Assigning Static IP addresses

bigrich1976 · 27-10-2006, 09:52

Hi,

I was wondering if somebody could help me, i have four pc's on a wireless networks. secuirty is provided by mac address filtering and i want to assign static ip's to each pc. i have rules set up for port forwarding designated to specific ip addresses but i keep getting different ip addresses.

am i right in thinking to do this i would need to disable DHCP in the router config page. and then on each pc right click the network card i use and specify the IP address i want along with subnet mask and default gateway being the router ip address?

Cheers.
Rich

Graham M · 27-10-2006, 09:58

You don't have to disable the DHCP server at all (its useful for roaming PCs - like your friends laptops etc) - just make the range higher, but you're right about the rest.

Stuart · 27-10-2006, 09:59

That would be one way of doing it.

Aragorn · 27-10-2006, 10:12

Don't forget, if you're using a static IP address you need to specify the DNS servers on each client.

ecksmen · 27-10-2006, 17:10

Quote:

Originally Posted by Zeph

You don't have to disable the DHCP server at all (its useful for roaming PCs - like your friends laptops etc) - just make the range higher, but you're right about the rest.

On the otherhand, wouldn't it serve as an extra step if it's disabled in locking down the network?

Bula Bula · 27-10-2006, 17:33

you should be able assign permanent ip addresses via the router, pairing mac addresses with permanent addresses. What 's the router?

janipewter · 27-10-2006, 20:24

If you mean static DHCP yes he could do that, but it would be easier just to set it in the network card properties..

Druchii · 27-10-2006, 20:54

Quote:

Originally Posted by Aragorn

Don't forget, if you're using a static IP address you need to specify the DNS servers on each client.

I just tell my PC's the router is the DNS server. Works fine for me

Graham M · 27-10-2006, 21:06

Quote:

Originally Posted by ecksmen

On the otherhand, wouldn't it serve as an extra step if it's disabled in locking down the network?

No not really, its an extra precaution, but I imagine if they've managed to break your encryption, they'll be clever enough to try IPs until it works if they're really that desperate to get in.

bigrich1976 · 27-10-2006, 22:22

Hi all,

All working ok, I have left DHCP enabled and set the dns as the router ip address and it seems to work ok.

security is provided by mac address list in my linksys router, is that ok? would it be easy to break. to be fair i live in a sleepy village so not overly worried abt security and neither are my neighbours judging by the amount of unsecured networks around

Aragorn · 27-10-2006, 22:29

MAC address filtering is pretty easy to break if you want to.
I would recommend you use WPA encyption if the router/cards support it.

Luappy13 · 07-11-2006, 09:44

Quote:

Originally Posted by bigrich1976

Hi,

I was wondering if somebody could help me, i have four pc's on a wireless networks. secuirty is provided by mac address filtering and i want to assign static ip's to each pc. i have rules set up for port forwarding designated to specific ip addresses but i keep getting different ip addresses.

am i right in thinking to do this i would need to disable DHCP in the router config page. and then on each pc right click the network card i use and specify the IP address i want along with subnet mask and default gateway being the router ip address?

Cheers.
Rich

In answer to the question of how to create a static ip (because I couldnt see anyone answer this):

On each pc requiring a static address:

start > control panel > network connections > right click the connection the pc uses, select properties > General tab > theres an adapter icon with a configure button (click it) > then advanced tab of new properties page and look down the list of properties for one like "Network Address" (click on it and fill in the dotted quad i.e 10.0.0.1 in the value box)

This is useful when hosting a particular service from a particular machine (like a http server) so you do not have to expose all the pcs on your network to port 80 or w/e

---------- Post added at 09:38 ---------- Previous post was at 09:34 ----------

Quote:

Originally Posted by Aragorn

MAC address filtering is pretty easy to break if you want to.
I would recommend you use WPA encyption if the router/cards support it.

MAC Address filtering easy to break - any links to this? or proof of concept on methodology? I think your talking about MAC address spoofing (not hard) but the main part is getting the correct MAC to begin with. If your behind a Hardware firewall you should not be able to do this so please tell.

and WPA is for Wireless data encryption? not quite the same as the question asked and not to be confused as anything to do with static ip adressing.

---------- Post added at 09:44 ---------- Previous post was at 09:38 ----------

Quote:

Originally Posted by bigrich1976

Hi all,

All working ok, I have left DHCP enabled and set the dns as the router ip address and it seems to work ok.

security is provided by mac address list in my linksys router, is that ok? would it be easy to break. to be fair i live in a sleepy village so not overly worried abt security and neither are my neighbours judging by the amount of unsecured networks around

DHCP should be on and thats what takes care of the handing out of IPS to each connected machine BUT DNS should be the IP of your ISP DNS server (assuming you dont have a dns server set up in your LAN^^)

Gareth · 07-11-2006, 10:39

Quote:

Originally Posted by Luappy13

MAC Address filtering easy to break - any links to this? or proof of concept on methodology? I think your talking about MAC address spoofing (not hard) but the main part is getting the correct MAC to begin with. If your behind a Hardware firewall you should not be able to do this so please tell.

You can obtain MAC addresses from clients connecting to wireless access points using Kismet/KisMAC or Netstumbler.

Luappy13 · 07-11-2006, 11:09

Oh okay - heard of aircrack and a few others but didnt think they would sniff mac of the air. interesting... Wireless adapter and a download or 2 coming up

Gareth · 07-11-2006, 11:25

Well, aircrack is really for cracking encryption - airodump is useful for grabbing traffic, and will allow you to capture MAC addresses like Kismet does (look under the station field for MAC addresses of clients, whereas the BSSID gives the MAC address of an access point).

Just out of interest, are you doing this on a Windows box, or under *nix?