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View Full Version : Interesting problem with connection, ip address?, DHCP? help?


whitey102
17-10-2007, 21:52
I have virgin media cable broadband size L (4mb) at home with the standard cable modem which was provided by NTL few years back and a Linksys WRT54G broadband router. All works perfectly have one PC directly connected to router and another PC and a laptop connected wirelessly. DHCP assigns each computer with an ip address 192.168.1.101 etc.

My friend next door has cable broadband size XL (10mb/20mb not sure if it has been upgraded yet or not) he also has the same modem which was provided by NTL few years back and he has a very similar router the Linksys WRT54GS(one with sppedbooster).

The problem first occurred he tried to connect his xbox 360 to his wireless router, It wouldn’t assign an ip address, whereas if he connected to my router he had no problem at all. This was strange I thought because I set up his router and all the settings were the same as mine at home. I then tried to connect my laptop to his router, and the DHCP wouldn’t assign me an ip address, it either gave ‘invalid ip address’ or assigned me a private something address starting with 169.1…… and it would say ‘limited or no connectivity’ – which was no connectivity. We worked out that only one piece of equipment could be connected at once to his router, so the xbox would work if you disabled the network connection on my frinds PC which was connected directly to his router.

The only thing I could think of was that the router was faulty, so I swapped over the two routers and too my surprise my router was now having the same problems connected to his internet connection and his router was working perfectly on mine!!!

It cant be the router as I’ve also tried a netgear WGR614UK as well and also the same problem on my friends connection and no problem on mine!!!

anyone have any ideas what may be the problem with my friends connection??

Anyone experienced the same problem??

fatassmichael
17-10-2007, 21:58
Did you power cycle everything when you plugged in the xbox?
Edit: :welcome: to the forum

whitey102
17-10-2007, 22:07
not sure what you mean but i've connected a few xboxs to routers before and had no problems, it won't connect to my friends connection, won't find ip address if computer is on downstairs

fatassmichael
17-10-2007, 22:10
What i meant was, did you turn off the modem, router and pc/xbox, connect xbox, then power on modem first, wait until the lights have settled, power on router, again wait until lights have settled, then boot pc/xbox.

whitey102
17-10-2007, 22:24
no not tried that, but that does not explain why i can't connect my laptop

fatassmichael
17-10-2007, 22:33
In your friends router config, does it have an option to limit the amount of "dhcp users". I have the same router as you, although i have flashed it with the dd-wrt firmware, so i can not remember the options on the linksys firmware.

Edit: is the xbox connecting through wireless?

MovedGoalPosts
17-10-2007, 22:49
Presumably, being so near to each other, you each use a different wireless channel to reduce interference?

To rule out anything odd with the broadband service, I assume you are able to get an internet connection if a single computer is connected via ethernet to the modem?

whitey102
17-10-2007, 23:00
x box is connected wirelessly

yes it does have the option to limit the users, the linksys routers are both set to 50(defalt)

---------- Post added at 23:00 ---------- Previous post was at 22:52 ----------

yes we use separate wireless channels and i'm positive that it has nothing to do with the problem

yes when you connect single computer through erthnet there is no problem and when you connect the single computer through router also through erthnet it assigns ip address ok as well and works fine. its just when you then try to connect anything else to it at same time

i reckon its got to be something with the modem or connection with virgin

fatassmichael
17-10-2007, 23:03
Has the wireless been secured, and are you using the same security mode, ie, WPA/WPA2?

MovedGoalPosts
17-10-2007, 23:06
I can't see how the VM modem would affect the ability of a router to issue more than one simultaneous connection. What happens if you disconnect the router from the modem, and just have the computer and xbox connected (make sure you reboot everything). Both devices should get a 192.168.x.x type IP address? If they don't, you know it's your router / local network setup and/ or the configuration of the settings on the PC / xbox.

whitey102
17-10-2007, 23:20
I can't see how the VM modem would affect the ability of a router to issue more than one simultaneous connection. What happens if you disconnect the router from the modem, and just have the computer and xbox connected (make sure you reboot everything). Both devices should get a 192.168.x.x type IP address? If they don't, you know it's your router / local network setup and/ or the configuration of the settings on the PC / xbox.

thats exactly what i thought 'how could the VM modem affect the router to issue more than one simultaneous address' but i'm 95% sure thats whats happening, strange i know!!!

The idea of disconnecting modem i have not tried. Great idea didn't think of that. I will try that tomorrow and let you know the result

cheers

---------- Post added at 23:20 ---------- Previous post was at 23:17 ----------

Has the wireless been secured, and are you using the same security mode, ie, WPA/WPA2?

this problem has nothing to do with the security modes, same problem if security is on or off.

Mr.X
17-10-2007, 23:29
169 IP addreses are assigned internally when the device is unable to get an IP address. Either the device isnt requesting an IP address or the router is not assigning one. As Rob says its not definately not your modem.If their was a problem with your modem then you would'nt get a connection on anything.

PaulH225
18-10-2007, 09:32
Something else to check is that there's no MAC filtering on the router. Since you can get an IP address wired the DHCP service is running on the router. So it's most likely to be either a wireless authentication/encryption or MAC filtering issue. I'd suggest maybe trying the wireless with no encryption and no MAC filtering, if that works then add encryption and MAC filtering back in and see if it's fixed.