I have a number siemens optipoint 500 economy phones.
They have been used in an office environment in which the networking of the phones were managed by a third party. I would now like to use them in my new building to allow transfer of calls to other rooms and phoning handset to handset.
I've got 1 landline coming into the building and would like any of the phones to be able to pick up the call and transfer to another phone. Luckily all the phones are in the same large room and so is the landline so I shouldn't need to do anything in the walls.
Can anyone point me to what additional hardware I need and any info on how to get this setup?