If you want to connect your Canon IR 5000-6000 printer to your modem, LAN is the only way to connect them, because this series of printers uses only USB or LAN connections.
1. Make a LAN cable that reaches between your printer and modem.
2. Connect each one to the printer and modem's LAN port and it's done.
If you you want to install the printer in your Windows pc's by your modem ( Make sure your pc connected to your modem by wired/wireless) follow this steps-
1. Go to your Windows pc search 'devices and printer'.
2. You will find a program named 'devices and printers' click on it
3. After that program open you will find a tab named 'Ad a printer' click on it.
4. By clicking on 'Ad a printer' tab it will show two options 'Ad a local printer' below 'Ad a network, wireless or Bluetooth printer' click on the below one.
5. Then wait until it searches for wireless and network printers and display the names of available printers.
6. Select your printer from the pop up list it will be automatically install the selected printer wait some moments.
and it's done.