Decentral offices / busy notification / central post

the folowing situation

Is there a possibility to have central posts (workstation 1/2) who is busy ia a switchboard one more asterisk PBX’s. All voice
connections still go via the ISDN interfaces … you could say signaling via IP voice via ISDN.

Hope someone has examples how to configure this.

Happy *
Jos Dieperink

sounds very doable.