There are multiple sides to the HH network today. They are: HHUS; HHAP; HHEU and HHUX (Experimental).
On HHUS, HHAP, and HHEU we only allow supported endpoints to connect to their respective network. These endpoints can be any device currently listed in our Supported Endpoints document, or your own PBX.
If using your own PBX, please be sure to read our FAQs for further info on how your PBX is supported. Running a PBX instead of a phone is only recommended for advanced voip users. We will only support PBX interconnection over the IAX protocol, so your PBX must support IAX. We do not support 3CX or other SIP based PBX systems.
If your phone is not on the Supported Endpoints list, you may open an HHUX New Line Request to have your phone setup on the experimental network.