I have been having a problem where my internet is fully connected as it should be, an IP address is assigned by DHCP, and I am having no problem receiving packets. The problem with this however is that it will not send packets. This used to be a minor issue but now it seems like this will happen all the time and can sometime even last for days. I have tried connecting with both my PC and my laptop and also using different cable connections so I am fairly certain the problem lies with the actual modem or maybe the actual ethernet cable. Whenever i have the problem, neither the Sent or the Sync lights will be one.

Does anybody have any adive or experience with such a problem?1.  Modem.  Is this Cable or DSL connection?

Have you tried to power "reset" the modem?  Unplug it, let it set for a minute, plug it back in, wait for it to initialize.

2.  Weather.  Have you noticed any correlation between symptoms and the weather?  Is it wet or damp when the problem appears?If this is a cable connection that delivers both cable TV and hi-speed internet you need to pay attention to the in-house configuration of your cables.  My guess is the signal quality to your modem is marginal (low or bad).

Where the cable enters the house you normally would install a splitter (probably two-way splitter); one output feeds all of your cable TVs, the second output feeds only the cable modem.  You should never have more than one splitter between your cable modem and the cable entry into your home (because of signal loss).  The splitter should have the proper electrical characteristics (Radio Shack or computer store should have correct ones).

Minimize the coaxial cable length from the splitter to the cable modem.  Instead of locating the cable modem next to your home router and running a long coaxial cable back to the splitter, try locating the modem at the splitter and running a long ethernet cable to the router.  The closer the modem is to the cable entry point, the less signal loss.

You should use shielded coaxial cables of the correct length to minimize the amount of noise you pick up.  You should ENSURE the coaxial cable connectors are tight and secure.  Don't install your own connectors.  Buy cables of the appropriate length with the connectors molded on.  You should disconnect any unused cables at the splitter and place a terminator cap on the unused output port.

You may add additional splitters on the TV side of your configuration if needed but terminate any unused ports.

Until your modem powers up, initializes, and goes online you'll never be able to access the internet.You could always call your ISP provider and have them check their lines (and possibly your inside wiring).

Someone suggested it was the installer's responsibility to ensure a good connection.  The following quote is my RESPONSE to them and sums up the experience which led to the advice I gave in the previous reply.

Quote

Installers?  What installers?  I opted for the free installation (self-install kit).  Everything worked great for about six months.  Then my internet connection started giving me fits.  Some days I couldn't get on at all.  Some days I could work for one or two hours but it would randomly quit working.  The Motorola SB5100 surfboard cable modem would not stay online.  Usually the "send" light would just blink for hours.

So...  Did I have a bad modem or was the signal quality to/from the modem too low?

Called the cable company.  They sent someone out.  He wanted to check the inside configuration first because that's where the problem usually lies.  Customer pays for inside wiring/configuration problems.  I of course wanted him to check the OUTSIDE configuration first.  They pay for delivery problems to the home.  So we had a standoff.  But he was a very nice GUY.  I asked a couple of questions and he basically told me you never split the feed to the modem more than once, pay attention to your cable LENGTHS and connections, and terminate any open connection ports.  He returned to his world and I went to work on my configuration.

I had two splitters between the modem and the cable entry to the home, a long coxaxial feed from first splitter to second splitter in feed to modem upstairs, unconnected cables, and open ports on my splitters.  Wet weather may also be an issue with their connection on my outside wall (not sure about this yet).

So basically I didn't do a good job with the self-install.  I'm still wondering however whether their infrastructure changes dropped the signal quality to my home.

It works well now.