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Slashback: Bandwidth, Animation, Gruvin'
More news you can use on the @home front. Anubis333 writes: "After a while talking with customer support, I have learned that Comcast@Home (Soon to be ATT Broadband) has instituted a network-wide cap on user upload to 15KB! (Thats not much more than dialup) Also, they have now capped Usenet news access. What am I paying 50 dollars a month for again? More info on usenet here.
Upon even longer hold times, I found out that when Comcast switches over to ATT the cap will be set to 128KB and the usenet caps will be lifted, also they will support more groups. The full change over will be complete by the end of Feb. Any users in the Savannah Ga. Area, they will start here Jan. 15 and end in early feb. Call support for exact local dates if interested."
Yessir, about oh, yea big by a few more inches ... Dave contributed a link showing a side-by-side comparison of the current Apple laptop line, including the new bigger iBook. Shame about the resolution, though ...
By their fruits ye shall know them. zsazsa writes: "According to the St. Louis Post-Dispatch, Missouri Attorney General Jay Nixon has sued James Hibbits and Michael Webbs, the two founders of Linuxgruven for deceptive business practices. He alleges that interviewers were actually salespeople paid to enroll job applicants in training programs costing up to $3,150."
Would the FSF call Sun "GNU-minded"? maitas writes: "It seems that Sun has removed Solaris for Intel from its free download list. It's really sad to see a company that promotes its 'GNU minded' culture to go back on the few good things it had made. They even removed the Solaris source code from their site! Sad, sad, sad."
That them thar' book larnin' Stardance points to an interview at Salon with Steve Grand, in which the "designer of the artificial life program 'Creatures', talks about the stupidity of computers, the role of desire in intelligence and the coming revolution in what it means to be 'alive.'" You may remember Grand's book Creation: Life & How to Make It, reviewed on these pages. Speaking of reviews, several readers have contributed links to the New York Times' review of Lawrence Lessig's new book.
Many cable companies are starting to cap uploads at 128Kb...that's 15KB/sec. And if you think that's only a little faster than dial-up, try again. You can only get 28.8Kb/sec dialup upload.
I have several friends that have had a 128Kb/sec cap for a long time.
There will be no Intel version of Solaris 9. It is, in effect, a dead program. There's no reason for them to continue to provide it for download if it is going to be completely dropped momentarily. Soon enough it will no longer be for sale to commercial users.
And as for the source code...haven't they tried taking it down a couple times already? Probably if they get enough flame mail they will put it back up and try to claim it was a "mistake".
"(Man) tries to live his own life as if he were telling a story. But you have to choose: live or tell." --Sartre
So I have my iBook, but the resolution is too low, so I thought I'd get a PC laptop, but I don't want windows on it, so I'm thinking...Linux...that's the way to go, problem is when I go to take a class, I get defrauded, so now I'm thinking...Solaris Intel...that'll solve all my problems, so I go to download it and wouldn't you know sun removed it from their website, but that's ok cause I got this friend who has an ISO on his box at home and says I can download it, so I go to download it, but it turns out his upload speed is capped at 15K/sec which is just way too slow for pulling an entire ISO, so now I'm basically stuck with Windows (*sigh*)...oh well, at least /. recommended some cool books to read during the install.
"Don't blame me, I voted for Kodos!"
You should be greatful for that 1024*768! Why, I got a blue iBook with a 12" screen and 800*600. You youngans are such ingrates! Why, I'd step over my own mother to get two more inches and another step of res! Sides, if ya don't like tha bigga screen, you can still buy the smaller one, ya cheap bastard.
And another thing, when I was young...
;)
BlackGriffen
if you look at the comments in that thread, there are several from linuxgruven "employees" with similar User ID numbers, all saying how great the company is, and specifically mentioning the $45,000/yr figure.
start at comment 46309 and end at 469313.
Yes. Most cable ISPs restrict upstream bandwidth usage. However, with several easy steps under Linux, it's quite possible to get around these restrictions.
/boot by default on my distribution of Linux (Debian). The name of the file MUST EQUAL the name of the config file that the modem normally gets.
/etc/hosts entry for your cable modem's local IP (almost always 192.168.100.1). This is because when the modem requests its TFTP file from you, DNS will not be availble, and inet doesn't like not having DNS availble to resolve hostnames.
/var/log/daemon.log
Keep in mind that I've only tried this with DOCSIS modems. It may or may not work for you.
1. The first thing you want to do is find the IP address of the ISP's TFTP server. For me, this was the same IP as the HFC DHCP server. You can find that out by looking at your cable modem's mini webserver if availble. If not, play around with an SNMP client.
2. After you find the name of the TFTP server, get the name of the TFTP boot config file. This is availble through the same manner that you got the IP tothe real TFTP server.
3. Get the TFTP file. Use tftp to do this.
4. Decode the TFTP boot file using the docsis utility availble from http://docsis.sourceforge.net. The output will look something like this:
Main {
NetworkAccess 1;
ClassOfService {
ClassID 1;
MaxRateDown 1544000;
MaxRateUp 128000;
PriorityUp 0;
GuaranteedUp 0;
MaxBurstUp 0;
PrivacyEnable 0;
}
MaxCPE 3;
/* EndOfDataMarker */
}
5. Edit the config file to your own liking. You probably want to set "MaxBurstUp" to 0 to make this value unlimited.
6. Encode your own version of the file and place in the root level of your tftpd server, which is set to
7. You then need to create a
8. Create an alias address to the eth interface your cable modem's CPE interface is connected to. This IP address alias needs to be the same address as the real TFTP server's IP. You can do this like so:
ifconfig eth0:1 TftpServerAddress netmask 255.255.255.255
Notice the netmask setting. This is important. Otherwise you wind up having unwanted network routes which will break things. Plus, you only want the CM to have access to this IP, nobody else.
9. Create a static route to your cable modem from this "spoofed" address. This is needed so that you're "coming from" that spoofed IP when you communicate directly with your modem.
This can be accomplished by:
route add -host 192.168.100.1 gw TftpServerAddress
10. Make sure you have a time server enabled in your inet service, as well as the tftpd service.
11. Start watching your log files which will indicate a connection to the TFTP server. You can do this by:
tail -f
12. Start pinging your cable modem's CPE interface. This "poisons" the ARP cache and makes the modem think that TftpServerAddress is located on the CPE interface with a MAC address of your NIC. Then when it comes to connect to that IP, it will know where to find it.
13. Reset the modem while you are still pinging it. Make sure that the modem connects to your TFTP server and grabs the file. You can verify the upstream speed by querying the modem with an SNMP client after it comes back online:
snmpget 192.168.100.1 public transmission.127.1.1.3.1.3.1
The output should be equal to the value you used for MaxRateUp in your configuration file. If it is, make sure to destroy the IP alias on your network interface by doing:
ifconfig eth0:1 0
That sounds like an indirect result of the cap. The problem with most cable company equipment - the company that I work for included - is that upstream bandwidth that is available.
DOCSIS specifications - for US channel plan anyway - call for a 6mhz wide channel on the downstream. The downstream is anywhere from 91mhz to 750mhz (there are even some 850mhz cable plants). The 6mhz channel corresponds to a standard tv channel. With DOCSIS 1.0, the downstream can be either 64QAM or 256QAM. This is just the modulation of the digital signal as it is sent from the main facility to the subscriber. 256QAM gets you about 38mb/s of data transfer. 64QAM a little bit less.
Now, here is the crappy part. The upstream channel space from the subscriber back to the cable facilities is limited to 5-40 mhz. This is the width of the return path that the amplifiers in the system will receive and re-transmit. 0-10 is pretty much useless on most cable plants. That is the frequency space that short wave radios and the like use (a funny side note is that we once picked up a short wave religious station out of Boston using the signal ingress and amplification at our main facility). The rest is usefull for your upstream bandwidth on a DOCSIS system. The 1.0/1.1 spec states that you can use a frequency with a width of 200hz up to 3.2mhz. Obviously, the more space that you use, the more bandwidth that you have. There are also 2 types of modulation schemes that you can use. QAM16 and QPSK. QPSK is more reliable. QAM16 can carry more data. Most cable plants will use QPSK - your cable plant has to be air tight to use QAM16.
Anyway, if you use QPSK on a 3.2mhz wide channel for the upstream, you get about 5mb/s of available bandwidth. If you put 150 customers on this upstream port, and they all uploading files, emails, etc: then you could very well max out your upstream bandwidth.
That's why you have an upstream cap.
Joseph W. Breu