Simple question: Why IP Phones have dialplans?

THis is the scenario:

  1. You buy a brand new IP Phone
  2. You go to it default IP to configure the Extension, password, etc…
  3. BAM! Why you also need to configure a dialplan?
    (Why not use the dialplan directly from the PBX?)

Analog phones are conected directly via dedicated swich port, but they get the dialplans directly from the PBX. Why enginiers invent an additional dialplan in the IP Phone? WHy?

Because all the digits are sent in the INVITE request. It is basically the same reason that you have to press call at the end of the number when using a mobile phone.

I believe Asterisk supports overlap dialing, where numbers are rejected as incomplete until a full number is provided, but I don’t think many phones support this.