TFTTH-GPON-via-SFP-Module

Modem Selection

First, you need to get a compatible modem that supports both GPON and the SFP format (SFP+ is also fine). My advice is to buy the fiber modem intended for business customers -> Digitalisierungsbox Glasfasermodem. At the time of writing this summary, it costs 40€ net (VAT and shipping not included, so roughly 60€ including shipping+taxes).

Contract Data

PLOAM/SLID/Installationskennung

Tip

That is not needed on newer >=2024 contracts. You can directly ask the telekom-hotline for reprovision Reprovision section.

The next step is to get some data related to your contract, since "Newer than FTTH 1.7=FTTH GGS" the Installation Password (PLOAM) is not needed anymore.
If you still need it, ask for the PLOAM/Installationskennung in German. If you're not sure if you're GGS or still on 1.7, check the remarks in the Telekom Forum

PPPoE Connection

Tip

That is not needed, when easy login is activated

You might also need some details for the dial-in/PPPoE connection which you should be able to retrieve from the customer portal.

Dummy data:

• Access Number: TTTTTTTTTT
• Password: PPPPPPPP
• Line-ID: AAAAAAAAAAA
• Co-User-Number: MMMM (typically 0001)

The PPPoE will be generated from these numbers:

username: AAAAAAAAAAATTTTTTTTTTMMMM@t-online.de  -> Line-ID+Access Number+Co-User-Number@t-online.de
password: PPPPPPPP -> you'll have to enter yours

SFP Modem Configuration

Caution

Only needed when you want to modifiy:

• PLOAM/SLID/Installationskennung
• link speed
• serial number

Set an IP within the subnet for the configuration of the SFP+ Module or ONT.
Service IP for the Sercomm Modems is 192.168.100.1/24
If you use Zyxel / PMG3000-D20B it is 10.10.1.1/24

If using an UDM-Pro it can be done via SSH or GUI, for SSH just do the following:

# UDM Pro Interface Config (WAN2/SFP with PMG3000-D20B)
ifconfig eth9:2 10.10.1.2 netmask 255.255.255.0 up
# verify
ping 10.10.1.1
ping 10.10.1.2

Now you should be able to connect to the service page to enter the Installation Password.

Sercomm

The URL for Sercomm is: http://192.168.100.1/service.html Enter the desired PLOAM and hit “save”.

Zyxel

The URL for Zyxel PMG3000-D20B is: http://10.10.1.1

Default passwords

Sercomm and some Zyxel (e.g. SSH) Modems
Username: admin
Password: admin
CLI-Mode and some Zyxel GUIs:
Username: admin
Password: 1234

SSH Config

In case you want to change things, that might be done via SSH. I found some of those steps in xvzf's repo or other GPON related forums. Requirement is an IP of the WAN or SFP-Interface within 10.10.1.1/24. But not the IP Itself. :) SSH into the module (admin/admin)

admin@10.10.1.1
# in case you got ssh errors:
ssh -v -o HostKeyAlgorithms=+ssh-rsa admin@10.10.1.1
# Login via CLI: admin/1234

Change serial

The first option is not permanent/will be reverted:

sn serialnumber

Thats permanent / reboot-safe:

sn set serialnumber

serialnumber could be anything,
like

• SCOM00012345 -> Sercomm
• ZYWNA1234567 -> Zyxel

It's useful in case you want to have multiple valid SFPs and/or ONTs for testing. More information on the Vendor prefix at.: hack-gpon.org

Troubleshooting

If the serialnumber was already accepted, you can check the status via "onu ploamsg":

admin@SFP:~# onu ploamsg
errorcode=0 curr_state=5

• O1 Initial: the OLT sends a message to the ONU to start the ONU, and the ONU enters the standby state;
• O2 Standby: After receiving the message, the ONU extracts the delimiter value, power level, and pre-allocated compensation delay from the message, and adjusts its configurations accordingly, to support subsequent information exchanges.
• O3 Serial number: The OLT sends a serial number (SN) request to the ONU. The ONU sends its SN to the OLT. After receiving the ONU’s SN, the OLT allocates a temporary ONU-ID to the ONU.
• O4 Ranging: The OLT sends a ranging request to the ONU. After receiving the ranging request from the OLT, the ONU responds with a message carrying its SN and ONU-ID. The OLT calculates the compensation delay and sends it to the ONU in a message. After receiving the message, the ONU sets the compensation delay accordingly.
• O5 Operation: The OLT sends a password request to the ONU. The ONU returns a password to the OLT.
• O6 Intermittent LODS state.
• O7 Emergency Stop state.

Source: hack-gpon.org

Link speed to 2.5Gbit / HGSMII (PMG3000-D20B)

Warning

Please check if your modem does support HSGMII (Proprietary link speeds for SFP+ Modules). Ubiquiti does not for most of their products.
Mirkotik does, so i execute those commands and change the link-Speed to 2500-Base-X in RouterOS/Mikrotik config.

ZYXEL# hal
Hal# set speed 2.5g mode full

Now you might remove the temporary interface on your UDM/Windows Network settings etc.

ifconfig eth9:2 down

Or restart the UDM :)

Adding the Interface

Now its time to add the Interface in the UDM-Pro (Web console.) Just add the PPPoE Details gathered above or set to DHCP if you are using easy-login.
For Telekom customers the user should look like:

Username: AAAAAAAAAAATTTTTTTTTTMMMM@t-online.de
Password: P4ssw0rd (should be 8 Digits)
VLAN: 7

So if you are using an UDM-SE/UDM-Pro your config should look like:

Reprovision

We are not yet done here. The modem has to be "reprovisioned" which can be done via Hotline, technician, or shall happen periodically.

Tip

📞 You can either call the 📞

• Gigabit Hotline +49 800 2266100 - ask for the PLOAM/SLID/Installationskennung and/or ask for reprovision of the Line.
• Generic Hotline +49 800 3301000 - select "Störung"/"Troubleshooting"
  The system needs to know the new Serial or MAC of your Modem etc. If that's done, your setup should look like this (or similiar):

This is by far the most reliable way. Yes, the reprovision sucks, but thats a regulatory Telekom-Thing. $${\color{magenta}Fiber} \space {\color{magenta}rocks!}$$