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If I set up my router to hand out static IP adresses, as far as I know, I will have to configure my computer to use a specific IP adress.

What will happen if someone don't configure their computer, will they be given an IP automatically by the router or will they have to configure their settings to connect?

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up vote 2 down vote accepted

Do you mean to say that you have disabled DHCP on the router? In that case, machines that are not set up to use a static ip will most likely fail. However, if you mean to say that you've assigned specific IP addresses to specific MACs, then DHCP is probably still running, and new computers will be assigned IPs automatically.


It looks like what you are doing is setting up a static IP on the client side (your computer running Windows 7). This will have no effect on the router's ability to hand out new IP addresses to other computers using DHCP (see below). You should have nothing to worry about. You will then need to configure the router itself to forward ports to the computer with the static IP. Check the router list at portforward for your router model for instructions on how to set things up on the router side.

DHCP, by the way, is a protocol whereby new computers connecting to a network are automatically assigned an IP by the router. For more information, wikipedia has an excellent explanation of DHCP.

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As of current it's working fine, i haven't changed anything. I'm a newbie to these kinds of things, i'm not sure what DHCP is. I'm trying to set up a static IP so i can forward some ports and increase the ping for some applications. I'm following this guide: , but it doesn't say anything about configuring the router. The router is currently set to hand out IPs dynamically, do i need to change anything or will that guide work just fine without any changes? – qwerty May 13 '11 at 16:10
I'm editing my answer because the explanation is too long for a comment - see above. – Fopedush May 13 '11 at 16:16
@qwerty you should then update your question - that's an entirely different (and better) question! but try saying also why you want to "increase the ping for some applications". be as straight forward as you can, and you will get better answers. – cregox May 13 '11 at 18:35

There are a few things wrong here and it is hard to explain but I will do my best:

Basically, DHCP is a process running on the router which "dishes out" IP addresses to any machine on the network requiring an address.

Now, Dynamic vs Static, Dynamic is the D in DHCP, in this context it simply means a client of a DHCP server. In this same context, Static simply means not using DHCP and manually configuring the network address.

When you set up a static address (default settings e.g. not setting an alternative), you are instructing your computer NOT to use DHCP.

Now, if you choose an address in the same range as DHCP, it is possible that the DHCP machine will try to give out that same address, in which case, there will be an IP Conflict on the network.

I would recommend that if you can not change the DHCP range, you simply add an exclusion/reservation on the addresses you want so they will not be reused.

... ...

Now for the second part, port forwarding does not matter, or have any difference in DHCP or Static, you simply give it the end address and it will forward to it.

... ...

Now lastly, re reading your question, if you are talking about your ISP giving you multiple IP addresses, this is a much harder and complex situation.

Basically put, a router uses a service called "NAT" which has a one to many system that can forward a port to an IP address connected to the same router. When you disable NAT, you are effectively giving every computer connected to the router their own direct line to the internet and there is no need to set up port forwarding as if a connection come in, it will go straight to them - your router is just directly routing the information.

This can get a lot more complicated and I am unsure to exactly what you need/what you intend to do. Please leave comments and I will be happy to help you further.

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wow, after qwerty's comment on Fodepush's answer, I think you went way too far for him! But +1 for nice answer. :P – cregox May 13 '11 at 18:31
@Cawas ... Yeah! :S Oh well... happy to help! – William Hilsum May 13 '11 at 18:40
Thank you, this was really informational! – qwerty May 14 '11 at 16:34

You're mixing everything up!

You can't set up your router to hand out static IP adresses - static IPs on a LAN are set up on each machine. If not, they're dynamically set by the DHCP, which is usually on the router.

Internet providers Static IPs at other hand are given to you through your modem - and that's not a TCP communication there. It's a whole nother complicated subject.

So, if you want to have static IP on a LAN, just setup each machine to your desired IPs. You can also set up on the router to distribute the IPs based on mac addresses of each machine, which might give the illusion of static IPs, but it's not.

And if you want an internet static IP, you'll have to pay extra bucks for your internet provider for it.

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