From a unix perspective there is no real difference between MacOS X and MacOS X Server, so I'm not sure what the point here is meant to be. MacOS X (workstation) is at its core the same as MacOS X Server (Darwin essentially), but more up-to-date and with the Aqua user-interface and a few other bits. In particular the BSD components and layout are in practice the same.
No it isn't!!! Darwin is completely different from OSX Server. It's like night and day. OSX Server is basically NextStep. Darwin is a brand new OS with parts taken from various different BSDs. Looking at the driver archetecture of OSX vs. OSX Server shows one just how many changes have been made. One of the biggest difference is that OSX Server is based on Mach2.5 and OSX gets an upgrade to Mach3 - but there are more.
A previous post does an excellent job of detailing the differences of the two OSes. It's rated 5 and is quite long so it should be hard to miss.
This also explains why OSX Server isn't getting upgraded - it would be pointless with the new (ie: Darwin) kernel about to make its enterence.
It looks like Daisy has been around for a while. Papers date back to 96. Looking at Transmeta I see that they were founded in 95. I'm not sure when Transmeta got their patents but it could very well be after IBM did much of their early research. IBM probably has a good fighting chance against any legal actions that might taken against them.
Or you could just use a telephone wire for 1/4 the cost. CAT5 has no advantage over a telephone line when using an RS-232 signal (unless you use very expensive shielded wire - costs a fortune!!)
For even greater distance you could wire up an RS232 to RS422 converter (very simple - did it for a lab in electronics class in under 5min.) Using a differential pair (ie: RS422) will greatly increase the distance you can go. See the link below:
http://www.rs485.com/rs485spec.html
This link does a great job at explaining the differences between the two. Here is a quote:
>>>RS422 (differential) was designed for greater distances and higher Baud rates than RS232. In its simplest form, a pair of converters from RS232 to RS422 (and back again) can be used to form an "RS232 extension cord." Data rates of up to 100K bits / second and distances up to 4000 Ft. can be accommodated with RS422.
Hmm. You are quite right. I've got 55km working and it works great. Mind you, you need an amp for those longer connections. Again, something every hammie would know.
In fact, the older Lucient stuff (don't know for sure about the ieee stuff) actually quotes 50km as being the maximum distance. The 5.8GHz stuff is supposed to go 80km (or so Lucient tells me in their spec sheet.)
I wouldn't even consider this a hack - it's designed to do it and it's within spec!!!! Ganted, most of the new stuff is geared for "in office" use hence their adds don't fucus on other applications. But still, do people not read the spec sheets? A different crowd I might understand but this is Slashdot - we're all geeks (Hum,hum But not me of course.);)
You can legally go ~50km with ieee802.11. Installing a 24db directional antenna is fine and won't put you over spec. Installing a 24db antenna plus a 1/2watt amp is even within spec (good for ~50km.)
Now if you move to a 10watt amp with a 30db antenna you are most certainly over spec!!! Mind you, you'll have a great connection.;)
( You should also be careful if standing in front of one of these setups. I'm not joking - they can cause serious harm. )
Willy (PS, this info is good for the US and Canada)
Very easy to implement. Wavelan stuff has built in Point to Point ability. I actually did this when working for a school district. I put an old 486 box with 2 wavelan cards on a mountaintop (486 is more reliable - no fans - less heat - cheap - don't need performance.) Several schools (that were not in direct line of sight of each other) connected to the box. Running Linux, it acted as a simple router forwarding the IP. I then configured a Linux router at each school to route IP through the wireless network. No real IPs were lost - the wireless network used private IPs. The Linux boxes at each school just implemented IP bridging.
Up in northern Canada, this was the _only_ way to connect some of the schools. Modems wouldn't work in several places due to the fact TELUS still uses some radio links. Hell, my parents can't get anything over 300baud on their 28.8 modem.
I should also mention that with the right amp and antenna, a 55km link is very reliable - even in a snow storm.;)
Ok, there are 14 frequency ranges that equipment can use. Granted they overlap, but even if you take that into account there are still 7 distinct frequency ranges available for use. In my experience (I networked 12 different schools together) there are few problems that can't easily be overcome.
Possibly you're on channel 1 and your neighbor is on channel 2? That right there would explain it - the channels overlap. Move yours to channel 10 (the more seperation the better but anything over 3 should work.) Note: this only applies if using a point-to-point connection or if there are several unrelated access-points available. (The frequency overlap is designed to allow for "roaming". Not used it your situation.)
Do both you and your neighbor connect to the same access-point? If so that would also explain it. Remember this is a shared 11Mb (ok, really about 4-6) connection. Kind of like a cable modem - other people using it will slow you down.
One thing about access points is that everyone is supposed to be able to "see" each other - just like ethernet. If two clients connect to the same access point but can't see each other then they might both try to talk to the access point at the same time - not going to work. The solution here it to put your access point into a special mode ("ad-hoc" or something that sounds like that.) When in this mode, the access point will boroadcast a message telling all nodes to be quiet so the one node can send the message without being interupted. If this isn't done everything will appear to work great - even if under heavy load from one node. But under a heavy load from several nodes it will come grinding to a halt. A very hard problem to troubleshoot!!
Now if this doesn't describe your situation then there are things you can do to solve the problem. For example, try rotating the polarity of both antennas (transmit/receive). This shoud issolate your system from the other allowing both to work, even if using the same frequency.
Much of this depends on who designed and setup the wireless network. If they're new to it they'll have made some mistakes (speaking from experience.) Most techs thinks it's sooo easy to setup and use but neglect to consider some small, but important points. It's kind of like a web server. While it's not that hard to install Linux + Apache, it takes a little more to configure it as a production web server - just like there is more to setting up a wireless network then plugging in an access point.
I'm going to cut this message short but rest assured, there are plenty of other ways to potentially solve your problem. If you give a more detailed description I might even be able to help out. My last employer really allowed me to really push the limits of 802.11. Now doesn't a 55km link to a mountain top sound like a cool project? Hmm, I liked that job.;)
Good point. Extension conflicts aren't the most logical thing to troubleshoot. And some of the problems that occur with Windows.....
Linux/Unix has the advantage that it usually works the way it was designed. If something goes wrong (which doesn't happen that often) it's easy to track down. The one problem with Linux/Unix is that most maintenence is far more difficult to administer. Dragging a Mac extension to the trash is easy - editing a.conf file isn't. (At the same time, knowing what extension to drag over is more or less "trial and error" while *NIX admins know exactly what.conf file to edit.)
So I guess there are two ways to look at this. Unix/Linux is easier if you know how to troubleshoot problems and are comfortable with the command line/unix. MacOS is great for those who are scared of a command prompt. If something goes wrong with a Mac, one can generally fix it without documentation.
Two different systems - two different users. I really like what MacOSX is doing for bringing the two together.
Using this same logic, why not compare four 500MHz PowerPC G4's to one Athlon? One Athlon actually costs more!! Load Linux onto these machines and which do you think will be faster - 2GHz of PowerPC or 1.2GHz of Thunderbird? On well threaded apps, the PowerPC would kick ass!!! (This is in theory - is it like this in real life?)
While this logic isn't actually flawed it just never turns out to be this way in the real world. First of all, someone actually has to make the machines (forget about that G4 idea.) I'm sure the AMD760 MBs will be out soon but, until they are, it really isn't a fair comparison. Also, don't forget about the additional hardware required to support dual CPUs - larger power supply, extra cooling, more expensive motherboard. The best "real life" test would be to take a computer manufacturer (like Gateway) and compare their offerings. Not a perfect comparison but at least it takes into account _all_ of the costs associated with building a computer.
PS: I got the Athlon price from this:
http://www.hiphardware.com/economics/cpuprices/ind ex.shtml
I'm sure it is slightly outdated and that it is now possible to get a better price. The G4 sells for $150.
Or is Apple waiting for 'the community' to come up with stuff like Powerbook support that Apple has already promised long ago.
Apple has a great model available for creating device drivers. I don't write them myself but I know people who do and they like it. All the docs + sample code are available on their web page.
Is there any development infrastructure besides a mailing list (see Mozilla's array of bugtracker, newsgroups, CVS, daily builds, docs, and so on.)
I don't have the web address handy but Apple does have a bug tracking page for Darwin. All known bugs are posted and assigned to various Apple engineers. I'm sure you could even eMail them if you wanted an update on the status of the fix or if you wanted to submit a new fix of your own.
Nobody's really going to care about NFS performance or mounting 200 different filesystems or whatever Linux-kernel people are worried about. And the consumer version won't even have a term window, so forget about classic Unix userspace stuff.
You're right about people not caring if it isn't the fastest OS on server tasks. Like any other OS, this will improve with age. But about the terminal window, I read a quote from Steve Jobs where he stated that the terminal app will be present in the final version. Not on the main desktop but it'll still be there.
Willy
Re:the only real Power chips are not in Apples
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No Love For Darwin?
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· Score: 1
>The IBM Power chips are far more advanced than the half-assed Motorola chips Apple is using. and that's why IBM is not playing with Apple and Motorola anymore - Motorola just doesn't give a shit, and didn't care to make improvements where IBM's architects saw fit.
Ahh, have you not discovered that different applications have different requirements? Is it not possible that Motorola is designing their chips for the people that actually buy them - the embeded market? Seriously though, how many CPU designs run at 500MHz with a four stage pipeline and are as powerful as a G4? Even without looking at power consumption or manufacturing costs there still is nothing that can touch a PowerPC (except possibly the StrongARM.) The P4 is designed for speed and has a 20 stage pipeline. It also costs a ton to produce and draws ~50w of power.
If you were building a cable modem what CPU would you consider more advanced?
>but given the 700MHz difference in clock for comparably priced processors
Can you buy a 1.2GHz Athlon for $150?
The problem isn't with the PowerPC, it's with Apple. I believe Motorola sells a 550MHz G4 for $150. IBM also has a 750MHz version (minus Altivec) that they're selling for under $150. Those are reasonable prices considering how well they perform when compared to say a 700MHz P3. I'm not saying the PowerPC is the fastest chip out there - just that it is priced well compared to the competition. This is especially true if you look at the lower speeds (400MHz~$75.)
I would love to be able to buy a PC with PowerPC chips in place of 8x86. I might have to buy 2, or even 4 CPUs to place in the motherboard but the performance would be great running Linux. With their low power requirements they wouldn't require any CPU fans (or even a bigger power supply.) This fact alone is a selling point for those wanting a quiet + reliable system. (I can't count the number of CPU fans I've replaced. I've even seen some CPUs burn up due to broken fans. This reminds me of early IBM pentium systems - they had no CPU fans and were very reliable!! )
The PowerPC is a great CPU and is the leader in it's class. Things will become even more interesting when the new G4e is released in January. Don't blame the PowerPC for mistakes made by Apple - it's actually a great CPU.
Willy
Re:Not nearly enough power to worry about delivery
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Wave Driven Generators
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· Score: 1
OK, got my facts wrong here. I messed the "James Bay Project" up with some other projects.
I did however find an OK link to some info that people might find useful. It mentions a 240MWatt generating plant off the coast of France.
But hey, if that little idea I proposed ever did get built (I think cold fusion will come around before anything like that could happen), it would be impressive!!
We're talking about 500kWatts. Don't get me wrong, it's great that we're using renewable resources in place of oil. I just question how much this will actually help. Especially when you consider that the average power produced will probably be under 100kW. 500kW is peak power and there's no way it can be maintained when depending on environmental factors.
Seeing that a toaster consumes just over 1kW, I seriously doubt this form of power generation will have any overall effect on oil consumption. Think of it this way, assuming a P4 draws 50W you would need one powerplant for ever 2000 CPUs. Throw in RAMBUS, a good video card, monitor,..... We're talking 1 power plant for every 1000 PCs. How realistic is that? Power produced on the West coast would never make it through LA so there's little need to worry about transporting it.
Another interesting idea for tidal power generation is the proposed James Bay Project. Now this will never happen due to environmental factors but would produce far more power then even the Hoover Dam. Let me explain...
James Bay is just off Hudson Bay in North Eastern Canada. Look at a globe and you'll see it, it's that big. Anyway, the entrance to the bay is very narrow so the idea is to build a dam across it. Now take the area of the bay, assume 8-10' for the tides (they're above average), the number of tides in 24hours (around 2 - anyone know exactly?) and you have a whole lot of water that would have to pass through the dam. Lets face it, anything that could make the Hoover Dam look small is pretty damn impressive.
The idea was proposed a while back but scuttled due to the environmental factors. Probably a good thing it never went through. Ah, if only...
Since wavelength at 66MHz is about 4.5 meters, I don't think transmission line effects are all that important on short 1 foot cable (yes I realize SCSI needs terminators but that is slightly different).
Just in case you didn't know, a 66MHz square wave is made up of several (ok, really unlimited) different sine waves. You need to look at the rising and falling times of the signal if you want to calculate the RF produced.
Also, look at an FM transmitter. One inch of wire is enough to transmit a signal!!! Even AM doesn't require that big an antenna while it operates at a blazing 1MHz. The 66MHz signal will most definitely be producing a ton of RF.
The ground lines are nothing more than shielding in this case.
Are you serious? You really think putting a wire next to another wire will provide shielding? No, sorry bud, that's just not how it works. Shielding can be provided by completely surrounding the transmission line with a ground wire - like with your TV cable or RCA wires. An extra wire does nothing to stop RF.
So why do people put ground wires by transmission wires? It's actually not usually like that. The two wires aren't positive + ground, they're a differential pair, like your ethernet cable. The idea being that one wire is more positive then the other. So then when a pile of RF comes along and jolts the voltage up in those lines by 20%, the data isn't lost because the relative voltage of the two lines isn't effected. The second line protects against data corruption, not RF production.
This reminds me of a cool lab I did back when I was in school. Our class wired several RS232-RS422 converters to connect to the serial ports of different PCs. We then connected them all to a single differential pair (ie, two wires). After writing some software we had our entire lab networked via the serial port! Ok, it sounds lame but was great fun to implement.
That would be great for Apple, but not too good for Motorola. They need the Altivec to have the G4 compete against DSPs. The Altivec instructions are cool but, you are right, L2 cache would be cooler. IBM is however making some CPUs like this. The last I heard they were at 750MHz. No Altivec but they have the SMP and FPU of the G4!
The chip is designed to be produced and run efficiently . That's right, designed for a small die size (lower production costs) and lower power consumption. You thing Apple could make an fannless iMac with a P4? I think not.
The G4 has a 4 stage pipeline (compared to 20 to the P4.) This is one of the reasons why it's so fast while only running at 500MHz (larger pipelines allow for greater speeds while decreasing equivalent performance.) It's also why it's got such a small die size and low power consumption. Now the G4e will move up to a 7 stage pipeline but that's still a far cry from the 20 the P4 has. This is good though. I would rather a good SMP OS using 2 CPUs at 1/2 the clockspeed rather then an equivalent chip costing twice and much and drawing four times the power. A dual 500G4 is faster then a 1GHz P3 when using a good OS and a threaded app. I seriously doubt a 1GHz P3 sells for less then $300 - a 500MHz G4 sells for ~$150.
It's my belief that if it weren't for Microsoft's crappy non-SMP operating system, the 8x86 chips of today would be much different then they currently are. Even just putting multiple CPU cores in one chip should result is a significant performance boost (given the same overall die size.) Linux would benefit greatly from a chip like this!!;)
Having said that I must admit Motorola screwed up the the G4 design. They made a very efficient chip that runs at a maximun of 500MHz. Problem is the yields are so low it makes for chips that cost more then they should.
----- I want my G4 for under $75!!!!
I know it sounds unreasonable, but technically quite possible with a modified chip design. I bet Nintendo is currently paying less then that! But the big question is, will it be the G4e? I hope Motorola learned something from this past disaster.....
>The only solution, therefore, would be for Apple to build some kind of hybrid machine with both a G4 and Pentium/Athlon on board.
How about an optional PCI card with a PowerPC processor? Not everyone will need legacy support. Many people just want to do their eMail and internet browsing. Making it optional would help reduce the initial sticker price.
>Yes, Intel has continually ramped up the megahertz of the Pentium (as has AMD), but the G4 has held its own in real-world performance
You're quite right, the higher megahertz come at a price. A longer pipeline, bigger die, greater power consumption, and greater cost just to name a few. Motorola really sells CPUs to the embeded market so they don't care that much about making an inefficient chip. But they could focus more on raw speed.... And I'm sure an 8x86 port would help motivate them some more. I doubt Apple would sell 8x86 equipment because the PowerPC is so cheap and allows for great designes due to it's low power consumption. The _threat_ of loosing Apple as a customer is however a good thing dispite how remote the possibility of it actually happening might be.
>Note that Carbon is not supposed to work on i386 now (while Darwin and the Cocoa environment does). Quartz (the window manager) either.
Hmm, I may very well be wrong but I believe Apple has ported move of the Carbon/Classic APIs to 8x86 for the quicktime version of windows.
As far as Quartz goes, I seriously doubt that Apple programmed it in assembly. More then likely it was some variant of C. Any assembly optimizations that might be incorporated into Quartz would probably have first been written in C. When doing an 8x86 port they'ld loose that assembly but should still be able to do the port because they'ld have the original C code.
Now I make this sound sooo easy. In reality I'm sure it would be a very complex job.
Whay I would love to see is for Apple to make a port of Quartz / Cocoa only. This would really push developers to support the Cocoa enviroment and wouldn't canabalize Mac sales that much because most of the Mac users out there will still want access to their Classic apps. One problem with this is that I heard, directly from an Apple employee, that Carbon and Cocoa are linked together. Sometimes a Cocoa API call will internally call a Carbon function. It makes sence - this why they don't have to make two copies of everything, but it also makes an 8x86 port that much more difficult.
Great explanation. I just have to add that the stuff can go much further then just a couple miles. Using legal equipment, I (with the help of a couple friends) networked three towns up in northern Canada. The longest shot was ~45km. It worked great and this was just using standard 1/2watt amps and 24db antennas. (And linux boxes to do the routing... One on a mountaintop.)
You can also buy 10watt amps and bigger (up to 6' diameter) antennas. These should significantly extend the range past the 50km mark. But be careful not to stand in front of those antennas for too long - 10watts of microwave radiation passing through your body isn't going to do your prostate any good.;)
I believe this product is targeted at paranoid, cost conscious, @Home users who don't have technical expertise. They save a few bucks by not having as much cabling and by using a PCI card doesn't require a power supply. This should drop the price when compared to the much better (but more expensive) externally boxed solutions.
Any real power user won't want their hub/firewall tied to their computer. Nor will a small business. The whole network would go down every time someone wants to upgrade their RAM or some foolish person in the office wants to save on the power bill by turning your computer off after you've gone home.
I personally use a 486/BSD solution. You're absolutely right, it's the way to go for those who know how to do it!!
I'm with ya. I also don't like the idea of always having to have my PC on.
I've setup a few picoBSD firewalls and they work great. The big advantage with a dedicated system is it doesn't matter what you do with your machine, the network will still be up. Try to add some additional RAM when using one of these cards... it's not gona work.
A dedicated 486 picoBSD firewall will also typically run without any fans or HDs. Sure there's the floppy disk but it only spins on boot up. Take out the video card and ide controller and you got yourself a little firewall that produces no noise and draws a fraction of the power that your typical/.'s PC would draw.
The idea of a firewall on a PCI card is great for the home user who knows nothing about Linux so it'll probably find some market share. I wouldn't have any problem recommending one to someone wanting to connect to @HOME.
A really cool idea would be to say take one of those IBM powerPC micocontrollers that come with built in dual 10/100 ethernet controllers and place that in a small box running LinuxPPC. Add a little 8 port hub and a LED display (a small one, like on a laser printer) and you would have a great firewall. Without services like telnet or ftp it would be _very_ secure. (Well that and you would probably have Linux on an EEPROM that would require a jumper change in order to be reprogrammed.;)
Hmmmm, one could easily incorporate a UPS into a small, low power unit like this. Just include a battery and have it plug in to a 12v power supply. But that's probably going a bit too far.
Ars Technica did a review on that Apple 22" display. The conclusion was that it was almost perfect. The problems were price (as expected) and the fact there was blur.
Now that Apple 22" is about as good as it gets for flat panel displays. Much better then most smaller (cheaper) displays as far as blur goes (or so the article states.) However, in the end Ars recommends that gamers stick with a CRT. The flat panels (regardless of brand or style) don't cut it for gaming. Great for office work though!!
The Radeon can also do this. The.18 micron process is great (I assume NVIA uses the same.) I just wish 3dfx would upgrade from their existing.25 micron fabs to.18. An accelerated Voodoo (moved to.18 micron) with lower power consumption would probably compete favorably against ATI and NVIA.
ATI hasn't had any real competition in the mobile market. I don't think NVIA will steal too much from ATI with the mobile Radeon a month or two away. They will however help speed up the previously stagnant mobile accelerator market. Competition is a very good thing!!
Slashdot Mirror
No it isn't!!! Darwin is completely different from OSX Server. It's like night and day. OSX Server is basically NextStep. Darwin is a brand new OS with parts taken from various different BSDs. Looking at the driver archetecture of OSX vs. OSX Server shows one just how many changes have been made. One of the biggest difference is that OSX Server is based on Mach2.5 and OSX gets an upgrade to Mach3 - but there are more.
A previous post does an excellent job of detailing the differences of the two OSes. It's rated 5 and is quite long so it should be hard to miss.
This also explains why OSX Server isn't getting upgraded - it would be pointless with the new (ie: Darwin) kernel about to make its enterence.
Willy
It looks like Daisy has been around for a while. Papers date back to 96. Looking at Transmeta I see that they were founded in 95. I'm not sure when Transmeta got their patents but it could very well be after IBM did much of their early research. IBM probably has a good fighting chance against any legal actions that might taken against them.
Willy
Or you could just use a telephone wire for 1/4 the cost. CAT5 has no advantage over a telephone line when using an RS-232 signal (unless you use very expensive shielded wire - costs a fortune!!)
For even greater distance you could wire up an RS232 to RS422 converter (very simple - did it for a lab in electronics class in under 5min.) Using a differential pair (ie: RS422) will greatly increase the distance you can go. See the link below:
http://www.rs485.com/rs485spec.html
This link does a great job at explaining the differences between the two. Here is a quote:
>>>RS422 (differential) was designed for greater distances and higher Baud rates than RS232. In its simplest form, a pair of converters from RS232 to RS422 (and back again) can be used to form an "RS232 extension cord." Data rates of up to 100K bits / second and distances up to 4000 Ft. can be accommodated with RS422.
Willy
Hmm. You are quite right. I've got 55km working and it works great. Mind you, you need an amp for those longer connections. Again, something every hammie would know.
;)
In fact, the older Lucient stuff (don't know for sure about the ieee stuff) actually quotes 50km as being the maximum distance. The 5.8GHz stuff is supposed to go 80km (or so Lucient tells me in their spec sheet.)
I wouldn't even consider this a hack - it's designed to do it and it's within spec!!!! Ganted, most of the new stuff is geared for "in office" use hence their adds don't fucus on other applications. But still, do people not read the spec sheets? A different crowd I might understand but this is Slashdot - we're all geeks (Hum,hum But not me of course.)
Willy
You can legally go ~50km with ieee802.11. Installing a 24db directional antenna is fine and won't put you over spec. Installing a 24db antenna plus a 1/2watt amp is even within spec (good for ~50km.)
;)
Now if you move to a 10watt amp with a 30db antenna you are most certainly over spec!!! Mind you, you'll have a great connection.
( You should also be careful if standing in front of one of these setups. I'm not joking - they can cause serious harm. )
Willy (PS, this info is good for the US and Canada)
Very easy to implement. Wavelan stuff has built in Point to Point ability. I actually did this when working for a school district. I put an old 486 box with 2 wavelan cards on a mountaintop (486 is more reliable - no fans - less heat - cheap - don't need performance.) Several schools (that were not in direct line of sight of each other) connected to the box. Running Linux, it acted as a simple router forwarding the IP. I then configured a Linux router at each school to route IP through the wireless network. No real IPs were lost - the wireless network used private IPs. The Linux boxes at each school just implemented IP bridging.
;)
Up in northern Canada, this was the _only_ way to connect some of the schools. Modems wouldn't work in several places due to the fact TELUS still uses some radio links. Hell, my parents can't get anything over 300baud on their 28.8 modem.
I should also mention that with the right amp and antenna, a 55km link is very reliable - even in a snow storm.
Willy
Ok, there are 14 frequency ranges that equipment can use. Granted they overlap, but even if you take that into account there are still 7 distinct frequency ranges available for use. In my experience (I networked 12 different schools together) there are few problems that can't easily be overcome.
;)
Possibly you're on channel 1 and your neighbor is on channel 2? That right there would explain it - the channels overlap. Move yours to channel 10 (the more seperation the better but anything over 3 should work.) Note: this only applies if using a point-to-point connection or if there are several unrelated access-points available. (The frequency overlap is designed to allow for "roaming". Not used it your situation.)
Do both you and your neighbor connect to the same access-point? If so that would also explain it. Remember this is a shared 11Mb (ok, really about 4-6) connection. Kind of like a cable modem - other people using it will slow you down.
One thing about access points is that everyone is supposed to be able to "see" each other - just like ethernet. If two clients connect to the same access point but can't see each other then they might both try to talk to the access point at the same time - not going to work. The solution here it to put your access point into a special mode ("ad-hoc" or something that sounds like that.) When in this mode, the access point will boroadcast a message telling all nodes to be quiet so the one node can send the message without being interupted. If this isn't done everything will appear to work great - even if under heavy load from one node. But under a heavy load from several nodes it will come grinding to a halt. A very hard problem to troubleshoot!!
Now if this doesn't describe your situation then there are things you can do to solve the problem. For example, try rotating the polarity of both antennas (transmit/receive). This shoud issolate your system from the other allowing both to work, even if using the same frequency.
Much of this depends on who designed and setup the wireless network. If they're new to it they'll have made some mistakes (speaking from experience.) Most techs thinks it's sooo easy to setup and use but neglect to consider some small, but important points. It's kind of like a web server. While it's not that hard to install Linux + Apache, it takes a little more to configure it as a production web server - just like there is more to setting up a wireless network then plugging in an access point.
I'm going to cut this message short but rest assured, there are plenty of other ways to potentially solve your problem. If you give a more detailed description I might even be able to help out. My last employer really allowed me to really push the limits of 802.11. Now doesn't a 55km link to a mountain top sound like a cool project? Hmm, I liked that job.
Willy
Good point. Extension conflicts aren't the most logical thing to troubleshoot. And some of the problems that occur with Windows.....
.conf file isn't. (At the same time, knowing what extension to drag over is more or less "trial and error" while *NIX admins know exactly what .conf file to edit.)
Linux/Unix has the advantage that it usually works the way it was designed. If something goes wrong (which doesn't happen that often) it's easy to track down. The one problem with Linux/Unix is that most maintenence is far more difficult to administer. Dragging a Mac extension to the trash is easy - editing a
So I guess there are two ways to look at this. Unix/Linux is easier if you know how to troubleshoot problems and are comfortable with the command line/unix. MacOS is great for those who are scared of a command prompt. If something goes wrong with a Mac, one can generally fix it without documentation.
Two different systems - two different users. I really like what MacOSX is doing for bringing the two together.
Willy
Using this same logic, why not compare four 500MHz PowerPC G4's to one Athlon? One Athlon actually costs more!! Load Linux onto these machines and which do you think will be faster - 2GHz of PowerPC or 1.2GHz of Thunderbird? On well threaded apps, the PowerPC would kick ass!!! (This is in theory - is it like this in real life?)
d ex.shtml
While this logic isn't actually flawed it just never turns out to be this way in the real world. First of all, someone actually has to make the machines (forget about that G4 idea.) I'm sure the AMD760 MBs will be out soon but, until they are, it really isn't a fair comparison. Also, don't forget about the additional hardware required to support dual CPUs - larger power supply, extra cooling, more expensive motherboard. The best "real life" test would be to take a computer manufacturer (like Gateway) and compare their offerings. Not a perfect comparison but at least it takes into account _all_ of the costs associated with building a computer.
PS: I got the Athlon price from this:
http://www.hiphardware.com/economics/cpuprices/in
I'm sure it is slightly outdated and that it is now possible to get a better price. The G4 sells for $150.
Willy
Apple has a great model available for creating device drivers. I don't write them myself but I know people who do and they like it. All the docs + sample code are available on their web page.
Is there any development infrastructure besides a mailing list (see Mozilla's array of bugtracker, newsgroups, CVS, daily builds, docs, and so on.)
I don't have the web address handy but Apple does have a bug tracking page for Darwin. All known bugs are posted and assigned to various Apple engineers. I'm sure you could even eMail them if you wanted an update on the status of the fix or if you wanted to submit a new fix of your own.
Nobody's really going to care about NFS performance or mounting 200 different filesystems or whatever Linux-kernel people are worried about. And the consumer version won't even have a term window, so forget about classic Unix userspace stuff.
You're right about people not caring if it isn't the fastest OS on server tasks. Like any other OS, this will improve with age. But about the terminal window, I read a quote from Steve Jobs where he stated that the terminal app will be present in the final version. Not on the main desktop but it'll still be there.
Willy
>The IBM Power chips are far more advanced than the half-assed Motorola chips Apple is using. and that's why IBM is not playing with Apple and Motorola anymore - Motorola just doesn't give a shit, and didn't care to make improvements where IBM's architects saw fit.
Ahh, have you not discovered that different applications have different requirements? Is it not possible that Motorola is designing their chips for the people that actually buy them - the embeded market? Seriously though, how many CPU designs run at 500MHz with a four stage pipeline and are as powerful as a G4? Even without looking at power consumption or manufacturing costs there still is nothing that can touch a PowerPC (except possibly the StrongARM.) The P4 is designed for speed and has a 20 stage pipeline. It also costs a ton to produce and draws ~50w of power.
If you were building a cable modem what CPU would you consider more advanced?
Willy
>but given the 700MHz difference in clock for comparably priced processors
Can you buy a 1.2GHz Athlon for $150?
The problem isn't with the PowerPC, it's with Apple. I believe Motorola sells a 550MHz G4 for $150. IBM also has a 750MHz version (minus Altivec) that they're selling for under $150. Those are reasonable prices considering how well they perform when compared to say a 700MHz P3. I'm not saying the PowerPC is the fastest chip out there - just that it is priced well compared to the competition. This is especially true if you look at the lower speeds (400MHz~$75.)
I would love to be able to buy a PC with PowerPC chips in place of 8x86. I might have to buy 2, or even 4 CPUs to place in the motherboard but the performance would be great running Linux. With their low power requirements they wouldn't require any CPU fans (or even a bigger power supply.) This fact alone is a selling point for those wanting a quiet + reliable system. (I can't count the number of CPU fans I've replaced. I've even seen some CPUs burn up due to broken fans. This reminds me of early IBM pentium systems - they had no CPU fans and were very reliable!! )
The PowerPC is a great CPU and is the leader in it's class. Things will become even more interesting when the new G4e is released in January. Don't blame the PowerPC for mistakes made by Apple - it's actually a great CPU.
Willy
OK, got my facts wrong here. I messed the "James Bay Project" up with some other projects.
a pper.htm
I did however find an OK link to some info that people might find useful. It mentions a 240MWatt generating plant off the coast of France.
http://www.calpoly.edu/~cm/studpage/nsmallco/cl
But hey, if that little idea I proposed ever did get built (I think cold fusion will come around before anything like that could happen), it would be impressive!!
Willy
Seeing that a toaster consumes just over 1kW, I seriously doubt this form of power generation will have any overall effect on oil consumption. Think of it this way, assuming a P4 draws 50W you would need one powerplant for ever 2000 CPUs. Throw in RAMBUS, a good video card, monitor, ..... We're talking 1 power plant for every 1000 PCs. How realistic is that? Power produced on the West coast would never make it through LA so there's little need to worry about transporting it.
Another interesting idea for tidal power generation is the proposed James Bay Project. Now this will never happen due to environmental factors but would produce far more power then even the Hoover Dam. Let me explain...
James Bay is just off Hudson Bay in North Eastern Canada. Look at a globe and you'll see it, it's that big. Anyway, the entrance to the bay is very narrow so the idea is to build a dam across it. Now take the area of the bay, assume 8-10' for the tides (they're above average), the number of tides in 24hours (around 2 - anyone know exactly?) and you have a whole lot of water that would have to pass through the dam. Lets face it, anything that could make the Hoover Dam look small is pretty damn impressive.
The idea was proposed a while back but scuttled due to the environmental factors. Probably a good thing it never went through. Ah, if only...
Willy
Just in case you didn't know, a 66MHz square wave is made up of several (ok, really unlimited) different sine waves. You need to look at the rising and falling times of the signal if you want to calculate the RF produced.
Also, look at an FM transmitter. One inch of wire is enough to transmit a signal!!! Even AM doesn't require that big an antenna while it operates at a blazing 1MHz. The 66MHz signal will most definitely be producing a ton of RF.
The ground lines are nothing more than shielding in this case.
Are you serious? You really think putting a wire next to another wire will provide shielding? No, sorry bud, that's just not how it works. Shielding can be provided by completely surrounding the transmission line with a ground wire - like with your TV cable or RCA wires. An extra wire does nothing to stop RF.
So why do people put ground wires by transmission wires? It's actually not usually like that. The two wires aren't positive + ground, they're a differential pair, like your ethernet cable. The idea being that one wire is more positive then the other. So then when a pile of RF comes along and jolts the voltage up in those lines by 20%, the data isn't lost because the relative voltage of the two lines isn't effected. The second line protects against data corruption, not RF production.
This reminds me of a cool lab I did back when I was in school. Our class wired several RS232-RS422 converters to connect to the serial ports of different PCs. We then connected them all to a single differential pair (ie, two wires). After writing some software we had our entire lab networked via the serial port! Ok, it sounds lame but was great fun to implement.
Willy
That would be great for Apple, but not too good for Motorola. They need the Altivec to have the G4 compete against DSPs. The Altivec instructions are cool but, you are right, L2 cache would be cooler. IBM is however making some CPUs like this. The last I heard they were at 750MHz. No Altivec but they have the SMP and FPU of the G4!
Willy
The G4 has a 4 stage pipeline (compared to 20 to the P4.) This is one of the reasons why it's so fast while only running at 500MHz (larger pipelines allow for greater speeds while decreasing equivalent performance.) It's also why it's got such a small die size and low power consumption. Now the G4e will move up to a 7 stage pipeline but that's still a far cry from the 20 the P4 has. This is good though. I would rather a good SMP OS using 2 CPUs at 1/2 the clockspeed rather then an equivalent chip costing twice and much and drawing four times the power. A dual 500G4 is faster then a 1GHz P3 when using a good OS and a threaded app. I seriously doubt a 1GHz P3 sells for less then $300 - a 500MHz G4 sells for ~$150.
It's my belief that if it weren't for Microsoft's crappy non-SMP operating system, the 8x86 chips of today would be much different then they currently are. Even just putting multiple CPU cores in one chip should result is a significant performance boost (given the same overall die size.) Linux would benefit greatly from a chip like this!! ;)
Having said that I must admit Motorola screwed up the the G4 design. They made a very efficient chip that runs at a maximun of 500MHz. Problem is the yields are so low it makes for chips that cost more then they should.
----- I want my G4 for under $75!!!!
I know it sounds unreasonable, but technically quite possible with a modified chip design. I bet Nintendo is currently paying less then that! But the big question is, will it be the G4e? I hope Motorola learned something from this past disaster.....
Willy
>The only solution, therefore, would be for Apple to build some kind of hybrid machine with both a G4 and Pentium/Athlon on board.
How about an optional PCI card with a PowerPC processor? Not everyone will need legacy support. Many people just want to do their eMail and internet browsing. Making it optional would help reduce the initial sticker price.
>Yes, Intel has continually ramped up the megahertz of the Pentium (as has AMD), but the G4 has held its own in real-world performance
You're quite right, the higher megahertz come at a price. A longer pipeline, bigger die, greater power consumption, and greater cost just to name a few. Motorola really sells CPUs to the embeded market so they don't care that much about making an inefficient chip. But they could focus more on raw speed.... And I'm sure an 8x86 port would help motivate them some more. I doubt Apple would sell 8x86 equipment because the PowerPC is so cheap and allows for great designes due to it's low power consumption. The _threat_ of loosing Apple as a customer is however a good thing dispite how remote the possibility of it actually happening might be.
Willy
>Note that Carbon is not supposed to work on i386 now (while Darwin and the Cocoa environment does). Quartz (the window manager) either.
Hmm, I may very well be wrong but I believe Apple has ported move of the Carbon/Classic APIs to 8x86 for the quicktime version of windows.
As far as Quartz goes, I seriously doubt that Apple programmed it in assembly. More then likely it was some variant of C. Any assembly optimizations that might be incorporated into Quartz would probably have first been written in C. When doing an 8x86 port they'ld loose that assembly but should still be able to do the port because they'ld have the original C code.
Now I make this sound sooo easy. In reality I'm sure it would be a very complex job.
Whay I would love to see is for Apple to make a port of Quartz / Cocoa only. This would really push developers to support the Cocoa enviroment and wouldn't canabalize Mac sales that much because most of the Mac users out there will still want access to their Classic apps. One problem with this is that I heard, directly from an Apple employee, that Carbon and Cocoa are linked together. Sometimes a Cocoa API call will internally call a Carbon function. It makes sence - this why they don't have to make two copies of everything, but it also makes an 8x86 port that much more difficult.
Willy
Great explanation. I just have to add that the stuff can go much further then just a couple miles. Using legal equipment, I (with the help of a couple friends) networked three towns up in northern Canada. The longest shot was ~45km. It worked great and this was just using standard 1/2watt amps and 24db antennas. (And linux boxes to do the routing... One on a mountaintop.)
;)
You can also buy 10watt amps and bigger (up to 6' diameter) antennas. These should significantly extend the range past the 50km mark. But be careful not to stand in front of those antennas for too long - 10watts of microwave radiation passing through your body isn't going to do your prostate any good.
Willy
I believe this product is targeted at paranoid, cost conscious, @Home users who don't have technical expertise. They save a few bucks by not having as much cabling and by using a PCI card doesn't require a power supply. This should drop the price when compared to the much better (but more expensive) externally boxed solutions.
Any real power user won't want their hub/firewall tied to their computer. Nor will a small business. The whole network would go down every time someone wants to upgrade their RAM or some foolish person in the office wants to save on the power bill by turning your computer off after you've gone home.
I personally use a 486/BSD solution. You're absolutely right, it's the way to go for those who know how to do it!!
Willy
I'm with ya. I also don't like the idea of always having to have my PC on.
/.'s PC would draw.
;)
I've setup a few picoBSD firewalls and they work great. The big advantage with a dedicated system is it doesn't matter what you do with your machine, the network will still be up. Try to add some additional RAM when using one of these cards... it's not gona work.
A dedicated 486 picoBSD firewall will also typically run without any fans or HDs. Sure there's the floppy disk but it only spins on boot up. Take out the video card and ide controller and you got yourself a little firewall that produces no noise and draws a fraction of the power that your typical
The idea of a firewall on a PCI card is great for the home user who knows nothing about Linux so it'll probably find some market share. I wouldn't have any problem recommending one to someone wanting to connect to @HOME.
A really cool idea would be to say take one of those IBM powerPC micocontrollers that come with built in dual 10/100 ethernet controllers and place that in a small box running LinuxPPC. Add a little 8 port hub and a LED display (a small one, like on a laser printer) and you would have a great firewall. Without services like telnet or ftp it would be _very_ secure. (Well that and you would probably have Linux on an EEPROM that would require a jumper change in order to be reprogrammed.
Hmmmm, one could easily incorporate a UPS into a small, low power unit like this. Just include a battery and have it plug in to a 12v power supply. But that's probably going a bit too far.
Willy
Ars Technica did a review on that Apple 22" display. The conclusion was that it was almost perfect. The problems were price (as expected) and the fact there was blur.
Now that Apple 22" is about as good as it gets for flat panel displays. Much better then most smaller (cheaper) displays as far as blur goes (or so the article states.) However, in the end Ars recommends that gamers stick with a CRT. The flat panels (regardless of brand or style) don't cut it for gaming. Great for office work though!!
Willy
The Radeon can also do this. The .18 micron process is great (I assume NVIA uses the same.) I just wish 3dfx would upgrade from their existing .25 micron fabs to .18. An accelerated Voodoo (moved to .18 micron) with lower power consumption would probably compete favorably against ATI and NVIA.
ATI hasn't had any real competition in the mobile market. I don't think NVIA will steal too much from ATI with the mobile Radeon a month or two away. They will however help speed up the previously stagnant mobile accelerator market. Competition is a very good thing!!
Willy
Ballard has been sending home units to Japan for testing purposes. It won't be long... ;)