Static IP vs Dynamic IP What is the difference?

A

audiobahn1000

Member
What is the difference between a static and dynamic IP address? I thought a static IP address is one that never changes and a dynamic IP address is one that always changes every time you log into the net. But someone told me that that is not true.
 
yes thats true. static is the same while dynamic it changes. and i think dynamic is when your computer request for an ip and your ISP will give you a new one each time.
 
Well you could be thinking of two situations, but either one is the same concept.

You could be dealing with an ISP - your internet provider.

You could have a static ip service, which is something you'd sign up for. In this case, your IP would never change if you don't change it. It could be something like 72.211.219.41 (random).

You could also have a regular connection like cable/DSL. In this case, your IP wouldn't change every time you connect, but could change on you at any time...in my case, every few months. Ill have the same IP for about 3 months and suddenly it will change.

You could be dealing with a router

In this case, you can tell your router to use DHCP which assigns an ip from the router...something like 192.168.1.100. But, if you're using a dynamic ip, (DHCP) then if another computer is on, you could be bumped to 192.168.1.101.

You might also use a static ip with your router. This would force the router to assign you an ip adress of something of your chosing (within the routers range; could be 192.168.1.100 to 192.168.1.255)
For example, you could assign every computer in your house a specific ip of 192.168.xxx and that wont change.

In both of these Router cases, you will still of course have your ISP's ip address. (72.211.219.41) and your computers local address would be (192.168.1.xxx)

Hope this clears it up.:)
 
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davidireland said:
Well you could be thinking of two situations, but either one is the same concept.

You could be dealing with an ISP - your internet provider.

You could have a static ip service, which is something you'd sign up for. In this case, your IP would never change if you don't change it. It could be something like 72.211.219.41 (random).

You could also have a regular connection like cable/DSL. In this case, your IP wouldn't change every time you connect, but could change on you at any time...in my case, every few months. Ill have the same IP for about 3 months and suddenly it will change.

You could be dealing with a router

In this case, you can tell your router to use DHCP which assigns an ip from the router...something like 192.168.1.100. But, if you're using a dynamic ip, (DHCP) then if another computer is on, you could be bumped to 192.168.1.101.

You might also use a static ip with your router. This would force the router to assign you an ip adress of something of your chosing (within the routers range; could be 192.168.1.100 to 192.168.1.255)
For example, you could assign every computer in your house a specific ip of 192.168.xxx and that wont change.

In both of these Router cases, you will still of course have your ISP's ip address. (72.211.219.41) and your computers local address would be (192.168.1.xxx)

Hope this clears it up.:)
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Well my ISP charges for a static IP address. Why would anyone not what their IP address to change? If anything I think they would charge for a dynamic IP address? Its like chargeing you to have your name appear on caller ID. They dont do that. They charge to have your name NOT appear on caller ID.
 
I'm on DHCP, but it only changes about once a month.

A good work around for a constantly changing DHCP service is the use of DDNS. There's free DNS services at places such as dyndns.com. Most routers will have support for DDNS and update your DNS every time your IP changes. It's almost as if you have a static IP :) . Tis' very useful when you're serving.
 
audiobahn1000 said:
Well my ISP charges for a static IP address. Why would anyone not what their IP address to change? If anything I think they would charge for a dynamic IP address? Its like chargeing you to have your name appear on caller ID. They dont do that. They charge to have your name NOT appear on caller ID.
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Because having a single ip is so much easier if you have a server or do alot things that require a static IP
 
Well if a normal IP address changes everytime you restart your cable modem then how is it that a website forum can ban you and it can reconise you if your IP address changes everytime you restart the modem? I run a forum and I am trying to figure it out.
 
audiobahn1000 said:
Well if a normal IP address changes everytime you restart your cable modem then how is it that a website forum can ban you and it can reconise you if your IP address changes everytime you restart the modem? I run a forum and I am trying to figure it out.
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As far as i know, forums can only ban user accounts and IP's. They cant track you to see what new IP your given.

And having the same IP address is very useful, especially if you have a home server setup.


-Geoff
 
[-0MEGA-] said:
As far as i know, forums can only ban user accounts and IP's. They cant track you to see what new IP your given.

And having the same IP address is very useful, especially if you have a home server setup.


-Geoff
Click to expand...

So then in essence if you had a dynamic IP address you could never be banned from a forum and you could just keep making new accounts? That would be unfortunate for forum admins.
 
Well there are other ways that admins can ban you, there is a little more info they can get. It is not *given to them, but is is very attainable.

I assume they can also ban with this information, and if they can't... they should be able to.
 
I'm positive you can't get banned permanetly from a forum if you have a dynamic IP address, however admin's can ban your e-mail address so you can't register with it again, then you need a bunch of new e-mail addresses which are really easy to get if you want to spam some forum (I don't suggest that).
 
Having a dynamic IP does not mean it will change every time you log on. Your ISP will usually give you a lease on one IP and you will have that one until the lease expires and the ISP issues you with a new IP. This new IP could be the same IP that you have had for the last several years with a new lease for several more months or years. Sometimes it will change when the ISP issues you a new IP. My IP has not changed for the last three years and it is issued dynamically.
 
audiobahn1000 said:
Well if a normal IP address changes everytime you restart your cable modem then how is it that a website forum can ban you and it can reconise you if your IP address changes everytime you restart the modem? I run a forum and I am trying to figure it out.
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A website cannot ban an idividual by their ip address alone. What this forum does (and I suggest you do NOT follow in their footsteps), is ban the whole network that the rogue's ISP has available. This ensures that any address that the individual is likely to get, in the future will also be banned.

This action, naturally, ends up banning thousands of innocent users as well as the one rougue individual. Hence my situation where my own IP Address has been banned by this forum (despite the fact that I have, at no time, entered into any activity to justify such a sanction).

If you want to take the responsible route, this is how the rest us deal with the situation. Once you have spotted activity that you are unhappy about, you take the IP address and feed it into a Whois search. Here's one that works You will then be given details of the ISP responsible for that specific address. Looking down a little further you will probably also find contact details to report abuse. Your next course of action is to report the offensive activity, along with the IP Address of the originator, and the date and time of the offence.

The ISP can then look up their records and find out, which of their members had that precise address at the time of the offence. If this is a first offence of a fairly minor nature, they will likely just give a warning to their member that their activity is in breach of their contract and if this happens again their connection to the internet will be withdrawn.

The fact that they have been traced, is normally quite a shock to the perpetrator and is usually enough to stop them re-committing. Since other website administrators will also be doing the same thing, it is quite possible that your report could be enough to tip the balance to get this nuisance disconected. It is also possible that, what you see as a first offence, the ISP will see as a repeated offence (as they know the background of the user in question, despite their various IP Address changes).

It pays to go through the appropriate channels. I have been responsible for the security of some seriously large networks (upwards of 4,500 computers across 250 sites), so have been on the other side (ie having to trace one of my users, based on complaints from outside the organisation).

In one particular case I was contacted by the police, due to some very disturbing activity. I then tracked down the individual concerned and the specific machine that they had used for their distasteful behaviour. Once the machine had been handed over, they police were able to retrieve sufficient evidence to put this man behind bars for over two years.

Like I say, this is the process that most responsible website administrators follow. The LAZY ones, (such as those that run this site), just ban every address that the rogues ISP has available. The only reason I am still able to post, is that I use a proxy server when conneting to this forum.

As soon as I exit the site, I just turn it off and resume browsing the internet with my own IP address.
 
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