Connecting (wireless) router to modem (with integrated router)

Question

I'm trying to figure something out that I think should be possible, but I don't think I have the exact technical knowledge to make it work.

I'm using a modem provided by my cable company that also functions as a wireless router. It has four ethernet ports in the back, but doesn't have the separate port (labeled "Internet" on my router) like other cable modems I've had in the past. They gave it to me when I upgraded my internet speed, and I unplugged my router and put in in the closet as a result.

I pulled my router out this morning because I've just not been getting the quality of wireless that I was hoping for with the upgrade. I connected the modem(w/integrated router) to a cable coming directly from the wall (instead of using a splitter for cable and modem connection), but doing this required me to put the modem into a different room than my living room.

I ran an ethernet cable out to my living room from the room where the modem is now located- my plan is to try to connect that ethernet cable to my router. It's the D-Link 4500. I have connected the ethernet cable to the port labeled "Internet" and have a laptop (wireless turned off for the moment) connected to another ethernet cable going to one of the four LAN ports.

While I can pull up the default IP address for the router, I can't seem to do things like connect to Dropbox or iChat. This makes me believe that there are additional settings within the router interface that I need to change.

I pulled up the user manual for the modem, and it indicates that a hub could be connected to one of the four ethernet ports if one needed to connect more (wired) devices, so it would seem it is possible, somehow- even if just not possible with my router. However after reading about the the differences between an access point, router, and bridge, it would seem that they share similar capabilities so it should be doable.

Thinking about the things I have to change when I'm connecting a new computer at my office, I have to set things manually like the subnet mask, primary and secondary WINS, etc. Does this same idea apply here?

Edit to Add: Changing the IP address on the router interface worked. I'm able to connect to this second wireless network in the same room with 100% connection instead of the previous connection (ps3 was indicating it was about 70%).

I'm going to have to read more about the technical aspects of how this works (or doesn't) because I would like to gain more understanding on this subject matter as a whole.

Thank you @user555 and @Keltari for your input!

Answer 1

Connecting a router behind another one is almost never a good idea, as you might have discovered. If you insist on keeping the ISP provided router/modem combo you will have to put the modem into bridge mode (effectively disabling such things as NAT, DCHP, firewall etc.). In this mode all traffic will pass-through the modem without any modification.

Answer 2

It sounds to me that the modem they gave you is a modem/router/wireless combo. The fact that there is no dedicated Internet port reaffirms that to me.

Now you say you are not getting good wireless signal. Now you say you have your previous router with WiFi, however I am a fan of KISS (Keep It Simple, Stupid). Adding your WiFi router to the network is a very doable, however it does not fall into the KISS solution. For someone without technical knowledge, I would suggest at least trying replacing the antenna on your poorly performing modem with a high gain antenna. Something like this. You can get them from RadioShack, Best Buy, or any computer store. They range in price from around $20 to a lot more. You dont really need the expensive ones. I bought a cheap one and it works great. And hey, if the antenna works, you can sell your old router on Craigslist for more money than you paid for the antenna.

Now, if you really want to use your old router, you can. You will have to read your user manual for it and most likely disable all its services, like DHCP, except for the WiFi. Then you should be able to plug it into any port on the modem. As you can see, there is more work involved in setting this up, as well as adding another layer of complexity in your network. But it will work.

PS. I just checked your old router is 802.11n so it does support the current fastest wireless speeds. You should check if your new modem is N also. If it does, I would just but an antenna. Worst case, you return it to the store.

Answer 3

You need to bridge one or the other, otherwise you get a double NAT and a host of routing problems. Bridge the second router and connect the two via the LAN connections on each device.