Networking & Connectivity Ethernet

Ethernet in marine electronics is a high-speed wired connection used to share bandwidth-intensive data between compatible devices on the same boat. While NMEA 2000 handles lightweight data like GPS position, depth, and engine readings, Ethernet carries the heavy payloads — live sonar images, radar data, and detailed imaging streams — between multiple displays and processing units.

If you want to view the same sonar image on two different screens — one at the helm and one at the bow — those displays typically connect via Ethernet. The sonar data from a single transducer is processed and then distributed over the Ethernet link to multiple displays simultaneously. This eliminates the need for separate transducers at each display location.

The major fish finder brands implement Ethernet networking differently. Garmin uses their proprietary Garmin Marine Network. Lowrance and Simrad share sonar over Ethernet through their respective ecosystems. Humminbird uses Ethernet on their SOLIX and APEX series to network multiple displays. In all cases, Ethernet networking is limited to devices within the same brand — you cannot share sonar data between a Garmin display and a Lowrance unit over Ethernet.

Ethernet also enables radar integration on combo units. A standalone radar dome or array connects to your fish finder display via Ethernet, allowing you to view radar imagery, overlay it on charts, and manage radar settings from your fish finder screen without needing a separate dedicated radar display.