Interconnect Two Yeastar P-Series PBX Systems

If a company has several branch offices, the frequent calls between the offices will result in large phone bills. By interconnecting the Yeastar P-Series PBX Systems in the offices, phone calls between the offices are regarded as free internal calls even if the offices are in different places, thus greatly reducing the company budgets. This integration guide gives configuration examples on how to set up interconnection between two Yeastar P-Series PBX systems and make free calls.


A company's headquarters, located in New York, has deployed a Yeastar P-Series Cloud Edition, while its branch office, located in Los Angeles, has deployed a Yeastar P570.

To save budget, the company wants to interconnect these two P-Series PBX systems so that employees can make free calls between headquarters and branch office.

The following table lists the detail information of the PBXs in the two offices.
Note: The two PBXs should NOT have the same extension numbers, or the calls between the two PBXs will fail.
Table 1.
Headquarters Branch office
Device Yeastar P-Series Cloud Edition Yeastar P570
Firmware v84.6.0.47 v37.6.0.46
Extension 1000-1200 2000-2050

Network topology diagram

In this guide, the integration between the Yeastar P-Series Cloud Edition and Yeastar P570 is based on the following environment:

Table 2.
Device Network information
Yeastar P-Series Cloud Edition The domain name is
Yeastar P570 The PBX is deployed in a private network and can not access public network.

We provide a diagram to help you understand the integration in a better manner:

For the detailed configuration about interconnecting the two Yeastar P-Series PBX systems, see Connect Two Yeastar P-Series PBX Systems.