What causes this kind of interruption? Kind of a long story.

Last night around 5:00pm, the Internet was working fine. I went out to the living room to get some food, watch TV. Came back just after 6, 'net was dead. No connection. Windows gave me the "This connection has limited or no connectivity" bubble. I unplug the modem, give it fifteen seconds, plug it back in, and wait. Three lights came on; a working modem should have four, one always flashing (the "PC" light).

I reboot. Nothing. Ten minutes pass, still no connection; no Internet, no e-mail, no FTP, nothing. I call up tech support. They do a test on the modem, try to connect to it, and apparently, it isn't answering the call. They speak to me in idiotese, I open the prompt, and give them the IP info. Yep, invalid IP. Not as invalid as 0.0.0.0, but still invalid at 169.0.0.1 (which I believe is a variation of a local IP address).

They suggest I try another LAN cable, and as the last option, a USB cable. Another LAN didn't work. The USB didn't work either, but that's alright, since I don't want something that caps me at 10MBPS (LAN cable gives up to 100MBPS, although I doubt a website in existence lets you download remotely close to that rate).

I call them up again, they book a service call for today between 2:00pm and 5:00pm (hey, a lot better than 8:00am to 6:00pm!).

I got on the computer maybe ten minutes ago to do some work, and lo and behold, there is a message telling me I have e-mail waiting to be read. Now, I know you can't check for new mail unless there is a connection, so I click on FireFox and voila, Google pops up. I look down at the modem; same three lights, signaling a faulty modem.

Now, for all I know, the modem could be faulty. I may be connected, but am I connected at full peak? I'm downloading at which I usually download at, but is it going to be consistent? I don't know. So as it stands, the service call is still booked, and the technician should be here between now and 5:00pm. I may as well let him look at it, see why the modem isn't answering any calls from home.



Anyway, what causes this kind of interruption? I mean, why would a seemingly faulty modem let me connect to the Internet, at what appears to be full service, without answering any tests from the company? And why did the modem respond to tests when it wouldn't let me connect to the Internet?

And most importantly, and this is the kicker, why am I connected to the Internet when ipconfig is showing me an IP address of 0.0.0.1 with a DNS of 255.0.0.1 "

 

It does sound like the modem could be faulty. Asking why a faulty item behaves in a faulty manner is a little like asking why white is white. I think the faulty modem may be acting strangely because it is faulty.

If it was me, I'd write off "last night" off as a glitch. If your modem works from now on and you get no further problems leave it as it is.

If you start getting problems the first thing to try is:

tracert 66.249.93.147

If that gets an error straight away, I'd be suspicious of the modem. If you get some replies and then the trace halts, it is likely to be an ISP fault.

Are you still connected via USB? If so the settings on your Network Card will be irrelevant. ipconfig, shows your Network card settings and not necessarily the modem IP set up.

 

No, I wasn't connected via USB, just the LAN cable.

What I did was disconnect the USB and reconnect the Cat5. ipconfig showed an IP of all zero's. Rebooted the modem and PC. When Windows loaded, I tried FireFox, and it connected. I then checked ipconfig, and it showed that 0.0.0.1 and 255.0.0.1.

 

Are you sure 255.0.0.1 is DNS server's address ?

 

Yep. I copied everything ipconfig showed me into a text file in case the technician wanted it, and here's what it said:

Host Name: ___
IP Routing Enabled: No
WINS Proxy Enabled: No
DNS Suffix Search List: ___
Connection-specific DNS Suffix: ___
Description: nVidia nForce Networking Controller
Physical Address: ___
Dhcp Enabled: Yes
Autoconfiguration Enabled: Yes
IP Address: 0.0.0.1
Subnet Mask: 255.0.0.1
Default Gateway: 0.0.0.3
DNS Servers: 255.0.0.1
255.0.0.2

 

It is extremely weird, subnet mask and dns server have the same number even if we ignore some rules.

 

But that wouldn't even be valid addresses for a network connection, would it? I mean, 0.0.0.1 as an IP definitely isn't valid, just as 127.0.0.1 (or whatever it is) is only valid as a local connection. I've never heard of anyone being able to browse online, check e-mail, or download stuff with an IP of the above.

 

What did the technician find?

 

Absolutely nothing.

He chalked it up to a hiccup, and pretty much said the two people I spoke with must not have been performing the connection test right, as everything seemed to work fine. So, he plugged his laptop into the modem, tried to call it, and voila, nothing, no response. He unplugs it, puts it back into the computer, and there he is, using YouTube as a test site.

Ten minutes later, he's gone.



Since then, it has been working fine. No slow downs, no hiccups, nothing. I guess it was just having one of those moments. However, even though everything is fine, ipconfig is still showing weird info. Specifically, the same DNS addresses as above.

 

You did not mention your modem's model and maker, did you?

I GUESS you modem is a combination of modem and router. Why did the technician get nothing, maybe because your "modem" did not allow his laptop's MAC address.

Please confirm what I guess.

 

It's a Scientific Atlantic cable modem. As far as I know, and as far as I'm understanding the documentation, it isn't a combination; just a modem.

 

What's the model? I know DPR2320 has DHCP server inside.
If you have that, please just follow the documentation to re-setup it.

 

If you have XP and Service Pack 2 installed:

Start, Run, CMD

netsh winsock reset

Wait for a prompt that a restart is required. Restart your computer.


If you do not have XP with Service Pack 2 installed, use WinsockFix by Option^Explicit. This will work on Win9x, ME, Win2k, and XP up to but not including Service Pack 2: http://www.tacktech.com/display.cfm?ttid=257


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