Some Dect phones can act as their own "exchange" - dial 1 for handset 1, 2 for handset 2 &c obviously depending on the number of handsets supported and allows small businesses to have a basic system. 9 is then used to access the PSTN from any handset. It is almost certainly removable - if that is what you want to do.
As for broadband - provided the line is straight through to the business unit there should be no reason, I can think of, as to why it will not work with that.
M H C
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