Icotera i4882 is a typically crippled and locked-down borderline useless WIFI AP/gateway/switch which is rented out (not sold) by European broadband providers. It is, on paper, a really good and advanced piece of technology. It is, in practice, barely better than a brick because the firmware end-users get with models delivered by broadband providers such as Telenor is both utterly crippled and completely locked down.
The Icotera i4882 has four antennas for the 2.4 GHz band and eight additional antennas for 5 GHz. It is N, AC and AX capable (as well as older standards).
The locked-down firmware you typically get from broadband providers will not allow you to configure anything beyond the SSID. All other fields are grayed out in the interface. You can make the fields editable in the web interface either by changing the JS file with an override or by changing the HTML - but that's a pointless exercise because new frequency settings aren't saved or used even if you make it possible to change them in the interface.
The "AUTO" frequency mode (which is the only one you can use) will probably pick the absolute worst possible 2.4 GHz frequency and the second worst possible 5 GHz frequency.
HOWTO use the Telenor Icotera i4882 variant as a pure switch/WIFI AP
Telenor has just about every feature the original Icotera i4882 firmware has from the firmware they ship. This makes the Telenor i4882 useless as a home Internet gateway. The actual WIFI hardware in this router is quite capable, so it may be a good fit as a pure access point.
You will want to disable the DHCP server if you want to use this brick as an access point. There is no obvious way to do this in the web interface because that would be allowing you some degree of control of the hardware you have in your own home.
The trick you need to use to disable the DHCP server is to set a DHCP range mismatching the LAN IP you ask the Telenor Icotera i4882 variant to use. If your home network uses 192.168.1.0/24 then 192.168.250.100-192.168.250.200 would be out of range & a good choice. Configure the LAN IP to a static IP on your existing network (like 192.168.1.250) and set the DHCP range to 192.168.250.100-192.168.250.200. The routers DHCP will try to bind to an interface with an IP on 192.168.250.0/24 upon startup and fail - causing it to crash and go away. This isn't a very clean way to disable this routers DHCP server, but it works just fine & it is a "quick fix" you can use if you already have a DHCP server and you just want this piece of junk to act as a pure switch & access point.
Set the WAN interface to use a static IP on a network range you'll never use & put a piece of tape over the WAN port. There is no way to make the WAN port a part of normal switch functionality. This leaves you with two 1 GB ports and one 2.5 GB port as well as N/AC/AX wifi.
Price and Availability
These routers aren't sold in normal stores - or anywhere else for that matter. They are only rented out from ISPs who expect you to return them. Many people don't return them so may be able to find one in a used goods store. We got ours for 150 SEK, which is about $15. That's a fair price. Telenor would like you to pay about 700 SEK for the privilege of renting a crippled Icotera i4882 from them (and they expect you to return it if you stop being a broadband customer). That would be a complete waste of money, you would be much better off spending 700 SEK on a configurable and usable router on sale or 80 SEK (about $8) on something like the 2x2 AC capable Netgear R6220 in a thrift store.