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I have a cable modem from Spectrum (Ubee ddw36c) in bridge mode (you have to pay $5/month extra for router mode) so only one port is active which has the internet connection.

I have this connected to my router (Netgear R6700v2) by long cable to another rooom and everything works fine.It's in another location because this is the best location for all other wired devices and for best wifi signal.

I want to connect my network printer (etherne only, no wi-fi) to the network which is located near the cable modem.

I connected a switch to the modem with wired connections out to the router and the printer.

The printer isn't getting the right IP address from the router.

Do I need to have a router near the cable modem and connect the printer to it and then configure the wifi router as an AP and connect it to this router? Is this how I can get my printer connected to my local network.

Right now the printer is getting some IP address that isn't on my LAN. It's 68.175.XXX.XX which seems to be a time warner IP. But it's not the same as my public IP address which is 72.227.XX.XXX which is also a time warner IP.

Is there a way to get my printer on my network without getting another router?

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  • If you can do it through its panel settings (assuming there is a panel), the printer can be given a fixed IP address outside the router's DHCP pool, but within your intranet address range. A fixed IP is recommended for a network printer, and this can be set through address reservation in the DHCP server or by disabling DHCP and setting the address manually, as already described. But I haven't a clue why your printer is picking up an external IP.
    – AFH
    Dec 21, 2017 at 21:38
  • I tried setting up the printer with a static IP within my local network address range. 10.0.0.12 with subnet mask of 255.0.0.0 and the device is still not found on my network.
    – Mike L
    Dec 21, 2017 at 21:48
  • If you want the printer on the same subnet as the other devices, it will need to be connected to the same router. If it needs to be adjacent to the cable modem, you need the router/DHCP server there. An Ethernet router with no WiFi would do the job if the Netgear is in AP mode, so that its own DHCP server is disabled and the Ethernet router handles it, though you may need to acquire a multi-port router with WiFi (at least 2 ports, one for the printer and one for the Netgear link), and disable its WiFi. Apart from the WiFi coverage you could simply swap the Netgear and switch locations.
    – AFH
    Dec 21, 2017 at 23:17
  • move the printer to the router room?
    – anna328p
    Dec 22, 2017 at 5:02

3 Answers 3

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The problem is you split your network in the wrong spot. You put the switch between the modem and the router. Anything in this area will get an IP address from your ISP, not the router.

You will need to run another cable from the router back to where the printer is (and either plug int into the switch, or into the printer directly). Then you will be on the same "internal" network that everything else is on.

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  • unfortunately running another wire from router back to printer or router back to modem is not practical. But I can solve this by having a router + AP set up?
    – Mike L
    Dec 21, 2017 at 21:52
  • You may be able to set up a bridge using a wireless access point that is next to the printer and bridge it to the existing router/AP that is handling DHCP and then use a short Eth cable to plug the printer into the new AP. You need to make sure you get a wireless router than can support it (or is able to be flashed with ddwrt or tomato). Here is a short article that will give you an idea of how it works: cnet.com/how-to/…
    – MaQleod
    Dec 22, 2017 at 0:32
  • Assuming you are not overly worried about speed, you could use a single long ethernet cable, and get a suitable splitter on each end - ie a single cable can be used to deliver 2 x 100 megabit ethernet connection.
    – davidgo
    Dec 22, 2017 at 3:10
  • You could also look at something like Ethernet over the power line adapters. But yes, you should be able to do a wireless bridge as well. @Davidgo's response wouldn't help because you'd be in the same situation you are in now, two devices on the public (ISP) network. Dec 22, 2017 at 13:38
  • @AllenHoward - you are incorrect about my response. You would use 1 of the 2 cables for the LAN and the other for the WAN side.
    – davidgo
    Dec 22, 2017 at 18:19
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With the current setup, you can't get correct IP address since the cable modem's DHCP server is handling IP addresses (which in this case you always get one from your ISP).

The easiest workaround is having the printer directly connected to the router (i.e move the printer to the router room) then you can get correct IP address at the same time still having access to internet connectivity via cable modem. The reason being this time the router's DHCP server is issuing the local IP addresses

If the router has extra ports then this option is a better choice. Alternatively you may have to try bridging as suggested in comments.

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As others have pointed out, the way you have configured the network is putting your printer outside of your local network and directly connected to the internet. This is problematic from many regards, not the least of which is that anyone can hack into your printer and play around with it, potentially without you even knowing it. Putting a router between your internet connection and the printer would help with this security aspect.

You cannot decide what the IP address of your printer is when your cable modem is essentially directly connected to the printer, your cable company decides that. As others have mentioned, this is an automatic feature of the cable modem called DHCP, which assigns addresses as needed and this can and will change over time. You can control your internal network DHCP assignments by settings within your router but unless you pay extra to your cable company you likely cannot get a static IP address from your modem.

I would suggest that if you absolutely cannot run another wire from a point beyond your router to the printer then get a wireless access point and use that to connect it via wifi. With a reasonably secure wifi network this definitely helps from the security standpoint. Other options would be one of the many plug-in type connections, as the printer does not need a huge amount of bandwidth to do its job. Then you will get an IP address on your network (typically 192.168.x.x or 10.x.x.x) and the printer will be behind the firewall in your router and directly connected to your network subnet. From the technical standpoint, your computers on the network will use the switch (layer 2 addressing - using the MAC address instead of IP address) to connect to the printer instead of requiring a router to translate the packet to a different subnet and forward it (layer 3 addressing) and any access to the printer from the outside internet can be controlled by your router and thus potential hackers can be blocked even before they see the printer.

If you set your printer to 10.x.x.x on its control panel then it cannot be addressed at all since your cable modem is connected essentially to the internet and not a local LAN and 10.x.x.x is not able to be routed over the internet. (https://en.wikipedia.org/wiki/Reserved_IP_addresses and https://en.wikipedia.org/wiki/Martian_packet)

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  • You are welcome! At least my Pluralsight subscription is getting used for something. Working on preparing for my CCENT exam.
    – RudyB
    Dec 22, 2017 at 23:37

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