I am really surprised that nobody has commented correctly to this post. After working in the catv industry since 1977, and working in the cable modem
department since 1995, I think I know a thing or 2 when it comes to either.
Your computer was connected to your router in your house, and since your computer connects to your router, your computer said all is well. If you are
on a cable modem, your modem may have been down for one reason or another. Such as:
1. Ingress. Cable modems transmit their data from your house back to the cmts (Cable Modem Termination System) anywhere from about 5 mhz (megahertz)
up to 40 mhz (in the USA, anyway, Euro-docsis is different).
For example, if your modem is transmitting at 27mhz, and there is a loose connection somewhere between your modem and the fiber node, and someone on a
cb radio transmits in the general area, there is a GOOD chance that your modem could drop. Most cable companies ignore those frequencies though. but
there are other problems. Anything in the range from 5-40 mhz is in the short wave band, and an open in the cable plant (no shielding) can mean that
your modem could drop offline, even though your computer will tell you that you are still connected. There is A LOT more, but I don't want to get too
technical (unless you want me to.)
2 DHCP servers
In most cases, your dhcp lease lasts for AT LEAST 24 hours. That means that your lease will last for 24 hours, and at half the time of your lease,
you will ask to renew it. That means that you will ask for your ip address 12 hours after you received your last ip address. The server will have to
be down for at least a day for you to notice that.
If you suspect your dhcp server is down, I suggest trying to ping a known ip address, or try this: open a web browser and type this in:
This should take you to google.com
If it does, then your internet is up and your dhcp server is down. Usually very unlikely
Look at the lights on your modem. On our modems (we issue Motorola Surfboards), there are usually 4 lights lit:
downstream lock - if this is blinking, your cable is probably out
upstream lock - could be an ingress problem
online - could be dhcp OR tftp server problems (provisioning)
ethernet connection - no light means no link to your router, bad ethernet cable or something
some modems may have a blue light, and that is ok, that means wideband, which is a good thing!
When it comes to dsl (DinoSaur Link), I don't know much about it, but I could find out if anyone wants to know.
Anyway, there is generally NOT a major outage with the internet, only a localized outage, and as far as my company is concerned, these are priority
calls and get taken care of first.