Need modem help

This one has me stumped.

My current setup is the small 2 port Ilox modem with a 100' cat5 cable to another modem and then another 100' cat5 cable from that modem to a third modem, all running from one of the Ilox ethernet ports. This all works fine.

I want to improve my wifi range from the Ilox modem and have additional ethernet ports so I got another linksys modem and a 3' cat5 cable to plug into the second ethernet port on the Ilox modem. This fourth modem shows the internet light but won't connect to the internet when plugged into the second Ilox ethernet port. I have tried both ports, different cables, resetting, etc. to no avail. The strange part is if I take this 4th modem and plug it into the ethernet port on the second or third modem it works fine.

Thoughts anyone?

If you have wireless configured on the new linksys you might have a Spanning Tree loop. If - and it's a big if - one of the other devices has been selected to be root of the tree, the port on the Ilox device could be disabled. The problem could be Spanning Tree Protocol preventing a layer 2 loop. If STP is configurable on the Ilox box, set it as root of the tree. To test if SPT is the problem, disconnect your pre-existng devices from the Ilox; the new equipment should start to connect (spanning tree can take up to a minute to right itself). It sounds like you are trying to create a mesh network with your wireless devices. This usually requires compatible equipment from one vendor, however, it's been a while since I've paid any attention to the SOHO market and really don't have a clue as to what's available these day. Good luck.

Modem or router? Probably router. Some routers need to be "bridged"; they won't take a straight through Internet signal like that. Some need a "crossover cable". Linksys is pretty good with their online documentation and support.

The linksys router worked when I plugged in into one of the slaves ethernet ports just not when I plug it into the ILox modem.

Ah, but did you not say all modems are plugged into the iLox modem?

iLox uses a "static" IP address which has an adverse affect on a lot of things, like IPTV, extenders, etc. (Ironically, if you want a static IP from TelMex, you have to pay business prices, much higher.) But an email to iLox will get them to immediately switch you to a public IP. Then, it should work.

Bob, connect your Linksys to Lan 1 on the Ilox modem, then connect your Casita to Linksys Lan1.

That's right! I forgot, an unwritten bit of info on those iLox boxes is that that Lan 1 is a throughput and also a higher-speed ethernet connection.