SharePro said:
You dont tell the ISP what IP you want. The radius server and dhcp/static configuration of the router is what defines your IP.
As I noted above, I was talking about Cable internet providers, running the DOCSIS standard. Those networks use CMTS which is similar to DSLAM (RAS Server) divided into geographical areas where the cable network is spread.
The whole concept behind uncapping is registering with a MAC address that doesn't appear on your local CMTS allowing to gain access to the internet.
Unlike DSL, Cable networks use MPLS mechanism to route their traffic, due to fast performance and lower overhead compared to ATM's mechanism used by most of the DSL providers.
The major flaw of MPLS is that you don't have as much visibility over the data for traffic management, and this where modded modems comes to play.
SharePro said:
Stealing internet access via wireless pops, or sniffing networks, etc., is not to be confused with spoofing. Spoofing is making the destination think your source IP is something other than it really is.
For the majority of cable internet users you don't have the ability to get a new IP if you want to because the CMTS negotiates directly with the DHCP to assign a valid IP from the IP Pool (There are different dhcp servers depending on the diversity of ISPs available to a given cable network) by using your modems MAC address (The ISP's RADIUS server updates the CMTS's regularly with valid MAC addresses and their respective packages, also known as cable modem configuration files).
In short, after the Cable modem send the dhcp discovery packet, the cmts passes it through to all the dhcp servers (much like different ISPs on a given cable network, although its inaccurate) available, but only the one who has the modems MAC address (sent in the CHADDR field of the dhcp offer packet) responds with a correct dcp offer, resulting in dhcp ack, the final phase of the registration.
The RADIUS servers in this case, are used to make sure that there is no duplicates of MAC address, and making roaming a lot easier.
Again,
its not like sending a packet from IP X.X.X.X as a packet from X.X.X.Y rather than making you appear as somebody's else CPE, but its a great way to achieve what the OP has asked to do with the referrals.
Think of it as of masquerading yourself as your neighbor. Most of ISPs provide up to 9 CPEs per MAC address, meaning you can get up to 8 different IPs registered under somebody else name without kicking him off the network.
