IP address?

[Spicuzza]

It is my understanding that every computer on the internet has a unique IP address. So regardless of someone's screen name the computer is identified by the IP address.

Also, my understanding is that regardless of mulitple screen names the IP address will always be the same on the same computer.

Can anyone point me in the right direction?

[Greg12]

Yes you are correct.

IP's do change however. If you have a dial up modem they change everytime u get online.


If you have cable or DSL, your IP may change every month or so.

Internet servers IP are static, they do not change.

When you type in "Yahoo.com" your computer checks it's local cache (called a hosts file) and sees if it has yahoo's ip. If it doesn't, it has to ask the ISP's DSN resolution software for the IP and then "call" that IP and wait for a response.

Your screen name only applies to a certain place.

Like no one on the net, unless from VCDhelp would know u as "SPicuzza", however everyone would u know by ur IP.


BTW, those ads that say "your computer is brodcasting it's IP", BS, if u rn't brodcasting, u rn't on the net.

[AND1]

Is there a way to hide your IP address or change it? I know there's programs and sort of stuff to do it any anoymize (sp) I think. But let's say you are banned from a forum and they banned your IP. Is there anyway to get around this and get back on? Or if you don't want a site or forum to see your IP is there a way to block it.

If so, can you tell me how or point me in the right direction. I really dont want to download useless programs or sign up for that anoynomizer stuff becuase I did try it and went back to a forum I was banned to see if I can get back on and they still blocked me so that's useless too.

[sterno]

Your IP address is how data gets to your machine. It's possible (and not really all that hard) to create packets that appear to come from another IP address, but if you do that the machine you contact will try to send the response back to the IP you spoofed. The only way to hide it is to use a proxy of some sort, your machine connects to the proxy and the proxy connects to the destination.

The problem there is that as I recall most web proxies include a header that says "I'm a proxy, the machine requesting this is A.B.C.D". Well-known proxies that don't do that (like anonymizer.com, which is very well known and has been for a few years) are often blocked as soon as any site starts needing to ban IPs.

If you want a new IP, try using a modem. Many broadband services also offer a dial-up account. If you're on cable/DSL using DHCP you might also be able to explicitly release the IP and request another one through your DHCP client. However, you will likely be assigned the same IP again.

[Spicuzza]

Let me ask the question this way. Can mulitple users on the same forum be assigned the exacted same IP address from AOL?

The reason that I asked is the fact that we have continuous nuisance posters on the High School message board that keep coming back under different screen names with a different e-mail address.

Also, within a two hour period three differrent messages were posted under three different screen names but all had the same IP address 64.12.96.199

Can someone explain this to me? How can that be? I understand dial up modems are assigned randomly everytime you log on but what are the chances of different people randomly getting the exact same IP address?

[sterno]

Also, within a two hour period three differrent messages were posted under three different screen names but all had the same IP address 64.12.96.199

Can someone explain this to me? How can that be? I understand dial up modems are assigned randomly everytime you log on but what are the chances of different people randomly getting the exact same IP address?

First off, that IP address looks like it's one of AOL's web proxy servers (it's named "cache-mtc-ak02.proxy.aol.com"). Many people in that area who dial in and use AOL's browser will appear to come from that IP.

Even if it weren't a proxy, it could be the same person using more than one name, it could be different people on the same computer with different names, it could be different people on different computers behind a broadband connection-sharing machine, etc.

Furthermore, dynamic IPs are not assigned randomly from all possible IP addresses, they're assigned from a (usually small) range. People living in the same area and dialing in to the same ISP will be assigned IPs from the same range. Also, the IP addresses are not necessarily assigned randomly, sometimes the first available address in the range will be assigned. That leads to less randomness.

[Spicuzza]

Sterno,

Thanks for the reply. Unfortunatly that actually makes the case worse if muliple people are assigned the exact same IP address within short periods of time from the same AOL server.

It makes it appear on the message board that the same person is posting under different screen names which could still be the case.

I just found it odd that within a two hour period three messages were posted with the exact same IP address. From what I'm understanding you are saying that's possible due to the fact the particular server has a relative small range of addresses and assigns the same one if available.

Anyway, thanks to all for the imput.

[sterno]

You missed the main point, which was the first thing I wrote. That IP address is an AOL web proxy. AOL users in that area will probably all appear to be connecting from that IP, regardless of what IP they might actually have.

[gmatov]

In addition, if anyone cares, attbi, cable, issues a 3 day lease on your IP address. Should you go to >Start>Run>winipcfg>your net card, you will find your IP address, and below that, "lease obtained, lease expires".
Now, my dialup issues a new IP address each time I dial up ( which, of course, I rarely do, but my daughter is Mktng Coordinator for the ISP, so why should I quit them, besides which ATT says I have no dialup if the cable is out).
Anyhow, most ISPs strive for approx an 8-1 ratio, modems to subscribers. If I should disconnect, it's entirely possible for the next dialup to be assigned the same address, as soon as it is freed. If it were a busy time of the day, it may even be likely, as there would be few free. I'm sure most of you have goten busy signals with the old service. ( Listen to me: 3 months cable.)
If you were one of these 3 ( ? ), it's entirely possible you could have gotten the same address.
The only way to always have the same IP address is to register a domain and to use your own server, or to be hosted by others, THAT is static, all others are dynamic.

[Spicuzza]

Sterno,

Thanks for reposting. You are correct I am not understanding web proxy.

I thought all machines had to be uniquely indentified.

Do you mean that the "AOL Web Proxy Server" is being indentified as the IP address for multiple users in a geographical location and each machine within that server is identified only to AOL?

What I'm trying to understand is whether or not you could block a nuisance poster by their IP address. From what your saying it appears that if you blocked IP address 64.12.96.199 that the result would be blocking anyone that comes through that server.

Is that correct or have I missed something?

[sterno]

I thought all machines had to be uniquely indentified.

As a general rule, yes. People's PCs talk to the proxy and say "I want this URL", the proxy talks to your web board so your board only sees that IP, but both the PCs and the proxy have unique IPs.

Do you mean that the "AOL Web Proxy Server" is being indentified as the IP address for multiple users in a geographical location and each machine within that server is identified only to AOL?

Not necessarily, as I recall current AOL users do have their own IP addresses but their default setup uses a caching proxy to try to speed up web browsing.

A caching proxy serves the same general purpose as your web browser's cache, but for multiple machines. The web browser connects to the proxy and says "give me http://www.example.com/", the proxy checks to see if it already has a copy of the page and either returns its copy or connects to www.example.com and gets a copy to return. It doesn't speed things up as much as your browser's cache because you still have to download the pages from the proxy, but if the proxy is close to you (on the network) it can be faster than getting the pages and images from the actual web site. Since AOL has had problems in the past with outside network access being slow, caching proxies are a good idea for them.

What I'm trying to understand is whether or not you could block a nuisance poster by their IP address. From what your saying it appears that if you blocked IP address 64.12.96.199 that the result would be blocking anyone that comes through that server.

That is correct. Proxy servers throw a monkey wrench in to IP-based access control. Your board software would have to know how to handle proxy servers, and the proxy would have to be configured to add the appropriate data to say it's a proxy. Often neither of those is true.

[Spicuzza]

Sterno and all others,

Thanks for the replies.

It's obviously not as straight forward as I thought.

[gmatov]

By the way, would I be wrong in assuming that your assigned IP address for the session would also point to your Network card, which has a "unique" ID of 6 groups of 2 characters? That card ID is related to the assigned IP address, in a similar way as the individual computers are ID'd on your network when you use a second computer in Connection Sharing. All requests to the web go out as coming from the computer that is actually connected, and are rd-directed to the originating computer, under DHCP, which uses addresses like 192.168.1.100, but the adapter address must be as pertinent as the internal IP address.
Actually, since the RIAA is suing Verizon to tell them who is sharing these 600 files, I have to assume they can't tell who XXX.XXX.XXX.XXX is, unless Verizon tells them who was assigned that # at the moment that the files were being transferred.
I said previously that you had a 3 day lease, but never checked to see if the address changed if you disconnected for the night (or day; some of you must keep weird hours. ) I'll write the address down tonight and check if it changes tomorrow when I get home from work and re-connect. If it doesn't, I'll try shutting off my modem next time. Just out of curiousity, of course.

[sterno]

The ID number on the network card is normally written as a set of 6 hexadecimal numbers (hex is base-16, it uses numbers 0-9 and letters a-f). It's called the MAC (Media Access Control) address, and every card in existence has a unique MAC (in theory, anyway). It's a hardware address, it's a little bit like an IP address but it works at a lower level, do a web search for the 7-layer OSI model if you want more information on that. One thing that routing hardware does is associate IPs with MACs, but beyond that they really aren't related to each other. A card sitting on your shelf doesn't have an IP, but it does have a MAC. The MAC is also pretty much hard-coded on the card, many current cards are programmable so you can change the MAC on the fly but as soon as the card resets (like when you reboot) it'll go back to its own.

Windows Internet Connection Sharing is a form of NAT (Network Address Translation), like WinGate in older versions of Windows, IP Masquerading on Linux, etc. Machines on the internal network will have IPs like 192.168.1.x or 10.x.x.x, which are ranges reserved for private internal networks (there's another one, but I don't remember it off the top of my head). If they show up on the internet the packets will just be dropped because those are defined as being non-routable in the open internet. Any machines behind your NAT machine might as well not exist as far as the internet is concerned. All the connections originate from the IP (and MAC) of the NAT gateway, and that machine just keeps track of what outside connections go with what inside machines. That's why some programs either don't work or need a special setting to work on one of the internal machines.

Nobody but Verizon knows who had their IPs at any given time. Depending on how their machines are configured, they may or may not have a record of the MAC associated with the IP. They probably do in the logs for the DHCP server, but it's not guaranteed.

[gmatov]

Sterno,
No luck on the 3 day lease for ATT cable. When I reconnected this PM, I got a new lease, but since I've got a cable router, my IP address is, I guess, now taken by the router, and I haven't been able to see "It" to know what IP is assigned to it. In other words, the IP address leased to me no longer shows in winipcfg,
Each machine is assigned an internal address in the 192.XXX block. Of course, it has to be, as I can access the net with all the machines I have hooked up, 4 at the present time, but more for file transfer. The only time I use another machine for the net is when I screw up and start a convert on this, the machine in front of my recliner, and go to the hard on the ass chair where the other machines are.
I just became a little more confused. I booted another machine to check the IP. This one is .100, that one's .101. That's not confusing, but this one's lease is from 3:38 PM, when I booted, and the lease on that one is 4:40, when I booted it. What am I leasing, an IP from ATT, or am I leasing my internal address from my cable router? Curious.
George

[sterno]

Your gateway box is acting as a DHCP server on your internal network, so machines on the inside will get leases from it that have nothing to do with your provider. You could disconnect the router from your cable/DSL modem and it would still give you internal DHCP addresses. The router gets an external IP for itself from your provider. Most of them have a web interface for configuration that includes a status page with the address information.

[gmatov]

Sterno,
That's basically what I said. my router is assigning my machines an internal IP address, in line withth addresses I had, on my LAN, before I plugged in my router. Now I was under DHCP before, and it seems DHCP still contros, whether from my # 1 machine, or from the router is immaterial to me. I simply can't report whether my cable ISP assigns me a new IP address each time I connect now, as I could before I set up the router.
This too is immaterial. I thought I was going to provide some information, but it's not accessible to me at this time. Mebbe after I dig a little. I don't wanna screw my net up. I've done that too often.
George