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LAN35H08HR & LAN35E08HR User’s Manual
Figure 10: LAN35E08HR Block Diagram
Figure 11: IDAN-LAN35E08HR Block Diagram
BroadCom Gig-Ethernet Switch
The main components of the LAN35H08HR are the two BroadCom BCM53115 Gigabit Ethernet switch. They are industrial temperature rated,
5 port Gigabit Ethernet switches that are connected together to make a 10 port switch. This switch contains 10 full-duplex 10/100/1000 BASE-
TX Ethernet transceivers for network interfacing. One of these ports is used in conjunction with the WG82574IT for a host port. This allows the
LAN35H08HR to work as its own mini-server in a stacked system. In a stand-alone system the BroadCom switch acts as a basic Ethernet
switch. Any port can be used as an upstream port to supply a connection to the other ports.
Jumbo Frame Support
The Broadcom Ethernet switch is capable of forwarding Ethernet frames up to 9720 bytes. The maximum frame size supported by the Intel
Ethernet controller is 9014 bytes. To use Jumbo frames, it must be enabled in the Ethernet Controller driver settings (e.g. via the Device
Manager in Windows). Until this is enabled, the Intel controller will drop any Jumbo frames it receives. Note that to use Jumbo frames
effectively, all devices connected to the network must have Jumbo frames enabled, AND must agree on the frame size (mismatched frame
sizes will result in dropped packets).
