Most GSM networks can already carry data at 9.6kilobits, 14.4kilobits, or 43.2kilobits (using time-slot combining - HSCSCD). Some networks have GPRS extensions which allow packet switching at 40kilobits.
In other words, the networks have no problem with data.
Using FreeBSD after experience with Linux is actually a good idea. You will find it a bit more challenging than Linux, but the rewards will be *improved* stability and performance in general. (From my experience in various situations, especially under heavy load).
I know KDE2.2, XMMMS, and the MSN client will run fine. I also know most source-code apps will compile in general. Also, FreeBSD does have Linux binary compatibility (to an extent). However, if you don't thrash your machine much, you will probably prefer Linux.
In short, put some time into learning about it and FreeBSD really is a fantastic OS. I would recommend it to tech-savvy people anyday. And it's constantly getting better (not dying:-P).
Perhaps TV shows can add random, unnoticable artifacts to the video to prevent this device from working? (the artifacts mean frames are no longer duplicate).
Here in Melbourne, Australia some of our "broadband" providers have similar policies, so I've always wondered how they might look at addressing NAT.
Although NAT masks all computers behind the firewall with it's external IP address, by examining the traffic, there are clues.
For example, let's say there are multiple instant messengers (eg ICQ, MSN) behind your firewall. If there are at least 2 of the same type, it generally means there are multiple users. Of course this isn't necessarily true though, if you have a *NIX computer this is easily done, or even Windows XP.
Let's say your firewall is a Linux/FreeBSD/whatever box. Nmapping or similar _may_ reveal this, and _may_ also determine its uptime. A long uptime is often an indicator of a firewall, since most people don't turn them off. Of course, lot's of people don't turn their PCs off either.
In general sniffing traffic might provide some clues as to what is going on at your end of the service.
These are just a few ideas, however none of them offer real proof of NAT, just some indicators. I'm sure there are legal implications (eg privacy) both in the US and in Australia on examining your network traffic.
Yeah it's not as obvious as first, but it's actually pretty simple.
OK here's an example: our gateway is 192.168.0.1 with lan interface eth0 and internet interface eth1. We want to redirect port 21 (FTP) to the machine 192.168.0.10
First of all, we need to add a rule matching incoming data to port 21. We use the PREROUTING chain in the NAT table:
This says: in the network address translation table and the chain that deals with incoming data prior to routing, and if the data is coming in from the internet and wants to go to TCP port 21 (ftp), DNAT (destination network address translate) it to transparently make it go to 192.168.0.10
Here's a generic template:
iptables -t nat -A PREROUTING -i [net interface] [selection rules - proto, port] -j DNAT --to-destination [ip on lan]
You can also redirect to a different port number, in the above example to redirect to 192.168.0.10 port 321 it would be:
--to-destination 192.168.0.10:321
As for this being an FAQ, I am aware of no such references on IPTables, and it doesn't matter. I think the manual page provides more than sufficient information to get you started. If you don't understand it, then you should not be administering a gateway of any kind!
oh great by the time I had posted this two anonymous cowards have posted it already, one with the answer, now i look redundant even though i didnt intend to be
The current workaround gets around this problem by disabling 4M (2M?) pages (PSE). Hence we go back to 4K pages, and mapping large slabs of VM is a little slower and wastes memory (we need another Page table for each slab of 4M) and obviously more TLB misses/space wasted, because to touch the whole 4M region, the CPU needs to do up to 1024 page table lookups instead of 1.
As discussed this may have performance implications.
According to the AMD docs, the problem is only when flushing TLB entries with INVLPG and the page is a 4M page, _and_ the virtual address's bit 21 is set (which does not affect the 4M block of memory the address is in - eg: 0x400000 (2^22) vs 0x600000 (2^22|2^21) are both in the second 4M block).
Hence, when invlpg'ing a VA we just need to INVLPG(address&~(1 (leftshift) 21)). This only requires a single ANDL instruction. But we need to distinguish a 4M page first though, so I don't know?
Heck maybe we should just do it the FreeBSD way and recursively map the Pagedir:-)
Optus cable is only available in patchy areas of metropolitan Sydney and Melbourne, last time I heard.
It's not just the area you live in, for me (in Melbourne), the Optus cable runs 50m away on the main road, but cannot come into my street due to underground cabling restrictions.
I highly doubt it. It's January 20th now (AEDT) and the release is scheduled for 26/01/2002. I doubt 6 days is sufficient time to do something as major as an XF86 upgrade. So, they would never make such a change in this stage of the "stablization".
Start reading the MBR, then follow the chain of execution until you are deep into the kernel...
That's how I started on the FreeBSD kernel and the Linux kernel.
Sure at the first there's some dependencies - and you are sent on a journey through about 20 H files just to find one #define ition, and to know A you need to know B, which requires C, but it worked for me.
You could always use a mobile (cell!) phone and plug in a hands-free kit. Of course, this may be impractical in some countries where mobile call rates make it too expensive.
Did you search for every instance of the word "New Zealand" in the article just to label me a troll? Well you still missed the most obvious one of all.
And yeah, the grammatical error was more of a typo as I spent about 10 seconds making that post.
Something I feel like asking as 2.4.17 (bz2) trickles down the connection at 0.2K/sec from Australia's Planetmirror...
The kernel's are posted in both GZ and BZ2 formats. What do you guys mostly use? I can't see much point these days with having the Gzip format, I mean is there still a point to downloading it? Or even having them available in that format?
From what I can see, removing the Gzipped versions
*reduces network congestion
*saves space on the mirrors
*saves space on local storage (yeah only a couple megs)
Of course, it requires more processing time to extract, but that seems to be no big deal these days. I'm pretty sure everyone has bzip2 installed , and those who don't can easily get it, so that can't be a problem.
So is it really just traditional reasons it's posted in Gzipped format? Tell me if I've missed something. It would be interesting to know what everyone thinks about this.
No, a process when in userspace cannot hog the CPU. Even if a process does not sleep on a wait-queue, say the program consists of:
for (;;);
It will be forced off the current CPU when its counter expires. The period of time depends on its nice value. The counter is decremented each clocktick, and a re schedule() happens when the counter is found to be =0.
The only way a program can hog the CPU if it is running real-time (SCHED_FIFO), but only superuser processes can do this.
Slashdot Mirror
Did you read the article.
Moore's law says double in approximately 18 months, and they are after a 1000 times increase, but I highly doubt exactly 1000.
Most GSM networks can already carry data at 9.6kilobits, 14.4kilobits, or 43.2kilobits (using time-slot combining - HSCSCD). Some networks have GPRS extensions which allow packet switching at 40kilobits.
In other words, the networks have no problem with data.
Perhaps calloc() on FreeBSD marks the page as "to be zeroed" on first touch?
Whereas Linux's calloc() actually zeroes the area manually?
--jquirke
Using FreeBSD after experience with Linux is actually a good idea. You will find it a bit more challenging than Linux, but the rewards will be *improved* stability and performance in general. (From my experience in various situations, especially under heavy load).
:-P).
I know KDE2.2, XMMMS, and the MSN client will run fine. I also know most source-code apps will compile in general. Also, FreeBSD does have Linux binary compatibility (to an extent). However, if you don't thrash your machine much, you will probably prefer Linux.
In short, put some time into learning about it and FreeBSD really is a fantastic OS. I would recommend it to tech-savvy people anyday. And it's constantly getting better (not dying
--jquirke
I can't believe we've made it this far without a debate on the spelling of Aluminium.
--jquirke
Perhaps TV shows can add random, unnoticable artifacts to the video to prevent this device from working? (the artifacts mean frames are no longer duplicate).
--jquirke
Too right. Moderators aren't dumb. We don't need to be told what is a troll and what isn't.
Nothing annoys me more than
^^ MOD PARENT UP ^^
or MOD PARENT -1 TROLL
--jquirke
Because it's a very happening kind of place. Try living here, you'll see what I mean.
Here in Melbourne, Australia some of our "broadband" providers have similar policies, so I've always wondered how they might look at addressing NAT.
Although NAT masks all computers behind the firewall with it's external IP address, by examining the traffic, there are clues.
For example, let's say there are multiple instant messengers (eg ICQ, MSN) behind your firewall. If there are at least 2 of the same type, it generally means there are multiple users. Of course this isn't necessarily true though, if you have a *NIX computer this is easily done, or even Windows XP.
Let's say your firewall is a Linux/FreeBSD/whatever box. Nmapping or similar _may_ reveal this, and _may_ also determine its uptime. A long uptime is often an indicator of a firewall, since most people don't turn them off. Of course, lot's of people don't turn their PCs off either.
In general sniffing traffic might provide some clues as to what is going on at your end of the service.
These are just a few ideas, however none of them offer real proof of NAT, just some indicators. I'm sure there are legal implications (eg privacy) both in the US and in Australia on examining your network traffic.
--jquirke
Yeah it's not as obvious as first, but it's actually pretty simple.
OK here's an example: our gateway is 192.168.0.1 with lan interface eth0 and internet interface eth1. We want to redirect port 21 (FTP) to the machine 192.168.0.10
First of all, we need to add a rule matching incoming data to port 21. We use the PREROUTING chain in the NAT table:
iptables -t nat -A PREROUTING -i eth1 -p tcp --dport 21 -j DNAT --to-destination 192.168.0.10
This says: in the network address translation table and the chain that deals with incoming data prior to routing, and if the data is coming in from the internet and wants to go to TCP port 21 (ftp), DNAT (destination network address translate) it to transparently make it go to 192.168.0.10
Here's a generic template:
iptables -t nat -A PREROUTING -i [net interface] [selection rules - proto, port] -j DNAT --to-destination [ip on lan]
You can also redirect to a different port number, in the above example to redirect to 192.168.0.10 port 321 it would be:
--to-destination 192.168.0.10:321
As for this being an FAQ, I am aware of no such references on IPTables, and it doesn't matter. I think the manual page provides more than sufficient information to get you started. If you don't understand it, then you should not be administering a gateway of any kind!
The stereo is in a hideaway spot in the center of the car so when someone looks in, it's not there
/. reader
... unless they're a
--jquirke
the largest Australian metropolitan city of Sydney
Actually Melbourne is the largest city in terms of land area, which is more relevant in this case, although it has a slightly smaller population.
--JQuirke
oh great by the time I had posted this two anonymous cowards have posted it already, one with the answer, now i look redundant even though i didnt intend to be
For those who couldn't spend a couple of minutes writing a Perl or C program I did (bored) and here's the base4->Alpha translation.
:-) - not that bored
to win a scholarship
from the university of lethbridge
do the math
formula:
find the sum of all decimal
digits appearing in the natural
numbers from one to one million
inclusive
contest entries must be
received by december 13/31/01
to enter online: visit
www.uleth.ca
and submit your
answer
mail: send you answer along
with your name full address and
phone number to go figure what
magazine 93 lombard avenue
winnipeg mb r3b3b1
And no, i dont have the answer
--JQuirke
The current workaround gets around this problem by disabling 4M (2M?) pages (PSE). Hence we go back to 4K pages, and mapping large slabs of VM is a little slower and wastes memory (we need another Page table for each slab of 4M) and obviously more TLB misses/space wasted, because to touch the whole 4M region, the CPU needs to do up to 1024 page table lookups instead of 1.
:-)
As discussed this may have performance implications.
According to the AMD docs, the problem is only when flushing TLB entries with INVLPG and the page is a 4M page, _and_ the virtual address's bit 21 is set (which does not affect the 4M block of memory the address is in - eg: 0x400000 (2^22) vs 0x600000 (2^22|2^21) are both in the second 4M block).
Hence, when invlpg'ing a VA we just need to INVLPG(address&~(1 (leftshift) 21)). This only requires a single ANDL instruction. But we need to distinguish a 4M page first though, so I don't know?
Heck maybe we should just do it the FreeBSD way and recursively map the Pagedir
Any ideas? Will this work?
--JQuirke
Optus cable is only available in patchy areas of metropolitan Sydney and Melbourne, last time I heard.
It's not just the area you live in, for me (in Melbourne), the Optus cable runs 50m away on the main road, but cannot come into my street due to underground cabling restrictions.
I highly doubt it. It's January 20th now (AEDT) and the release is scheduled for 26/01/2002. I doubt 6 days is sufficient time to do something as major as an XF86 upgrade. So, they would never make such a change in this stage of the "stablization".
--JQ
Start reading the MBR, then follow the chain of execution until you are deep into the kernel...
That's how I started on the FreeBSD kernel and the Linux kernel.
Sure at the first there's some dependencies - and you are sent on a journey through about 20 H files just to find one #define ition, and to know A you need to know B, which requires C, but it worked for me.
--jq
cellulars stil suffer from extreemly limited bandwith
:-(
Many GSM networks around the world now have the General Packet Radio (GPRS) extensions enabled which offers a much faster packet-switched connection to your wireless device (40kibibits). GPRS is charged by volume, not time, and you always stay connected.
This is the kind of technology that will allow wireless-device gaming to take-off, at least outside North America
You could always use a mobile (cell!) phone and plug in a hands-free kit. Of course, this may be impractical in some countries where mobile call rates make it too expensive.
Obviously, then, you don't have a title bar.
Did you search for every instance of the word "New Zealand" in the article just to label me a troll? Well you still missed the most obvious one of all.
And yeah, the grammatical error was more of a typo as I spent about 10 seconds making that post.
I hate to do this, but the country is New Zealand not New Zealands - I definitely know this - I spend 18 months of my life there.
:-)
This might look like Flamebait/Troll, but much worse would happen if we misspelled "Americca"
"unlimited" broadband in Australia via Telstra and Optus is ~60-80 AUD / month. That's US$ 30-45.
How much do you guys pay?
Something I feel like asking as 2.4.17 (bz2) trickles down the connection at 0.2K/sec from Australia's Planetmirror...
The kernel's are posted in both GZ and BZ2 formats. What do you guys mostly use? I can't see much point these days with having the Gzip format, I mean is there still a point to downloading it? Or even having them available in that format?
From what I can see, removing the Gzipped versions
*reduces network congestion
*saves space on the mirrors
*saves space on local storage (yeah only a couple megs)
Of course, it requires more processing time to extract, but that seems to be no big deal these days. I'm pretty sure everyone has bzip2 installed , and those who don't can easily get it, so that can't be a problem.
So is it really just traditional reasons it's posted in Gzipped format? Tell me if I've missed something. It would be interesting to know what everyone thinks about this.
No, a process when in userspace cannot hog the CPU. Even if a process does not sleep on a wait-queue, say the program consists of:
for (;;);
It will be forced off the current CPU when its counter expires. The period of time depends on its nice value. The counter is decremented each clocktick, and a re schedule() happens when the counter is found to be =0.
The only way a program can hog the CPU if it is running real-time (SCHED_FIFO), but only superuser processes can do this.