Most units using an Ethernet connection use IP communication as their base protocol. IP communication allows several units to connect to the same network and communicate with each other. For this to work, each unit in the network must have a unique IP address. If any units share the same IP address, data can end up in the wrong place and cause communication breakdown. To ensure that no two units have the same IP address you have two options: You can either use DHCP or static IP address.