LtAP LTE6 kit

The LtAP LTE6 kit (product code RBLtAP-2HnD&R11e-LTE6) is a router that gets its internet from a SIM card. It belongs where there is no fixed line, or where one is not dependable enough: a site hut, a boat, a camper, a temporary office unit, a roadside cabinet with a camera in it.

The catalogue lists it as an LTE device with the default configuration router-lte. That means the tool proposes lte1 as the WAN interface instead of an ethernet port. Everything you fill in about your internet connection therefore goes over the SIM, not over a cable.

The port and the modem

• lte1: the modem, and your WAN by default. This is where you enter your carrier's APN and, if needed, the credentials that go with it.
• ether1: one gigabit port, with PoE-in. Usually your LAN port, towards a switch or a single device. Because it has PoE-in you can power the box over that same cable, which is convenient on a mast or in a cabinet. See PoE-out per port; this model has no PoE-out.

One wired port is this device's main limitation. Roles that need at least three wired ports, such as Office router with VLANs, Router + CAPsMAN and Hotspot, are blocked with "Needs at least 3 wired ports". For more devices, put a switch behind ether1.

You can also use ether1 as a second uplink instead of as LAN, for instance when a cable happens to be available. See Several uplinks: failover and load balancing. Bear in mind that you are then left with no wired LAN port and everything has to go over Wi-Fi.

Wi-Fi

One radio, wlan1, on 2.4 GHz. No 5 GHz. For this kind of location that is often right: reach matters more than speed, and the line everything passes through is the mobile connection anyway. A wide channel gains you nothing on 2.4 GHz, so pick a narrow one. See Channels, width and power.

The Wi-Fi package for this model is wireless, the older of the two Wi-Fi packages in RouterOS v7. So the configurator writes the wireless side as /interface wireless. The tool reads that from the catalogue record; you do not have to pick it. See Setting up Wi-Fi.

What is inside

From the catalogue: an MMIPS processor and 128 MB of memory. That is comfortable for the role this device gets, and it sits just above the point where the configurator warns about tight memory. The switch chip and the licence level are not recorded for this model, so this page does not quote them.

Setting up the connection

In the LTE / 5G router role the wizard starts at the uplink. There you fill in:

• APN: your carrier's access point name. This is the field that almost everything goes wrong on. A wrong APN looks exactly like a bad signal: a modem that registers and passes no data.
• Authentication: usually none, though some business SIMs want a username and password.
• Default route and the carrier's DNS: normally leave these on.

After that you set up the LAN: an address range and a DHCP server for whatever sits behind the router. See LAN and DHCP. The rest is the ordinary route: DNS, firewall, management access, system.

What it is good at, and where it runs out

Good at: delivering internet where there is no cable, in one box together with a firewall, DHCP and Wi-Fi. It also works as a backup line behind a fixed connection, see Recipe: LTE as a backup line.

Where it runs out:

• One wired port. Without a switch behind it, this is a router for a single cable.
• One 2.4 GHz radio. Enough for a few phones and a laptop, not for a room full of clients.
• Mobile internet is mobile internet. Many carriers hand you an address behind carrier-grade NAT. Port forwarding and inbound VPN connections then do not work, however you set the firewall. An outbound tunnel to a fixed point is the way in. See WireGuard and Tunnels between locations.
• VPN costs processor. Encryption happens in software here.

Which roles fit

• LTE / 5G router: the role this device was made for. It only appears on devices with a modem.
• Home router: if you would rather walk the ordinary router route, for instance to use ether1 as WAN.
• Access point: Wi-Fi behind another router, everything bridged.
• Wireless CPE / point-to-point and Wi-Fi repeater: possible, but with one radio on 2.4 GHz rarely the best choice.
• VPN gateway: as a tunnel endpoint. Note the remark about carrier-grade NAT above: a tunnel that this device builds outwards does work.
• Harden only (baseline): for an LtAP that is already running.

The quickest route to a working configuration

1. Pick One device and search for LtAP.
2. Pick the LTE / 5G router role.
3. Enter your carrier's APN and leave the rest of the uplink on its defaults.
4. Set up the LAN, pick a country and an SSID, set an admin password.
5. Reset the device and paste the script. See Using the script.

Afterwards, check on the device that the modem is there and connected with /interface lte print and /ip address print. If there is no address on lte1, the APN is the first place to look.

What trips people up

• The wrong APN. The most reported fault on any LTE model: plenty of signal, no internet.
• Port forwarding that does not work. Usually carrier-grade NAT at the operator, not your firewall. See Opening a port for what the tool does write, and build an outbound tunnel if you really need to get in.
• Forgetting the power supply. The port has PoE-in; the injector or switch at the other end has to provide it.
• Assuming unlimited data. Turn automatic updates on with a camera behind it and a bundle empties faster than you expect.