Ethernet Interfaces

Two Ethernet interfaces are available which are designed for different requirements.

 

Ethernet Interface LAN 0

This Ethernet interface is connected to the internal USB hub and to the left RJ45 socket marked LAN 0. The Ethernet connections are ports with a transmission rate of 100 Mbit/s each. Since the USB interfaces and the Ethernet interfaces share the USB bandwidth, the throughput on the LAN 0 interface may decrease if you connect additional USB devices. An overview of the USB subsystem can be found here.

You can address this interface in the software as eth0.

The MAC address for this Ethernet interface can be found on the front of the housing under LAN 0 and in the file “/boot/config.txt”. You can change the MAC address for eth0 here, if necessary. If no MAC address is entered in the file “/boot/config.txt”, e.g. because you have uploaded a new image, a unique MAC address is calculated from the serial number of the Compute Module.

Ethernet Interface LAN 1

Here you can connect up to three additional devices to the network. This Ethernet interface is also connected to the internal USB hub and connected via a 1:3 switch to the three right-hand RJ45 sockets marked LAN 1/SWITCH.

The MAC address for this Ethernet interface can also be found on the front of the housing (LAN 1).

You can address this interface in the software as eth1.

The MAC address is stored in the file “/boot/config.txt”. You can change the MAC address for the Ethernet interface LAN 1 (eth1) here, if necessary. In addition, the MAC address is stored in a separate memory module of the Ethernet interface LAN 1 (eth1). This factory MAC address is used if no MAC address is entered in the file “/boot/config.txt”, e.g. because you have uploaded a new image.

Bandwidth

The network interface supports 10 and 100 MBit/s with half and full-duplex capability with autonegotiation activated.