Looking for a NIC that works with 2.5Gbps GPON OLT SFP

[Arjestin]

I'd like to throw away my ISP's media converter, and use my home-lab PC as the internet gateway instead. To do so, I'll need a NIC that works with a 2.5G GPON OLT SFP Module.

There is a video on YouTube showing this exact setup, achieved by "Chelsio 110-1146-40 T420-CR T420". I'm sure there are others (maybe better) NICs for a stable 2.5G ISP connection. Hopefully, someone on STH has experience with connecting their ISP's fiber optic cable directly to a home server, and can recommend the right NIC for doing that.

 

[Arjestin]

Can anyone recommend a NIC that supports 2.5Gbps fiber SFP modules, like these ones?

https://www.aliexpress.com/item/1005005928774396.html

https://www.aliexpress.com/item/1005006308599564.html

 

[Muppet17]

The only NIC I know of that can do this are Broadcom BCM57810S based cards.

You will need to use Broadcom's ediag tool to force the port to recognise HSGMII SFP modules, followed by kernel patching whatever firewall solution you decide to use.

Have a read here, I used to run an implementation like this in OPNsense with OrangeFR 2.2G fibre offer. I've since stepped back down to sub 1G world, 10G LAN and >1G WAN is heat intensive and requires more electricity...
[Internet] Bypassing the HH3K up to 2.5Gbps using a BCM57810S NIC - Bell Canada | DSLReports Forums

Side note: I believe you are talking about an ONT module (not OLT). ONT is on the user side, and requires programming with ISP specific info (typically serial number, hardware version, etc) to synchronise with the upstream OLT tree. If you really do have an OLT SFP module, then your circumstances are very different, as this is typically the module on the ISP side that they use to send out to their clients.

 

[Muppet17]

Can anyone recommend a NIC that supports 2.5Gbps fiber SFP modules, like these ones?

https://www.aliexpress.com/item/1005005928774396.html

https://www.aliexpress.com/item/1005006308599564.html

The first one is an XPON ONU stick. You can use this if you have an XPON offer from your ISP. Seeing how you're talking about 2.5G, you could be on GPON, so you would need a GPON ONU. My recommendation is to stay away from aliexpress for these sticks and get a proper programmable one from FS.com or other brands such as Nokia etc.

The second one is an OLT module. I highly doubt you would be using this, these are typically used on the ISP side, not client side. The consequence of plugging the wrong module into your fibre network could be severe - possibly resetting or crashing the connection of everyone else on the fibre tree (your neighbours!).

Please double check your fibre delivery method and protocol, if it is indeed GPON then you also need knowledge of how the PON module will synchronise on the tree. This is the first layer of authentication. The second layer of authentication is the usual PPPoE or DHCP methods we are used to with cable internet. If you have XPON then the methods should also be similar, but this is fairly new territory as not many ISPs worldwide are on XPON or XGSPON yet, and even fewer examples of bypassing the ISP box are available online.

 

[Arjestin]

The first one is an XPON ONU stick. You can use this if you have an XPON offer from your ISP. Seeing how you're talking about 2.5G, you could be on GPON, so you would need a GPON ONU. My recommendation is to stay away from aliexpress for these sticks and get a proper programmable one from FS.com or other brands such as Nokia etc.

The second one is an OLT module. I highly doubt you would be using this, these are typically used on the ISP side, not client side. The consequence of plugging the wrong module into your fibre network could be severe - possibly resetting or crashing the connection of everyone else on the fibre tree (your neighbours!).

Please double check your fibre delivery method and protocol, if it is indeed GPON then you also need knowledge of how the PON module will synchronise on the tree. This is the first layer of authentication. The second layer of authentication is the usual PPPoE or DHCP methods we are used to with cable internet. If you have XPON then the methods should also be similar, but this is fairly new territory as not many ISPs worldwide are on XPON or XGSPON yet, and even fewer examples of bypassing the ISP box are available online.

It is indeed a GPON. Specifically, my ISP provides clients with a NOKIA G-010G-P media converter.

I read an online article, showing how this 2.5G Fiber Optic Media Converter + a GPON ONU can replace my ISP provided media converter, to achieve >1G WAN. And yes, according to this article the process involves programming the GPON with ISP specific info (serial number, hardware version, etc).

My silly idea was to go a step further, and install a low-profile NIC with a 2.5G SFP in a small factor PC (something like this Minisforum MS-01). Then the GPON could be inserted directly to the mini-PC, and I'd have an all-in-one router solution.

 

[Muppet17]

My silly idea was to go a step further, and install a low-profile NIC with a 2.5G SFP in a small factor PC (something like this Minisforum MS-01). Then the GPON could be inserted directly to the mini-PC, and I'd have an all-in-one router solution.

In this case it is the tried and tested method specified in the dslreports link.

1. Buy a BCM57810S based card - other SFP/SFP+ cards will not sync a HSGMII module.
2. Get a SFP HSGMII compatible ONT module. Popular one right now is GPON-ONU-34-20BI from FS.com. You need to know how to reset the serial number on these. There are other alternatives listed here: FS.com GPON ONU Stick with MAC (GPON-ONU-34-20BI)
3. Synchronise your ONT first in 1G mode, you can do this with a cheap media converter such as the TP Link MC220L. You're looking for an "O5" code in the ONT monitoring to indicate it has a place in the OLT tree. This means you can proceed to your ISP authentication.
4. Edit: change your ONT to 2.5G mode. You will be kicked out of admin now and the only way to use the ONT now is in 2.5G mode!
5. Boot your BCM57810S in DOS mode and change one of the ports to 2.5G mode with ediag. Method is in dslreports link
6. Re-check you get O5 at 2.5G
7. Patch your firewall kernel with the hacked bxe driver to allow 2.5G operation
8. Boot your firewall with the BCM card and patched kernel - you will see an uplink (it might show 10G but it is actually 2.5G)
9. Set up your WAN authentication in your firewall per your ISP requirements (PPPoE, DHCP, etc)
10. Do a speedtest at 3am to see your WAN speed maximised

As you are on a GPON tree it means that the 2.5G link is shared with your neighbours (multiple ONTs connecting to 1x OLT), so speed tests will vary throughout the day depending on their bandwidth consumptions.

Good luck!

 

[Arjestin]

As you are on a GPON tree it means that the 2.5G link is shared with your neighbours (multiple ONTs connecting to 1x OLT), so speed tests will vary throughout the day depending on their bandwidth consumptions.

Good luck!

Thanks for summarizing the steps in this procedure.
Looks like it's going to be a journey