Basic Doubt About Ip Addresses

[H.O.D 0]

I have a basic doubt about how IP addresses work - is it based on the computer or on the connection? For example I have a broadband connection from one ISP and and I also use my mobile to connect to the internet on my computer. Will both the connections have the same IP address because they are being used on the same computer? And can someone detect that I am using two connections on the same computer? Please help me unravel these mysteries thanks a lot

[shadowx 0]

I just typed a huge reply but figured you wouldnt read it, it was damn long :)So the answers are thus:An ip address is given to the network card. IF you have one network card in your PC you get on address, if you have a hundred then each one gets its own unique IP, so you get 100 addresses. Which IP it gets is determined on the network. WIthout going into details a network is like a telephone number. It has a dialling or area code and then extra numbers. (around my area they start with 01708 then XXX XXX numbers) So if i have two networks on different subnets (dialling codes) and have a pc with two cards and connect one card to the first network and one to the second, different network, then the IP addresses will be very different. BUt if they are connected to the same network (perhaps i want twice as much bandwidth or speed) then they will be very similar, perhaps only the last number is different. So it is based on both the network card and the network. Usually the network card asks for an address and the network (a router/switch) is responsible for giving it one. Until the network gives it an address it doesnt actually have one.If you use the internet through a cable from your ISP and then through your phone as well you will have two completely different IPs, both will refer to your single computer however. This is because the IP is given to the network card, not the computer. And your mobile is acting as a network card hence it gets is own, unique, IP. So you have two different IPs.Can someone detect that you have two cards?Well that depends.... In your example with the internet connection and the mobile connection then probably not. However, if say you connected both connections to one network (EG if you had a router and put two cables from it into two cards on your PC) then possibly... Im not sure exactly how but possibly.Think of IP addresses like phone numbers, i expect it could be done. IPs arent mysterious they are controlled by strict rules, try a wikipedia search for "Internet Protocol"

[H.O.D 0]

Thanks for the response shadowx - I'm not using a router and if I'm not wrong I don't even use the network card - I have an external modem for broadband and the cell phone acts as a modem for the second connection. So in theory both have different IPs right? I checked online and saw that both indeed showed different IPs but I'm only concerned about if there is a way to detect that the same computer is being used. Oh well I'm not using it for anything dangerous and there is no loss even if it is detected. Thanks for the reply once again

[xpress 0]

You computer has a network card which connects your external modem to computer. When you connect to the internet, your modem will get an ip from the ISP (or chances are you have a static ip address too, which doesn't change every time you restart your broadband modem). When you connect your mobile to the internet, it will also a get an ip too. If you connect it through your computer using broadband (that means you connect to internet in mobile via bluetooth, or wireless) then your mobile will get a local ip address. (in the range 192.168.x.x). Or if you connect your mobile directly to the internet via your mobile service provider and use that connection on your mobile, your computer will have different ip.Actually every device that connects to a network(any network, not just internet) will have an ip, to uniquely identify iteself. If your computer connected to a local network of 10 computers, then each of them will have a unique ip even if they are not connected to internet. These ip addresses will be in the range 192.168.x.x These IP addresses are local, the local server assigns them these IPs to identify them on its network.

[nolan 0]

Others have already posted that the answer to this question is "no", but there are two small exceptions:

1. If you use some form of limited proxy, remote connectivity, or other Internet tunneling technology. This will make it so that, for the purpose of activity engaged in from the new connection, you have an IP address that is independent of your existing computer's IP.

2. If you are on a network that uses a dual- or multi-WAN setup, which can balance Internet traffic between two or more external connections for any connected PC. The number of IPs will be based on the number of external WAN connections.

There may be other exceptions, but these were the two that came to mind.

And can someone detect that I am using two connections on the same computer?

[shadowx 0]

The use of cookies etc... will track your computer, not the connection. So for example if i tell T17 to remember my login details that is saved to my computer using a cookie which is a small text file saves on your hard drive by the website. They are also used for adverts and to track visitors. So if you visited T17 and saved your login details using the landline phone connection and then accessed T17 using the broadband connection later it would "know" you are on the same computer.There are also ways the authorities have of tracing IP addresses through your ISP but they would only do that if you've been doing something you shouldnt have been. Plus they would need to track both IPs and then discover they link to the same personal details that you used to set the account up (IE you).

[Diffusr 0]

I have a basic doubt about how IP addresses work - is it based on the computer or on the connection? For example I have a broadband connection from one ISP and and I also use my mobile to connect to the internet on my computer. Will both the connections have the same IP address because they are being used on the same computer? And can someone detect that I am using two connections on the same computer? Please help me unravel these mysteries thanks a lot

Shadowx pretty much summed this one up with the point about each network card being assigned a unique ip address. Actually to be more precise and someone may already have said this but it is the MAC address media access control that is assigned with a logical ip address. The mac is the physical address burned into the network card in hex form. The internet layer of tcp/ip assigns this with a logical address that can be used by other routers and bridges across the internet.An interesting point to consider is whether your moblie phone mac is visible to the network or not. That would depend on how you are connecting to your computer. If you are using your mobile phone as a modem then yes the mobile phone mac would be visible and that would be assigned the logical ipv4 address. You can also have multiple connections on the same computer, so one machine can effectively have any number of ip addresses assigned to it. You may have done this yourself if you have connected to a wireless network and wired network at the same time - your computer would then have two different ip addresses as the wireless network interface card and the wired nic are separate entities on the same computer.