Maximizing Control Over Your Internet Connection

Part-1: A Guide to Custom Hardware and Configuration


Approx. 7 minutes to complete

photo of Adrian Grimm

By: Adrian Grimm

Software-Developer, -DevOp, -Architect, -Analyst, Scrum-Master and more.

Illustration of internet access

In Germany, fast and high-quality internet is still rare due to lacking infrastructure. As a private customer, it's challenging to get a full internet connection with fixed IPv4 and IPv6 addresses, as well as reverse DNS PTR records. While only a few providers like Vodafone offer such things, other providers require more complicated solutions to do so. Unfortunately, Telekom, a provider of fiber optic connections in Germany, does not offer these options for private customers.

To bypass restrictions, it's advisable to use your own hardware. A VPN with a fixed IP endpoint and reply-to gateway configurations can be helpful. Although Telekom offers a solid modem with the 'Glasfaser-Modem 2,' which in my case allows the use of custom hardware, but my goal was maximum control over the hardware I operate.


A separate modem is recommended for an advanced setup.

Fiber Optic Modem - Telekom Standard


Various options are available, including the following that I found suitable for me.


Firewall + Accesspoint

  • Banana-PI BPI-R3 or R4: Banana Pi BPI-R3
    • I use it just as a dedicated access point with Open-WRT, but could also act as firewall.

GPON ONU ONT Fiber Module

  • GPON SFP Transceiver Module with DDM - GPON SFP ONU Stick with Mac: GPON SFP ONU Stick
    • Customized versions available as 1:1 clone of existing hardware with brand, MAC address, serial number, and device number pre-programmed
    • It is a nice module that is suitable for many modifications - Doku
  • More alternatives and documentation: Hack GPON

As the GPON module has a temperature range of -40 °C to 85 °C and gets and stays hot during operation, I recommend a separate housing, e.g. "TP-Link Gigabit SFP Media Converter MC220L". Despite the temperatures, the passive cooling is sufficient in my case even in a closed multimedia distribution box inside of a wall.

GPON Configuration

To configure the GPON module, connect via SSH with a manual IP address in the same subnet. (The module does not require connected fiber.)

ssh ONTUSER@ -oKexAlgorithms=diffie-hellman-group14-sha1 -oHostKeyAlgorithms=ssh-rsa

The default password is 7sp!lwUBz1.

Configuration Steps

1. PLOAM Password

  • FTTH 1.7
    • Ask the technical hotline
    • sfp_i2c -i11 -s "1234567890"
  • FTTH 2.0 - new "GigabitGeschäftsbereich"
    • No password is required
    • sfp_i2c -i11 -s ""

2. Set Serialnumber

The serial number here ABCD12345678 can be a fictitious one or correspond to a previous module and must be communicated to the technical service together with the fiber optic ID if changed or new:

sfp_i2c -i 8 -s "ABCD12345678“ uci set sfp_eeprom.default.serial_no=ABCD12345678 uci commit

Create full clone

I have not tested this example

set_serial_number HWTC956EABBA
uci set 
uci commit 
sfp_i2c -i 0 -s "HUWAWEI" 
sfp_i2c -i 1 -s "HG8010Hv6" 
sfp_i2c -i 2 -s "0001" 
sfp_i2c -i 3 -s "48575443956EABBA" 
sfp_i2c -i 7 -s "HWTC"
fw_setenv sgmii_mode
uci commit 

Firewall / Router Config

V-LAN and PPPoE configuration is required.

  • VLAN = 7
  • QoS = 0

OPNsense VLAN configuration

OPNsense WAN VLAN assignment

Username / PPPoE: "Anschlusskennung"+"Zugangsnummer"+“0001"+"" Password: 12345678 - yes really, this value is OK

The information can be taken from the letter with the access data from Telekom.

OPNsense WAN PPPoE for Telekom

Useful information for Telekom customers

Transitional solution for new fiber optic connections

Telekom offers a transitional solution "Sofort-LTE" for completely new fiber optic connections via the owner management "Bauherrenservice". This is a relatively solid LTE-based Internet access with 30 to 10 mbit.

Telekom hotlines

Phone numbers

  • Technology: 08003301000
  • Owner management: 08003304174
  • Owner service: +498003301903 / +4908002266100 / +498007733888

Information on authentication

  • Order number (POM = new connection / PSM = existing connection)
  • Customer number
  • Own landline telephone number from Telekom
  • IBAN last 6 digits
  • Address

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