# Communicating with the Sounder S500

The Cerulean Sounder S500 features 3 hardware connection options. 

• Ethernet (100Mb/sec)

• USB (12Mb/sec)

• 3.3V Serial (115kbaud). 

After each power up, all interfaces are polled. The first one to send a valid packet is selected as the host, and the remaining interfaces are disabled. 

**API Compatibility:** S500 communication uses a binary packet format compatible with the Blue Robotics [Ping-Protocol](https://github.com/bluerobotics/ping-protocol). 

**API Documentation:** Please see Appendix F for the definitions of the officially supported packet formats. These packet types are recommended for new applications targeting the S500 sounder. 

**Network connection:** Communication happens via UDP or TCP on port 51200. The default IP address for the S500 is 192.168.2.92. The IP address can be configured using SonarView [device discovery](https://docs.ceruleansonar.com/c/v/sonarview/device-discovery-and-ip-addressing).