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Maximum number of calls over the FRITZ!Box

The maximum number of calls that can be conducted over the FRITZ!Box is limited by the interface (for example DECT, LAN, FON 1, FON S0) and respective type of connection (internet, analog, ISDN). You can conduct eight calls over the internet, an additional call from an analog landline, and two additional calls from an ISDN line. Below you will find the number of calls possible with each type of interface. To find out how many calls you can conduct with your devices, you must do a little calculating. We have given you a couple of calculation examples.

1 IP telephones

Two connections are established when making internet calls with an IP telephone that is configured for the "LAN/WAN" port. Therefore, you can conduct a maximum of four internet calls at the same time with IP telephones, and the number of possible calls is reduced.

Examples:
If an IP telephone is being used to conduct an internet call and another IP telephone is used for a landline call, five additional internet calls can be conducted with the other interfaces.
If two IP telephones are being used to conduct internet calls, four additional internet calls can be conducted using the other interfaces.
If four IP telephones are being used to conduct internet calls, no additional internet call can be conducted using the other interfaces.

2 DECT devices

You can conduct a maximum of three calls from your landline and/or over the internet at the same time using cordless telephones that are registered with the FRITZ!Box's DECT base station.

Examples:
If three cordless telephones and an IP telephone are being used to conduct internet calls, three additional internet calls can be made using the other interfaces.
If three cordless telephones and two IP telephones are being used to conduct internet calls, one additional internet call can be conducted using the other interfaces. You cannot conduct an additional call with an IP telephone.

3 Analog devices

One call can be conducted with each of the analog devices connected to the socket "FON 1" or "FON 2".

4 ISDN devices

A maximum of two calls can be conducted at the same time from the landline and/or the internet using ISDN devices connected to the "FON S0" socket.

5 Integrated answering machine and fax function

The answering machine and the fax can each accept one call. All other callers hear a busy signal, even if you set up more than one answering machine. You cannot send a fax while receiving a fax, and you cannot receiving a fax while sending one.