I live in an area where almost all apartments (3000) are owned jointly in small unions (150-300 apartments per union). So all the smaller unions stuck their heads together, put up a lan, phone lines and cable tv covering the entire area. Then we buy the TV signal, a rather large internet line and phone lines out and act as service provider to ourselves...Phone line and tv signal is $6 each
hah! i love it! basically, you're selling it to yourselves for no profit to yourselves!
AOL Time Warner to buy out companies like Earthlink and put restrictions on EVERYONE's internet and cable services.
Actually when you get a cable modem with Time warner you can choose Earthlink as your provider instead of Roadrunner TW. They had to do it otherwise they would get in trouble for hogging the lines. I just hope roadrunner stays seprate from aol crapband, thats the day i would switch to dsl if they made me use aol.
Am I not sending my MAC adress when I make requests?
MAC addresses are mainly used by hubs, certain bridges and switches locally.
The MAC addresss is on level 2 of the OSI model (the Data-Link layer).
Routers are on level 3 of the OSI model (the Network Layer), and don't actively deal too much with protocols "below" level 3. They deal with IP routes, IPX, etc. although some ARP stuff happens (mapping an IP addy to a MAC addy, but not the other way around)
I don't think the MAC address is "routable" through your NAT router.
More details:
Your mac address does not go past your router. The router operates at layer 3, so when your router receives a frame with an ip address that is outside of the lan, it will strip the frame header off and put its own back. The destination and source ip address stay the same from host to host, but at each layer three device, the mac addresses are stripped. Then the router puts it's mac as the source and the foreign router's mac as source.
As for your isp being able to see how many pc's you have connected, I don't think they can. If you look at the settings for your ip addresses(if yours are like mine) then they are all 10.0.0.0 (or 192.168.xxx.xxx or 172.16.xxx.xxx which are private) which is an unrouted ip address. I'm guessing that the software puts the gateway ip address in as the source address.
"Oh no", he said, "You need to install the software or you won't be able to go online."
My cable modem installer was pretty cool. He just said "Here's a configuration CD to install a web browser. I wouldn't use this on a mac because it is full of bugs and will crash." I didn't and had a shiny new coaster too!
How can they tell how many boxes are behind a NAT router?
Easy. The same way the NAT router knows which computer to sent the return packets to! I am not exactly WHAT the data is, but as part of the NAT translation, the router will tag the packet with some sort of code identifying the machine on your network that sent it.
This tag is also included in any reply packets, which is how the NAT router can send the packet back to your machine.
The cable company could be decoding the headders of every packet and looking for tags, but this would require one hell of a system... Although it is possible, the company is more likely to be using it as a scare tactic - or only checking random connections at random times.
Edit.. Hmmm I'll change that easy to a mybe....
Quote:
The router saves the computer's non-routable IP address and port number to an address translation table. The router replaces the sending computer's non-routable IP address with the router's IP address. The router replaces the sending computer's source port with the port number that matches where the router saved the sending computer's address information in the address translation table. The translation table now has a mapping of the computer's non-routable IP address and port number along with the router's IP address.
All that travels outside your lan is NAT's IP address, and 'position' in NAT of originating IP, how can they determine how many machines are connected to the network behind NAT?
look:
1. My Computer (192.168.1.5) sends a packet to 209.90.100.10 (originating port is 345)
2. NAT enters that info in it's routing table, something like:
3. NAT stripes Private IP and port info, and replaces private IP with gateway IP, and originating port with table position of that entry in it's table, so what travels outside looks something like that:
Now all we need is a NAT router with a continuously changing router table that assigns random "position" numbers no matter how many computers are on the net.
So how can your ISP look up how many machines are connected to NAT ?
While the IP address and source ports are indeed changed as they pass through the NAT gateway, other values are not.
Two methods are used. First, different operating systems use different initial "time-to-live" (TTL) values for their packets. The TTL value is decremented every time the packet is passed on by a router. If this value reaches zero, the router discards the packets.
Windows starts their packets off with a TTL of 128. This means that the ISPs can expect to receive packets from your machine with this TTL. However, when the packet passes through your NAT router, it will decrement this TTL value before passing on the packet. When the ISP sees a packet with a TTL of 127, they know it has passed through a router of some sort. If the source address of the packet matches the address they gave you, they know the packet has been NAT'ted.
In addition, they can use the "identifier" field of the IP packet to determine the number of hosts behind the NAT router. When a computer boots, it randomly picks an number. Every time it sends an IP packet, it increments the number and uses that as the IP identifier.
Since each computer behind your NAT router will start with a different random number, they can detect "flows" in the packets that pass through their network. For example, they'll receive 5 packets number 4,5,6,7,8, and another 5 packets numbered 6656,6657,6658,6659,6660. They can see two distinct series of numbers being incremented, so they know you have two computers behind your NAT router.
So, as you can see, it is actually very trivial to determine that you are using a NAT gateway, and count how many computers you have behind it.
I believe I have heard that some BSDs implement NAT where the IP TTL and identifier fields are also "translated", which would defeat this method. But I know of no commercial NAT gateways that do this. Perhaps in the future this could be a selling point?
What I want to know is how Earthlink could change their network to disallow you to utilize a router. Just HOW?
I don't think they are making their network incompatible. I think they are detecting that you do it and terminating your service if they catch you. Most cable companies already do this, but this is the first time I've seen a DSL company do it. I don't understand the reasoning, personally.
Well, that's not true. I suspect they oversubscribe the amount of bandwidth they have connecting to the internet backbone, so they don't want you using the full bandwidth you are paying for. *sigh* Things like this tick me off.
Cablevision cable modem (CT) for me. Unlimited down, and over 1MB/s up (based on me scp'ing 100MB files to a server in FL).
"Only 1 per cable modem" is for me to. Not that I got the Linksys wireless setup or anything... Ocasionally they do IP scans... but I have only 1 to the outside world, so I am good to go. No webserving though (unless you forward stuff to port 8080 or something).
I mainly just peruse the boards here because I'm a novice and cant really contribute intelligently but I glean a bit of knowledge here and there.
For example, With some general help from the posts and some specific help from certain members, I was able to successfully network my G4 with my two son's Windows computers via an asante router. Its the only real "technical" thing Ive done. Hell, I even made my own Ethernet cables!!! I ran them all through the house; neatly and discreetly I must say.
We've all been enjoying Earthlink Broadband (via AOLTW cable) for about a year now. And I was so proud of myself. And I wasnt just trying to save the $10 a month but all the networking solutions they offered had a disadvantage. (like sending the signal through the electrical system.)
I'll pay the extra $10 if its fair.
They wont try to get the $ retroactively, will they?
I'm using SBC near San Francisco. When I signed up I mentioned I would be using a router and they said fine. No problem.
I now have two DSL lines coming in, one SBC directly and one Earthlink riding on SBC. (long story, one's corporate, one's private) The Earhtlink line has an Asante Router. I haven't seen the email from Earthlink mentioning routers.
Both work fairly well. Earthlink email seems to go down frequently late at night. I guess they're doing some sort of maintenance. I now ignore that and just wait an hour or so then the emails go out as usual.
I live in an area where almost all apartments (3000) are owned jointly in small unions (150-300 apartments per union). So all the smaller unions stuck their heads together, put up a lan, phone lines and cable tv covering the entire area. Then we buy the TV signal, a rather large internet line and phone lines out and act as service provider to ourselves...Phone line and tv signal is $6 each
hah! i love it! basically, you're selling it to yourselves for no profit to yourselves!
freaky, but i like it!
One could call it a variation of the ?kibbutz? theme, I heard of somewhat similar arrangements in actual kibbutz's.
While this Our-Own-ISP.org? thingee might not be idyllic (for nothing is) it sounds not half as bad an arrangement as some of the other anecdotes on this thread.
I take it you cats didn't read the slashdot article on how to determine how many compueters are behind a router? It was highly technical. It is possible. It can also be worked around, once again restoring your privacy, though not by today's hardware routers.
AFA Earthlink actually figuring this out, you give them far toomuch credit. this is a scare tactic, plain and simple.
Cablevision cable modem (CT) for me. Unlimited down, and over 1MB/s up (based on me scp'ing 100MB files to a server in FL).
"Only 1 per cable modem" is for me to. Not that I got the Linksys wireless setup or anything... Ocasionally they do IP scans... but I have only 1 to the outside world, so I am good to go. No webserving though (unless you forward stuff to port 8080 or something).
US$40.00 per month.
You should be getting more than just "1MB/s up." I have Cablevision too, though here in NY, and I get a good 8 to 10 megabits, with uploads at around 1 megabits (helps when ordering with iPhoto javascript:smilie('') ). Try using this tool to check your speed @ http://nyc.speakeasy.net
Comments
Originally posted by Anders
I live in an area where almost all apartments (3000) are owned jointly in small unions (150-300 apartments per union). So all the smaller unions stuck their heads together, put up a lan, phone lines and cable tv covering the entire area. Then we buy the TV signal, a rather large internet line and phone lines out and act as service provider to ourselves...Phone line and tv signal is $6 each
hah! i love it! basically, you're selling it to yourselves for no profit to yourselves!
freaky, but i like it!
Originally posted by filmmaker2002
AOL Time Warner to buy out companies like Earthlink and put restrictions on EVERYONE's internet and cable services.
Actually when you get a cable modem with Time warner you can choose Earthlink as your provider instead of Roadrunner TW. They had to do it otherwise they would get in trouble for hogging the lines. I just hope roadrunner stays seprate from aol crapband, thats the day i would switch to dsl if they made me use aol.
Originally posted by Anders
Am I not sending my MAC adress when I make requests?
MAC addresses are mainly used by hubs, certain bridges and switches locally.
The MAC addresss is on level 2 of the OSI model (the Data-Link layer).
Routers are on level 3 of the OSI model (the Network Layer), and don't actively deal too much with protocols "below" level 3. They deal with IP routes, IPX, etc. although some ARP stuff happens (mapping an IP addy to a MAC addy, but not the other way around)
I don't think the MAC address is "routable" through your NAT router.
More details:
Your mac address does not go past your router. The router operates at layer 3, so when your router receives a frame with an ip address that is outside of the lan, it will strip the frame header off and put its own back. The destination and source ip address stay the same from host to host, but at each layer three device, the mac addresses are stripped. Then the router puts it's mac as the source and the foreign router's mac as source.
As for your isp being able to see how many pc's you have connected, I don't think they can. If you look at the settings for your ip addresses(if yours are like mine) then they are all 10.0.0.0 (or 192.168.xxx.xxx or 172.16.xxx.xxx which are private) which is an unrouted ip address. I'm guessing that the software puts the gateway ip address in as the source address.
Originally posted by iPeon
"Oh no", he said, "You need to install the software or you won't be able to go online."
My cable modem installer was pretty cool. He just said "Here's a configuration CD to install a web browser. I wouldn't use this on a mac because it is full of bugs and will crash." I didn't and had a shiny new coaster too!
How can they tell how many boxes are behind a NAT router?
Easy. The same way the NAT router knows which computer to sent the return packets to! I am not exactly WHAT the data is, but as part of the NAT translation, the router will tag the packet with some sort of code identifying the machine on your network that sent it.
This tag is also included in any reply packets, which is how the NAT router can send the packet back to your machine.
The cable company could be decoding the headders of every packet and looking for tags, but this would require one hell of a system... Although it is possible, the company is more likely to be using it as a scare tactic - or only checking random connections at random times.
Edit.. Hmmm I'll change that easy to a mybe....
The router saves the computer's non-routable IP address and port number to an address translation table. The router replaces the sending computer's non-routable IP address with the router's IP address. The router replaces the sending computer's source port with the port number that matches where the router saved the sending computer's address information in the address translation table. The translation table now has a mapping of the computer's non-routable IP address and port number along with the router's IP address.
From: http://www.cisco.com/warp/public/556/nat-cisco.shtml
Originally posted by Gargoyle
The cable company could be decoding the headders of every packet and looking for tags....
I wonder if this decoding of packet headers is against the DMCA (i.e., Digitial Millennium Copyright Act)?
All that travels outside your lan is NAT's IP address, and 'position' in NAT of originating IP, how can they determine how many machines are connected to the network behind NAT?
look:
1. My Computer (192.168.1.5) sends a packet to 209.90.100.10 (originating port is 345)
2. NAT enters that info in it's routing table, something like:
position: 1234, originating IP:192.168.1.5, originating port: 345.
3. NAT stripes Private IP and port info, and replaces private IP with gateway IP, and originating port with table position of that entry in it's table, so what travels outside looks something like that:
originating ip: gateway's IP, originating port: 1234
4. Return packet has an destination IP of your gateway, and destination port: 1234.
5. Nat translates it back to 192.168.1.5, port 345
So how can your ISP look up how many machines are connected to NAT ?
I probably oversimplified it, and there may be a way, but i don't think these guys do that.
or at least not in the way suggested.
I'm sure someone will be able to explain it better.
Originally posted by piwozniak
I'm sure someone will be able to explain it better.
Actually, that was pretty good.
position: 1234, originating IP:192.168.1.5, originating port: 345.
Now all we need is a NAT router with a continuously changing router table that assigns random "position" numbers no matter how many computers are on the net.
Originally posted by piwozniak
Gargoyle.
So how can your ISP look up how many machines are connected to NAT ?
While the IP address and source ports are indeed changed as they pass through the NAT gateway, other values are not.
Two methods are used. First, different operating systems use different initial "time-to-live" (TTL) values for their packets. The TTL value is decremented every time the packet is passed on by a router. If this value reaches zero, the router discards the packets.
Windows starts their packets off with a TTL of 128. This means that the ISPs can expect to receive packets from your machine with this TTL. However, when the packet passes through your NAT router, it will decrement this TTL value before passing on the packet. When the ISP sees a packet with a TTL of 127, they know it has passed through a router of some sort. If the source address of the packet matches the address they gave you, they know the packet has been NAT'ted.
In addition, they can use the "identifier" field of the IP packet to determine the number of hosts behind the NAT router. When a computer boots, it randomly picks an number. Every time it sends an IP packet, it increments the number and uses that as the IP identifier.
Since each computer behind your NAT router will start with a different random number, they can detect "flows" in the packets that pass through their network. For example, they'll receive 5 packets number 4,5,6,7,8, and another 5 packets numbered 6656,6657,6658,6659,6660. They can see two distinct series of numbers being incremented, so they know you have two computers behind your NAT router.
So, as you can see, it is actually very trivial to determine that you are using a NAT gateway, and count how many computers you have behind it.
I believe I have heard that some BSDs implement NAT where the IP TTL and identifier fields are also "translated", which would defeat this method. But I know of no commercial NAT gateways that do this. Perhaps in the future this could be a selling point?
John
[Edit: fixed some grammar issues.
Originally posted by drewprops
What I want to know is how Earthlink could change their network to disallow you to utilize a router. Just HOW?
I don't think they are making their network incompatible. I think they are detecting that you do it and terminating your service if they catch you. Most cable companies already do this, but this is the first time I've seen a DSL company do it. I don't understand the reasoning, personally.
Well, that's not true. I suspect they oversubscribe the amount of bandwidth they have connecting to the internet backbone, so they don't want you using the full bandwidth you are paying for. *sigh* Things like this tick me off.
John
"Only 1 per cable modem" is for me to. Not that I got the Linksys wireless setup or anything...
US$40.00 per month.
For example, With some general help from the posts and some specific help from certain members, I was able to successfully network my G4 with my two son's Windows computers via an asante router. Its the only real "technical" thing Ive done. Hell, I even made my own Ethernet cables!!! I ran them all through the house; neatly and discreetly I must say.
We've all been enjoying Earthlink Broadband (via AOLTW cable) for about a year now. And I was so proud of myself. And I wasnt just trying to save the $10 a month but all the networking solutions they offered had a disadvantage. (like sending the signal through the electrical system.)
I'll pay the extra $10 if its fair.
They wont try to get the $ retroactively, will they?
(ps, pscates, was one who helped, thank you)
I now have two DSL lines coming in, one SBC directly and one Earthlink riding on SBC. (long story, one's corporate, one's private) The Earhtlink line has an Asante Router. I haven't seen the email from Earthlink mentioning routers.
Both work fairly well. Earthlink email seems to go down frequently late at night. I guess they're doing some sort of maintenance. I now ignore that and just wait an hour or so then the emails go out as usual.
Originally posted by rok
Originally posted by Anders
The great force of socialism from below.
[?]
Hmmm? mutated multi-directional anarcho-syndicalism perhaps?
I live in an area where almost all apartments (3000) are owned jointly in small unions (150-300 apartments per union). So all the smaller unions stuck their heads together, put up a lan, phone lines and cable tv covering the entire area. Then we buy the TV signal, a rather large internet line and phone lines out and act as service provider to ourselves...Phone line and tv signal is $6 each
hah! i love it! basically, you're selling it to yourselves for no profit to yourselves!
freaky, but i like it!
One could call it a variation of the ?kibbutz? theme, I heard of somewhat similar arrangements in actual kibbutz's.
While this Our-Own-ISP.org? thingee might not be idyllic (for nothing is) it sounds not half as bad an arrangement as some of the other anecdotes on this thread.
AFA Earthlink actually figuring this out, you give them far toomuch credit. this is a scare tactic, plain and simple.
Originally posted by yzedf
Cablevision cable modem (CT) for me. Unlimited down, and over 1MB/s up (based on me scp'ing 100MB files to a server in FL).
"Only 1 per cable modem" is for me to. Not that I got the Linksys wireless setup or anything...
US$40.00 per month.
You should be getting more than just "1MB/s up." I have Cablevision too, though here in NY, and I get a good 8 to 10 megabits, with uploads at around 1 megabits (helps when ordering with iPhoto javascript:smilie('