Israel was pretty close to being overwhelmed - it was luck (or talent) that changed the tide in the golan heights, not the nukes they had but didn't use.
> The network will cover 20+ states, and several European and Asian countries and Australia. * Our system allows for "satellites" which are remote monitoring stations allowing you to perform checks against a given node from several remote locations. * Our system works well even in NAT'ed setups where several remote private-network sites report in status info to a central monitoring server * You can even delegate administrative tasks, so that the asian administrators can view only their own systems but may have administrative privileges there, for example
> about 30 servers mixed between linux and windows * In addition to SNMP and various network checks (HTTP/...) we provide an agent which provides detailed system monitoring data for your servers - this agent runs on both Windows and the most common Linux distributions (in addition to NetWare/HP-UX/Solaris/...)
> really decent cheap web based monitoring application to maintain the entire system. * You can get on-line quotes on our site, or send a mail to sales@... they will answer:) * Both configuration and day-to-day monitoring operations is completely web based * We have clever web-based configuration system to make it easy to set up detailed monitoring on large networks
All in all, there's pros and cons to all the systems you mention and (no surprise) to ours as well. No two are really alike. My best advise to you is to take a look around, get some free trials going and see what you like. And talk to the vendors. If they won't help you during the trials, they probably won't either when you face real problems later on.
In spite of this being a blatant plug for the company I work for, I hope the moderators will go lightly on this post since it is completely on topic and specifically answers the question asked. Thank you very much:)
Not for everything. Konq. actually does a decent job of showing directories with loads of images (8+ Mpixel jpegs/tiffs) as thumbnails. Something bash doesn't (yet) do well.
The much cooler feature is, that the *same* file browser component is used in every KDE app - so when you want to burn a CD or whatever, K3B shows you the *same* thumbnail-view of your image catalogue as you used in Konq before when sorting the images. This may sound simple but it is such a basic necessity that it is beyond me why neither windows nor gnome seems to have even thought of it.
No no... The UltraSPARK processor is the KDE version. For reasons unknown, Sun is moving forward with the (Gnome based) JDS, so you'll have more luck in tracking the UltraSPARG.
...when my ISP screwed up their bandwidth limiting.
I have broadband, 2 Mbit/s symmetrical. Apparantly the provider have decided to base their entire network infrastructure on ATI equipment. While this might sound bad at first (after all, what good is broadband if your uplink is dead), I've found that this is not so terrible after all. Since the equipment to the household is all standard fast ethernet, they cap the bandwidth in some (ATI) device somewhere. This is where things get interesting.
I do have connectivity all the time. However, recently my 2 MBit/s bandwidth limiting got screwed up, so I've had between 40 and 50 MBit/s for what amounts to about $23/month.
Ok, first of all; if I could cook an egg in say five minutes using two phone, I could cook it in 10 minutes using one phone. I talk longer than that on the phone sometimes - how would the right side of my brain look if the phone actually emitted enough energy to boil an egg in that time? Right - you would faint after talking just a few seconds (heating the brain is *really* not a good-for-you thing to do). After 10 minutes of talking you wouldn't be able to guess your own name, should you wake up...
So, obviously this is BS.
Now. A big egg, let's say that's about 80 grams of mass, and that the specific heat of the combined egg contents is similar to water (shouldn't be too much of a long shot). So, we have 80 grams of something that has a specific heat close to 4 joules/(gram*kelvin).
To boil that, we need to heat it about 80 kelvin (room temperature around 293 kelvin, water boiling at 373 kelvin). That's 4 [joules/(gram*kelvin)] * 80 [kelvin] = 320 [joules/gram].
We had 80 grams of egg. This gives us 80 [grams] * 320 [joules/gram] = 25600 [joules].
We had five minutes to do this - that's 5*60=300 seconds. A joule being one watt in one second, we get: 25600 [watt*second] / 300 [seconds] = 85 [watts]. So, using 85 watts for five minutes should get an egg from room temperature to the boiling point of water. Approximately.
Each phone would then have to emit around 42 watts (could this be a coincidence? Oh, nevermind..).
Let's say you get around one third of the energy into the egg (I'm really being generous here - the egg would have to cover 1/3 of the output of the antenna and completely absorb the energy) - you would need two phones each with a 126 watt transmitter.
Mobile phones with 100+ watt transmitters? I know there are rural areas in the US of A, but I sincerely doubt that it's common to carry phones that pack that much punch.
Besides, the article talked about 2 watt output phones... Again, BS.
It's like when MS picked "SQL server" for their SQL server product. A: What SQL server are you guys running? B: Oh, we're using SQL server. A: Yes, but *which* SQL server? Oracle? Sybase? B: No, SQL server! A: Yes but.... doh!
Now that everyone else have been selling multi-core processors for some time, Intel chose to brand their new processor geenration, of all things, "Core". A: What multi-core processors are you guys using? B: Oh, we're using multiple Core processors A: Yes, but *which* multi-core processors? B: We're using multiple Core processors! *doh*
You can't heat water up quickly enough with conventional resistance-based electric elements, as it would require huge amount of electricity. Not so with microwaves
A resistance-based heater system has very very close to 100% efficiency. Except for the loss in the wires to the heater element (this loss is negligable and in any case better wires mean even less loss - this is just not a problem), a resistance-based heater converts *all* energy sent to it into heat. No light, no movement, just heat. This is as ideal as it gets. One joule of electrical energy becomes one joule of heat energy. No loss. Really.
So, eh, the microwave heater can do the same job with less "electricity" ?
This must be my favourite personal quest - because it was difficult, because I found a solution, and because that solution beat the crap out of some research groups rather respected solution (in a very sepcific use case though, but still).
The problem is to order rows and columns in a matrix so that a following QR factorization will be most efficient, computationally (the result of the factorization will not change with the ordering, but the amount of computational work changes as zeros and non-zeros are re-ordered by means of reordering rows or columns).
You have a point, and maybe you're right - but don't be so sure.
It would be difficult to pull of a somewhat real-world alike test where a Xeon would beat an Opteron.
Anyone could pull off a synthetic benchmark that would prove Xeon to be the faster CPU of course, but I'm pretty sure you will find it difficult to take off-the-shelf server software and make it run faster on a properly configured Xeon than on a properly configured Opteron.
What you're saying is probably close to true - and a *lot* of ISPs do filter outgoing port 25 traffic.
However, it is beyond me why this is effective. Everyone and their dog will have their e-mail client (for most probably outlook/-express) configured to properly send all outgoing e-mail via. the ISP provided SMTP relay.
If a program uses the standard mail API in windows, those settings will be used and a mail will be transmitted properly through any defined relays. For some reason, the worms choose to implement their own SMTP layer directly atop of the socket layer, rather than saving the work and using the standard API. And *this* alone causes port 25 filtering to be effective.
The first worm that simply utilises the standard mail API will effectively bypass any port 25 blocking.
Maybe they put a GPS receiver and a huge radio transmitter on the sun, so that the sun can relay its location to earth... Oh wait, no, that wouldn't work...
It's a mystery. It's not like it is difficult to determine the approximate direction of the most intensive light source (which should be the only positioning the dish would need).
Let's say the volume of the smallest cylinder that contain the fan would be 1 liter (using round numbers here). With five fan blades, that would mean that the fan could move 5 liters of air per revolution.
That would mean something like 5000 revolutions per second.
Ok, so the radius of the fan is something like 0.1 meter (round numbers remember), giving approximately a peripheral speed of 3000 meters per second.
That's around mach-10.
Somehow I doubt the "Quiet CPU Cooler" sticker on the fan is going to hold true.
Nah, wait, somehow I just doubt a few of the numbers there;)
The cool thing about stable debian is, that it *doesn't* upgrade to the latest version of all the software.
It just installs security updates.
That way, I don't need to worry about database upgrades, configuration file changes, API/protocol changes etc. etc. etc. Everything that ran before, runs afterwards, unchanged.
*that* is cool. If you're running production servers in the real world at least:)
I know he called that one. That doesn't make me feel any better though...
I think I should clarify that;
Debuggers are not illegal as such - they are only illegal to *use* for most purposes, with the notable exception of "research".
So you can argue we're bending the law more than breaking it, by using debuggers for, eh, debugging our own products. Same with disassemblers.
In any case, the law was not intended to outlaw software development entirely, it was only intended to outlaw software development that the MPAA did not endorse.
You know, when laws like this pass, I have this hope deep inside me, that the responsible politicians were bribed. Because, if they were bribed, there would be a rational explanation and a good reason (however immoral), as to how the law could pass.
If we assume that they were not bribed, that would make incompetence the only explanation. And that scares me - to think that someone with that amount of influence and responsibility could be incompetent to such levels. That scares me.
I hope simple greed did it. Unfortunately, I am most likely mistaken.
You see, sw patents are only a problem when you are starting up new business - if you are IBM (or Microsoft to some extent) already, then they are useful.
My point here being, that software patents are only 'stifling' if you intend to start up new business.
And you are only likely to realize this, if you realize that starting up new businesses is important for an economy to grow.
Back in the late '90s our government found out that Denmark should be a country of innovation, a high-tech economy so to speak - we cannot compete with china on industrial production costs anyway. So, in order to "boost" research they shut down the only government super computing center we had, sending researchers elsewhere to go beg for computing power.
To further strenghten our position as a nation of researchers and scientists, we have one of the most expensive but crappiest primary school systems in the western world - which is one thing, but the fact that anyone refuses to do anything about it underlines how important it is to the government to really position our country with a high-tech economy. Or not...
Copyright law was changed last year, to make it illegal to use or develop debuggers and disassemblers. I wrote to the minister in change of that decision letting him know that I and anyone else developing software would be breaking that law. Got some bullshit answer back which didn't address the problem, so now I'm practicing my right to "civil disobedience" every day on the job, along with everyone else in the software business in this country...
800 jobs is money right here right now. "Stifling" is in the eye of the beholder. For a government which is determined to break any initiative or start-up business, either indirectly thru neglect or directly thru law, it seems like it is not such a tough decision to make.
Oh, and add a photo opportunity with Bill and it's a done deal.
Dude, they're not trying to destroy anything in particular.
You can buy a box that will run Red Hat from them if you want - if you don't like Solaris under the CDDL, just go ahead and run Red Hat, or run the good ole binary Solaris.
It's not like they're hurting anyone in any way other than offering a product under a given license. They are not taking anything *away* from others.
If you don't like it, don't use it.
Just like every other product out there, be it GPL'ed, BSD'ed or evil capitalist proprietary.
Ok, a dish is a high-gain antenna. Is it because the antenna magically produces energy from nothing and amplifies the signal? No.
Gain comes at a price.
The only way an antenna can produce gain, is, by limiting the directions in which it is effective.
A longer dipole (vertically mounted) becomes less effective in the vertical range - which means a long dipole that is perfectly vertical will not really transmit a lot of the energy upwards (and will therefore suck for satellite communication - which you don't care about, but which explains why vertically mounted high-gain dipoles are not used for satellite communication:)
A dish becomes even more effective by limiting its effectiveness in all other directions than "straight ahead". The better the dish, the narrower "straight ahead" becomes, and the higher the gain therefore becomes "straight ahead".
But you want signal over a large horizontal area, as I understand it. Yet people suggest dishes...
So, unless you want motorized dishes (either remotely controlled which would be a real pain for the user which would need to carry a remote control and continuously reposition the base station dish towards his location, or automatically homing on thermal activity or whatever - totally undoable on the budget you seem to have) on your base stations, don't consider dish antennas. They will be very efficient in a very limited direction, and ineffective everywhere else.
High gain dipoles might work for you, though.
Please, whatever you do, before endeavoring into alternative antenna configurations, make sure you understand what the implications of a given antenna design are (something a slashdotter or two seem to have momentarily forgotten, judging by the comments in this thread).
Absolutely correct (and his nonsence about common identifications of the "screen" you're working on being outdated, well, guess he never noticed the title bar in his windows...)
Also, take a look at the Orange book - it's from 1985, and close to 100% of what you find in there is as relevant and correct as ever, but unlike the user interface guidelines, the computing industry has not (except for a few notable exceptions) seemed to really converge towards compliance here.
(closest thing you get in a general purpose OS is Trusted Solaris, certified against the LSPP, which corresponds pretty much to the 'B2' profile from Orange book. Nobody ever made a general purpose OS that even approached B3 (let alone A1 and beyond) from Orange book).
With all the "computer security" fluff in the media these days, it's easy to feel disappointed at the "evolution" in the IT world when you read the 20 year old cook-book to how secure systems can be built.
Nobody cared enough. And people pay dearly for that today.
Slashdot Mirror
Hmm, and then again...
Israel was pretty close to being overwhelmed - it was luck (or talent) that changed the tide in the golan heights, not the nukes they had but didn't use.
You could take a look at: http://www.sysorb.com/
:)
:)
> The network will cover 20+ states, and several European and Asian countries and Australia.
* Our system allows for "satellites" which are remote monitoring stations allowing you to perform checks against a given node from several remote locations.
* Our system works well even in NAT'ed setups where several remote private-network sites report in status info to a central monitoring server
* You can even delegate administrative tasks, so that the asian administrators can view only their own systems but may have administrative privileges there, for example
> about 30 servers mixed between linux and windows
* In addition to SNMP and various network checks (HTTP/...) we provide an agent which provides detailed system monitoring data for your servers - this agent runs on both Windows and the most common Linux distributions (in addition to NetWare/HP-UX/Solaris/...)
> really decent cheap web based monitoring application to maintain the entire system.
* You can get on-line quotes on our site, or send a mail to sales@... they will answer
* Both configuration and day-to-day monitoring operations is completely web based
* We have clever web-based configuration system to make it easy to set up detailed monitoring on large networks
All in all, there's pros and cons to all the systems you mention and (no surprise) to ours as well. No two are really alike. My best advise to you is to take a look around, get some free trials going and see what you like. And talk to the vendors. If they won't help you during the trials, they probably won't either when you face real problems later on.
In spite of this being a blatant plug for the company I work for, I hope the moderators will go lightly on this post since it is completely on topic and specifically answers the question asked. Thank you very much
Not for everything.
Konq. actually does a decent job of showing directories with loads of images (8+ Mpixel jpegs/tiffs) as thumbnails. Something bash doesn't (yet) do well.
The much cooler feature is, that the *same* file browser component is used in every KDE app - so when you want to burn a CD or whatever, K3B shows you the *same* thumbnail-view of your image catalogue as you used in Konq before when sorting the images. This may sound simple but it is such a basic necessity that it is beyond me why neither windows nor gnome seems to have even thought of it.
It's the little things in everyday usage...
No no... The UltraSPARK processor is the KDE version. For reasons unknown, Sun is moving forward with the (Gnome based) JDS, so you'll have more luck in tracking the UltraSPARG.
...when my ISP screwed up their bandwidth limiting.
:)
I have broadband, 2 Mbit/s symmetrical. Apparantly the provider have decided to base their entire network infrastructure on ATI equipment. While this might sound bad at first (after all, what good is broadband if your uplink is dead), I've found that this is not so terrible after all. Since the equipment to the household is all standard fast ethernet, they cap the bandwidth in some (ATI) device somewhere. This is where things get interesting.
I do have connectivity all the time. However, recently my 2 MBit/s bandwidth limiting got screwed up, so I've had between 40 and 50 MBit/s for what amounts to about $23/month.
That rocks
Go ATI!
Ok, first of all; if I could cook an egg in say five minutes using two phone, I could cook it in 10 minutes using one phone. I talk longer than that on the phone sometimes - how would the right side of my brain look if the phone actually emitted enough energy to boil an egg in that time? Right - you would faint after talking just a few seconds (heating the brain is *really* not a good-for-you thing to do). After 10 minutes of talking you wouldn't be able to guess your own name, should you wake up...
So, obviously this is BS.
Now. A big egg, let's say that's about 80 grams of mass, and that the specific heat of the combined egg contents is similar to water (shouldn't be too much of a long shot). So, we have 80 grams of something that has a specific heat close to 4 joules/(gram*kelvin).
To boil that, we need to heat it about 80 kelvin (room temperature around 293 kelvin, water boiling at 373 kelvin). That's 4 [joules/(gram*kelvin)] * 80 [kelvin] = 320 [joules/gram].
We had 80 grams of egg. This gives us 80 [grams] * 320 [joules/gram] = 25600 [joules].
We had five minutes to do this - that's 5*60=300 seconds. A joule being one watt in one second, we get: 25600 [watt*second] / 300 [seconds] = 85 [watts]. So, using 85 watts for five minutes should get an egg from room temperature to the boiling point of water. Approximately.
Each phone would then have to emit around 42 watts (could this be a coincidence? Oh, nevermind..).
Let's say you get around one third of the energy into the egg (I'm really being generous here - the egg would have to cover 1/3 of the output of the antenna and completely absorb the energy) - you would need two phones each with a 126 watt transmitter.
Mobile phones with 100+ watt transmitters? I know there are rural areas in the US of A, but I sincerely doubt that it's common to carry phones that pack that much punch.
Besides, the article talked about 2 watt output phones... Again, BS.
Ahhh.... Have a nice day.
Who dreamt up the "Core" brand?
It's like when MS picked "SQL server" for their SQL server product.
A: What SQL server are you guys running?
B: Oh, we're using SQL server.
A: Yes, but *which* SQL server? Oracle? Sybase?
B: No, SQL server!
A: Yes but.... doh!
Now that everyone else have been selling multi-core processors for some time, Intel chose to brand their new processor geenration, of all things, "Core".
A: What multi-core processors are you guys using?
B: Oh, we're using multiple Core processors
A: Yes, but *which* multi-core processors?
B: We're using multiple Core processors!
*doh*
Oh dear oh dear...
You can't heat water up quickly enough with conventional resistance-based electric elements, as it would require huge amount of electricity. Not so with microwaves
A resistance-based heater system has very very close to 100% efficiency. Except for the loss in the wires to the heater element (this loss is negligable and in any case better wires mean even less loss - this is just not a problem), a resistance-based heater converts *all* energy sent to it into heat. No light, no movement, just heat. This is as ideal as it gets. One joule of electrical energy becomes one joule of heat energy. No loss. Really.
So, eh, the microwave heater can do the same job with less "electricity" ?
It has, what, a rod of plutonium inside?
Come on.
It's the width, not the length, that matters ;)
(Look where Intel got with their long pipelines, and see where good fat interconnects and amd64 took AMD)
This must be my favourite personal quest - because it was difficult, because I found a solution, and because that solution beat the crap out of some research groups rather respected solution (in a very sepcific use case though, but still).
:)
The problem is to order rows and columns in a matrix so that a following QR factorization will be most efficient, computationally (the result of the factorization will not change with the ordering, but the amount of computational work changes as zeros and non-zeros are re-ordered by means of reordering rows or columns).
Tiny presentation of the optimization problem.
Page with pretty pictures of the original and re-ordered systems (a solution found by my optimizer).
And of course, you could just go ahead and read the whole deal - uh, did I mention the software is open source?
Exactly.
Which is also why it is so much better to have Intel *not* compete than it is to have AMD provide an Intel box for testing.
You have a point, and maybe you're right - but don't be so sure.
It would be difficult to pull of a somewhat real-world alike test where a Xeon would beat an Opteron.
Anyone could pull off a synthetic benchmark that would prove Xeon to be the faster CPU of course, but I'm pretty sure you will find it difficult to take off-the-shelf server software and make it run faster on a properly configured Xeon than on a properly configured Opteron.
What you're saying is probably close to true - and a *lot* of ISPs do filter outgoing port 25 traffic.
However, it is beyond me why this is effective. Everyone and their dog will have their e-mail client (for most probably outlook/-express) configured to properly send all outgoing e-mail via. the ISP provided SMTP relay.
If a program uses the standard mail API in windows, those settings will be used and a mail will be transmitted properly through any defined relays. For some reason, the worms choose to implement their own SMTP layer directly atop of the socket layer, rather than saving the work and using the standard API. And *this* alone causes port 25 filtering to be effective.
The first worm that simply utilises the standard mail API will effectively bypass any port 25 blocking.
Why they don't do this already, is beyond me.
Maybe they put a GPS receiver and a huge radio transmitter on the sun, so that the sun can relay its location to earth... Oh wait, no, that wouldn't work...
:)
It's a mystery. It's not like it is difficult to determine the approximate direction of the most intensive light source (which should be the only positioning the dish would need).
I blame marketing
Point(s) taken :)
Thanks,
Oh yearh, a beautiful desktop environment on a crippled kernel, that'd be a real party... Yay!?!?
I guess I'm somehow missing out on how exactly running KDE (or anything else that could run on a proper OS) on windows would be "interesting".
Actually, Edward Telller claimed he did not feel bad about having invented the hydrogen bomb.
:)
Because, as he said, it is the first time in history that the most powerful weapon in existence had not been used in war.
Sure, war's bad and all that, but I did find his take on this pretty darn interesting
Yes, read what I wrote again.
25 [cubic meters / sec]
= 25.000 [liters / sec]
25.000 [liters/sec] / 5 [liters/revolution]
= 5000 [revolutions/sec]
0.1 [meter] radius roughly equals 0.6 meter circumference
Thus, as I wrote;
5000 [revolutions/sec] * 0.6 [meters/revoluion]
= 3000 [meters/sec]
which roughly equals mach-10
Just like before.
Hmm... 25 cubic meters per second of airflow.
;)
Let's say the volume of the smallest cylinder that contain the fan would be 1 liter (using round numbers here). With five fan blades, that would mean that the fan could move 5 liters of air per revolution.
That would mean something like 5000 revolutions per second.
Ok, so the radius of the fan is something like 0.1 meter (round numbers remember), giving approximately a peripheral speed of 3000 meters per second.
That's around mach-10.
Somehow I doubt the "Quiet CPU Cooler" sticker on the fan is going to hold true.
Nah, wait, somehow I just doubt a few of the numbers there
The cool thing about stable debian is, that it *doesn't* upgrade to the latest version of all the software.
:)
It just installs security updates.
That way, I don't need to worry about database upgrades, configuration file changes, API/protocol changes etc. etc. etc. Everything that ran before, runs afterwards, unchanged.
*that* is cool. If you're running production servers in the real world at least
I know he called that one. That doesn't make me feel any better though...
I think I should clarify that;
Debuggers are not illegal as such - they are only illegal to *use* for most purposes, with the notable exception of "research".
So you can argue we're bending the law more than breaking it, by using debuggers for, eh, debugging our own products. Same with disassemblers.
In any case, the law was not intended to outlaw software development entirely, it was only intended to outlaw software development that the MPAA did not endorse.
You know, when laws like this pass, I have this hope deep inside me, that the responsible politicians were bribed. Because, if they were bribed, there would be a rational explanation and a good reason (however immoral), as to how the law could pass.
If we assume that they were not bribed, that would make incompetence the only explanation. And that scares me - to think that someone with that amount of influence and responsibility could be incompetent to such levels. That scares me.
I hope simple greed did it. Unfortunately, I am most likely mistaken.
You see, sw patents are only a problem when you are starting up new business - if you are IBM (or Microsoft to some extent) already, then they are useful.
My point here being, that software patents are only 'stifling' if you intend to start up new business.
And you are only likely to realize this, if you realize that starting up new businesses is important for an economy to grow.
Back in the late '90s our government found out that Denmark should be a country of innovation, a high-tech economy so to speak - we cannot compete with china on industrial production costs anyway. So, in order to "boost" research they shut down the only government super computing center we had, sending researchers elsewhere to go beg for computing power.
To further strenghten our position as a nation of researchers and scientists, we have one of the most expensive but crappiest primary school systems in the western world - which is one thing, but the fact that anyone refuses to do anything about it underlines how important it is to the government to really position our country with a high-tech economy. Or not...
Copyright law was changed last year, to make it illegal to use or develop debuggers and disassemblers. I wrote to the minister in change of that decision letting him know that I and anyone else developing software would be breaking that law. Got some bullshit answer back which didn't address the problem, so now I'm practicing my right to "civil disobedience" every day on the job, along with everyone else in the software business in this country...
800 jobs is money right here right now. "Stifling" is in the eye of the beholder. For a government which is determined to break any initiative or start-up business, either indirectly thru neglect or directly thru law, it seems like it is not such a tough decision to make.
Oh, and add a photo opportunity with Bill and it's a done deal.
Dude, they're not trying to destroy anything in particular.
You can buy a box that will run Red Hat from them if you want - if you don't like Solaris under the CDDL, just go ahead and run Red Hat, or run the good ole binary Solaris.
It's not like they're hurting anyone in any way other than offering a product under a given license. They are not taking anything *away* from others.
If you don't like it, don't use it.
Just like every other product out there, be it GPL'ed, BSD'ed or evil capitalist proprietary.
Ok, a dish is a high-gain antenna. Is it because the antenna magically produces energy from nothing and amplifies the signal? No.
:)
Gain comes at a price.
The only way an antenna can produce gain, is, by limiting the directions in which it is effective.
A longer dipole (vertically mounted) becomes less effective in the vertical range - which means a long dipole that is perfectly vertical will not really transmit a lot of the energy upwards (and will therefore suck for satellite communication - which you don't care about, but which explains why vertically mounted high-gain dipoles are not used for satellite communication
A dish becomes even more effective by limiting its effectiveness in all other directions than "straight ahead". The better the dish, the narrower "straight ahead" becomes, and the higher the gain therefore becomes "straight ahead".
But you want signal over a large horizontal area, as I understand it. Yet people suggest dishes...
So, unless you want motorized dishes (either remotely controlled which would be a real pain for the user which would need to carry a remote control and continuously reposition the base station dish towards his location, or automatically homing on thermal activity or whatever - totally undoable on the budget you seem to have) on your base stations, don't consider dish antennas. They will be very efficient in a very limited direction, and ineffective everywhere else.
High gain dipoles might work for you, though.
Please, whatever you do, before endeavoring into alternative antenna configurations, make sure you understand what the implications of a given antenna design are (something a slashdotter or two seem to have momentarily forgotten, judging by the comments in this thread).
Absolutely correct (and his nonsence about common identifications of the "screen" you're working on being outdated, well, guess he never noticed the title bar in his windows...)
Also, take a look at the Orange book - it's from 1985, and close to 100% of what you find in there is as relevant and correct as ever, but unlike the user interface guidelines, the computing industry has not (except for a few notable exceptions) seemed to really converge towards compliance here.
(closest thing you get in a general purpose OS is Trusted Solaris, certified against the LSPP, which corresponds pretty much to the 'B2' profile from Orange book. Nobody ever made a general purpose OS that even approached B3 (let alone A1 and beyond) from Orange book).
With all the "computer security" fluff in the media these days, it's easy to feel disappointed at the "evolution" in the IT world when you read the 20 year old cook-book to how secure systems can be built.
Nobody cared enough. And people pay dearly for that today.