At least four 2.5G ethernet ports, WAN + 3 LAN switched to avoid CPU load.
Passively cooled, metal-case-as-heatsink, very thin/low profile to fit inside wall enclosure.
<10W power consumption while idle, 12V power supply preferred to be able to share power brick with GPON terminal.
As much CPU power as possible for Wireguard tunnels, but again, within idle power constraints.
OpenWRT supported, mainline.
Available in EU.
Don’t really need USB, WiFi, HDMI, power hungry SATA/NVMe, etc.
SQM isn’t needed as well, no buffer bloat problems with my 1Gbit/s up/down fiber.
My five year old Netgear R7800 can NAT at 1Gbit/s line speed with software offload, but can only handle 270Mbit/sec through Wireguard tunnels, consuming around 7W.
Basically I’m looking to upgrade my cat5e cabling to 2.5G and increase Wireguard speed to at least 1Gbit/s, while staying close to existing 7W power consumption.
NanoPI R5S has only two 2.5G ports and from the looks of it uses some kind of OpenWRT fork, instead of upstreaming their code. Pass on that.
Additional 2.5G switch is something I want to avoid, because of more wiring, wasted ports, wasted power etc. ISP provided Alcatel ONT terminal consumes ~7W, waaay too much for a simple fiber-ethernet bridge job.
According to reviews, Aliexpress N6005 and N5105 router boxes screwed up something idle power consumption wise, definitely going over 10W idle.
So far the only option that kind of fits my requirements is older J4125 box. Four ports, 5.5-6W idle consumption, CPU should probably handle gigabit Wireguard. Although some people report RAM compatibility problems, lack of support, well... typical Aliexpress product problems.
I can only say ghat i have the version "even older" based on the c3160. 8GB of memory, 128GB SSD, it just runs and it runs well. Never had any issues.
Runs coreboot bios, but no 2.5Gb/s ports
The typical consumer router is stuck at around 500MBit/s. The ones with HW offloading end at 9xx-something. A few ones are available with 2.5 on the WAN side only.
The lack of available chip manufactoring capacity wont likely change that for another 2-3 years. Evolution is mostly standing still at the moment in the SOHO router market.
2.5 will still be a rare unicorn in the soho market, so even in 3 years no good lookout.
Except business fireall appliances, your best (and prob only option) is to build one yourself with standard x86 consumer parts.
There is a german bulletin board discussing custom-build PCs (some with even less than 10W idle) mostly for home mini servers. You need to handpick parts, mostly not too old intel 2-4 core, a Fujitsu or ASROCK Mainboard and a Pico PSU or Corsair Rmxxx PSU will raise the power savings bar:
(top link in first post is a google spreadsheet with several builds, but a lot of newer systems at the end of the thread are currently missing in the google spreadsheet)
Combine that with a 4-way server NIC PCI-E (which might be a bit expensive, but you’ve asked for 2.5G) and you are in.
I've gone the 'build your own router' before using PC components and at idle used over 100W of power (granted i used 2 10g ethernet cards and each consumed 12w at idle). I switched to an Intel Celeron SBC passively cooled system from Aliexpress. They come with either 4 or 6 intel 2.5G ethernet ports and various Celeron processors from 7th gen to 11th gen. My 6 port Celeron J4125 version runs 12W at idle so I'm sure a 4 port would probably fit within your power budget. Do a search for 4x intel i225. I'd recommend supplying your own ram/storage and not purchasing it with the SBC but if you aren't tech savvy buying it together is simple.
Was attempting to do a similar job myself, get a openwrtx86 build with 2.5Gbps bit more future proofing (as much can).
I skipped the Raspberry stuff due to security concerns mentioned on this thread here
The Celeron J4125, it is perhaps doable but there are some reviews suggesting its lacking that bit of extra power to really do 1gig+ both ways properly, see this review here. It should be noted its perhaps overkill so you may still be fine with the J4125.
These intel i225 and 6 chipsets are not 100% from sounds of things, connection drop outs and other issues so those Ali express boxes are hit and miss. Also tons of hardware issues, but again hit and miss.
I think you sadly need to look at the The other N5105 and N6005 hardware, but sadly you may hit 20-30 under load watts with that and maybe 15-20 watts idle but at least it should do the job and be more future proof.
I will post below some extra bits I hard read to provideperhaps other ways to reduce power comsumption.
There are some other settings that you maybe able to apply to existing PC hardware or openwrtx86 routers though which I need to explore, bios tweaking to reduce power(states) switching off as many ports, sound, gpu, usb, serials. You maybe able to remove the ssds/nvmes, wifi cards, reduce ram modules. Even update to a higher quality power adaptor some guys over on servethehome community mentioned.
And this power states one ( still trying to figure it all out) here
These above appear to reduce power states of the intel cpu, some are also downclocking or capping their cpu cores to say 1ghz or 1.5ghz and saving even more wattage.
I wish I could know the exact commands or options to do within openwrtx86 but am new to it and still trying to read it up, I may post a separate thread asking for direct help on it. If I get any anywhere Ill re-link the thread here or in a post below.