Speedport Smart 4 as internet access router and VoIP client with / to Fritzbox as IP client / Meshmaster with telephone access and two Meshclients.
Problem statement:
Three floors need to be covered with both Wi-Fi and telephone service. VDSL/Dual Stack 1&1 Versatel connection to Telekom technical access point in the basement.
Speedport in the basement, 3 phone numbers 1&1, 3 phone numbers Fonic Sip Trunk, could ultimately be set up in the Speedport with a lot of "creativity / patience", 1st floor Fritzbox Meshmaster, IP Client, telephone already completely set up previously with the same phone numbers.
The other Fritzboxes are also configured as clients for WLAN and telephony in the mesh network, located on the ground floor and in the outdoor area.
All routers are connected via LAN, DHCP is handled by Speedport, and all routers have been assigned fixed IP addresses.
This works to a certain extent, but in the area of telephone there is a problem caused by inconsistencies due to multiple dial-in of the phone numbers; sometimes the Fritzboxes respond, sometimes the Speedport, or sometimes all routers.
Problem solving:
Deactivate the phone numbers in the Speedport and register the Speedport as a VoIP client on the Meshmaster Fritzbox.
All routers should have current firmware version 12/2021 or newer.
It is included as a preparation in the Speedport:
To activate the "IP telephone system", no IP phone should be configured; if one is already configured, delete it!
If phone numbers are already set up, delete them, or at least deactivate them!
Furthermore, it is necessary to define suitable access data in the Fritzbox for the LAN IP Phone, as the input options when configuring the Speedport are severely limited!
Specifically, in the context of the Fritzbox, this means:
Under Telephony Devices - IP Phone "Name", an 8-digit number must be selected which should not begin with 0, eg 12345678!
The same 8-digit number must be entered under "Username" in the login details!
Under "Password" in the login details, a 13-character password must be chosen which may consist of uppercase and/or lowercase letters!
Under login details, check the box for "Allow login from the internet"! Security concerns are negligible, as it is a "virtual SIP number" for internal use!
Now a new phone number must be entered in the Speedport under Phone Numbers - Other Provider:
In the "Telephone number (with area code)" field, enter the 8-digit number that was previously set in the Fritzbox under "Number" and "Username".
For "Provider Name", enter the IP address assigned to the Fritzbox (Meshmaster), eg 192.168.178.1.
Enter the 8-digit number that was previously set in the Fritzbox under "Number" and "Username" in the "Username" field.
For "Password", you must choose the 13-character password that may consist of uppercase and/or lowercase letters and was previously chosen in the Fritzbox.
For "Registrar / Proxy", enter the IP address assigned to the Fritzbox (Meshmaster), eg 192.168.178.1.
Insert at "Port" 5060.
If that doesn't work right away, restarting the Speedport often helps! (Not a reset!!!!!)
After successful registration of the internal SIP phone number, the external phone numbers that the Speedport should have can be specified in the Fritzbox under Telephony Devices - IP Telephone, as needed.
It works reliably and well for me so far, unfortunately, access to the phone books of the Fritzboxes is not possible via the Speedport, but this is tolerable for me in the basement.
