work inside many buildings. If you built GPS into a phone it would not work much of the time. GPS needs a clear view iof the sky, sometimes even trees can obstruct the signal. My suggestion: A little red "emergency" button that can auto dial 911 and forward location info. Cost maybe a buck?
How is it done? First you have to realie the "NASA" is not just one person. It's a huge agency and theyhire contractrs too. SO there is not one program on a PC some place. These are hundreds. THe technique used depends of the purpose. So what are you trying to do? Do a "what if" calculation while you are still designing the system and trying to do a trade study of weight, fuel, time and so on, or are you trying to compute the burn time for a mid course correction? For the best accuracy the method is NOT closed form. You simulate little slices of "delta t" using (typically for earth orbit missions) Earth,moon, sun,jupiter. I suppose if you were going to mars you'd add mars too. Then you chosewhat is Delta t based on allowed error.
"Ingres was just open-sourced by Computer Associates this summer". Wel yes and no.... Ingres was the very first ever relational database. It pre-dated the wide spread use of SQL. It was released under a BSD style license and was Open Source before the term "open Source" was in wide use. Later Ingres was further developed comercially and sold as a product and the old Open Source version becames known as "University Ingres". It is the later comercial version that is now open sourceed. PostgreSQL (aka Postgres) comes from the same university develoers as Ingres. It was hier next DBMS hencethe name post-gress for after-ingres Postgres has linage dating back to the first first RDBMS. Postgres too was started before SQL wa universal but was converted over to accept SQL in 1995 and then later renamed "PostgreSQL" (with the "QL" being silent) Bottom line, Ingres was the grandfather of open source DMBSes and has severa importent children.