How to configure DisplayLink Ethernet
Half duplex connections, eg to network hubs, are not supported. A network link will not be established if connected to a half duplex port.
There are Ethernet features that can be configured. The screenshots below show the configuration on Windows 7, however the configuration is the same for all other Windows versions.
Note: it is unlikely you will need to configure any of these settings in a home environment. Contact your administrator to find out if you need to configure any of the settings in this section.
Advanced Ethernet features
Quick Links:
- Opening Advanced Features
- Configuring the adapter MAC Address
- Configuring MAC address cloning or MAC address pass-through
- Automatic wired/wireless MAC address cloning or MAC address pass-through
- Configuring the Link Speed
- Configuring the adapter VLAN ID
- Configuring Wake on LAN
- Configuring Ethernet settings remotely
- Jumbo Frames
- Uninstalling just the Ethernet driver
Opening the advanced Ethernet features
To access the advanced Ethernet features, Type
ncpa.cpl
into the Start menu search box:Windows 7:
Windows 8.1:
Windows 10:
The "Network Connections" window opens. Locate the "DisplayLink USB Gigabit Network":
Right click on the icon and choose "Properties",then select "Configure…"
Choose the "Advanced" tab
Configuring the adapter MAC address
By default, every DisplayLink Ethernet port has its own unique layer 2 MAC address stored in the chip firmware. This MAC address will be used if the option Not Present is selected. The MAC address can be changed in the advanced properties.
To change the MAC address, Select the Value option and enter the new MAC address in the format XXXXXXXXXXXX, where X is a hexadecimal digit between 0 and F.
Click "OK" to apply the change
Additional MAC address configuration from 8.1 host software
See the section Configuring Ethernet settings remotely below for additional MAC address configuration options.
Configuring MAC address cloning or MAC address pass-through
You can configure the MAC address of the DisplayLink Ethernet port from various sources. These sources are listed in the priority order they will be applied below:
- Selected OEM
laptop with dock MAC address passthrough on available configuration. You may reach out to technical support for details.
- MAC address set per Ethernet adapter interface under
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Class\{4D36E972-E325-11CE-BFC1-08002bE10318}\XXXX
with a string value of NetworkAddress and a value in the format XXXXXXXXXXXX, where X is a hex digit between 0. - MAC address set under
HKEY_LOCAL_MACHINE\System\CurrentControlSet\services\dlcdcncm\Parameters\
with a string value of MacAddressOverride and a value in the format XXXXXXXXXXXX, where X is a hexadecimal digit between 0 and F. - Automatic wired/wireless MAC address cloning / pass-through
- Default MAC address of the dock hardware is used
IT managers need to be careful when choosing and configuring their MAC address passthrough policy that more than one interface with the same MAC address cannot be connected to the same network at the same time. Having duplicate MAC addresses on a network will cause network issues.
Automatic wired/wireless MAC address cloning or MAC address pass-through
From DisplayLink USB Graphics Software for Windows with Hot Desking version 10.1 (available from our corporate download section), you can enable automatic configuration of MAC address pass-through. It does not replace existing possibility of configuring MAC address pass-through, but rather extends it.
Feature is controlled by registry key under
When feature is enabled and dock is plugged-in, registry key
Existing MAC address pass-through registry key value is backed-up to registry key
To choose the best MAC address, following rules are applied:
The link speed can be set Auto negotiate (default), 10Mbps full duplex, 100Mbps full duplex or 1Gbps full duplex. Half duplex speeds are not supported.
The VLAN tag can be set. By default the VLAN tag is set to 0, which will transmit all packets priority tagged. The VLAN tag can be between 1 and 4095.
On Windows 7 and Windows 8 VLAN Tagging will also need to be enabled under the "Priority and Vlan" menu:
Click "OK" to apply the change
Wake on LAN is enabled and disabled under the Power Management tab:
To enable Wake on LAN, which will wake the computer on Link Up and Magic packet, check the box to Allow this device to wake the computer.
Note: This option will be greyed out if not supported by your PCs USB Host controller or BIOS.
Wake on Magic Packet also needs to be enabled under the "Advanced" tab:
The DisplayLink device will need to be disconnected and reconnected to the USB bus before the settings take effect.
Wake on LAN will wake the PC from an S3 (suspend or sleep) state. It may fail if the PC turns off the USB connection during S3 on battery power. It will not wake the PC from an S4 (Hibernate) or S5 (Off) state.
Wake on LAN will wake the PC from an S3 (suspend or sleep) state. It may fail if the PC turns off the USB connection during S3 on battery power. It will not wake the PC from an S4 (Hibernate) or S5 (Off) state.
This section is designed for IT administrators only to allow them to remotely set Ethernet parameters. This section should only be followed if you are an advanced user, familiar with the Windows registry.
It is possible to set the Ethernet options remotely through the Windows registry on the PC. The settings are stored under:
There is a list of numeric keys under here, starting at 0000. Each of the keys are the settings for a network card. This can be found under the details tab, under the Driver Key properties. In the example below, it is 0022:
The parameters are held below this registry key.
Network Address
The network address can be set by adding a new String Value, with the Name NetworkAddress. The value should be in the format XXXXXXXXXXXX, where X is a hex digit between 0 and F.
VLAN ID
The VLAN ID can be set by adding a new String Value, with the Name VlanID. The value should be between 0 and 4095. Setting 0 will disable tagging.
Wake on LAN
Wake on LAN is enabled by setting the PnPCapabilities to “0”. To disable Wake on LAN, set PnPCapabilities to “110” (Hex).
To set the Wake on LAN method, add a String Value with the Name WakeOnLan and a value. A list of the possible values are stored below here in the registry under
Jumbo frames are not supported on DL-3xxx, DL-5xxx or DL-6xxx series Ethernet ports. Disable jumbo frames on any network with DisplayLink Ethernet ports connected, otherwise problems could be found with network behaviour.
In a corporate environment, it might be desired that the Ethernet driver is not installed to prevent the Ethernet port of the dock being available and a security risk. The Ethernet driver can be uninstalled after deploying DisplayLink software by:
HKEY_LOCAL_MACHINE\Software\Displaylink\Core
with string value MACAddressPassthrough
and a value of ‘1’.When feature is enabled and dock is plugged-in, registry key
HKEY_LOCAL_MACHINE\System\CurrentControlSet\services\dlcdcncm\Parameters\MacAddressOverride
is filled in with MAC address cloned from existing ethernet adapter. It is strongly advised to have one network cable connected to the system to avoid situation where two adapters with the same MAC address are connected to the network.Existing MAC address pass-through registry key value is backed-up to registry key
HKEY_LOCAL_MACHINE\System\CurrentControlSet\services\dlcdcncm\Parameters\MacAddressOverrideBackup
which is restored, when dock is unplugged.To choose the best MAC address, following rules are applied:
- MAC address is cloned from wired adapter first.
- If case on no wired adapter, wireless (802.11) device is chosen when available.
- Link status (is adapter connected and active) is not checked. This is planned for a future version.
- Any DisplayLink docks, virtual adapters like VPN, VMWare, VirtualBox or Bluetooth adapters are ignored.
- OEM laptop + dock MAC address passthrough functionality takes priority and disables the automatic configuration of MAC address cloning of wired/wireless network adapters.
Configuring the Link Speed
The link speed can be set Auto negotiate (default), 10Mbps full duplex, 100Mbps full duplex or 1Gbps full duplex. Half duplex speeds are not supported.
Configuring the adapter VLAN ID
The VLAN tag can be set. By default the VLAN tag is set to 0, which will transmit all packets priority tagged. The VLAN tag can be between 1 and 4095.
On Windows 7 and Windows 8 VLAN Tagging will also need to be enabled under the "Priority and Vlan" menu:
Click "OK" to apply the change
Configuring Wake on LAN
Wake on LAN is enabled and disabled under the Power Management tab:
To enable Wake on LAN, which will wake the computer on Link Up and Magic packet, check the box to Allow this device to wake the computer.
Note: This option will be greyed out if not supported by your PCs USB Host controller or BIOS.
Wake on Magic Packet also needs to be enabled under the "Advanced" tab:
The DisplayLink device will need to be disconnected and reconnected to the USB bus before the settings take effect.
Wake on LAN will wake the PC from an S3 (suspend or sleep) state. It may fail if the PC turns off the USB connection during S3 on battery power. It will not wake the PC from an S4 (Hibernate) or S5 (Off) state.
Configuring Wake on Magic Packet only
To allow Wake on Magic packet only, also check the option to "Only allow a magic packet to wake the computer". Also Enable Wake on Magic Packet under the Advanced Tab:
Wake on LAN will wake the PC from an S3 (suspend or sleep) state. It may fail if the PC turns off the USB connection during S3 on battery power. It will not wake the PC from an S4 (Hibernate) or S5 (Off) state.
Configuring Ethernet settings remotely
This section is designed for IT administrators only to allow them to remotely set Ethernet parameters. This section should only be followed if you are an advanced user, familiar with the Windows registry.
It is possible to set the Ethernet options remotely through the Windows registry on the PC. The settings are stored under:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Class\{4D36E972-E325-11CE-BFC1-08002bE10318}
There is a list of numeric keys under here, starting at 0000. Each of the keys are the settings for a network card. This can be found under the details tab, under the Driver Key properties. In the example below, it is 0022:
The parameters are held below this registry key.
Network Address
The network address can be set by adding a new String Value, with the Name NetworkAddress. The value should be in the format XXXXXXXXXXXX, where X is a hex digit between 0 and F.
VLAN ID
The VLAN ID can be set by adding a new String Value, with the Name VlanID. The value should be between 0 and 4095. Setting 0 will disable tagging.
Wake on LAN
Wake on LAN is enabled by setting the PnPCapabilities to “0”. To disable Wake on LAN, set PnPCapabilities to “110” (Hex).
To set the Wake on LAN method, add a String Value with the Name WakeOnLan and a value. A list of the possible values are stored below here in the registry under
Ndi/params/WakeOnLan/enum
. Use the Name (0 to 3) of these enums as the
Value for WakeOnLanJumbo frames
Jumbo frames are not supported on DL-3xxx, DL-5xxx or DL-6xxx series Ethernet ports. Disable jumbo frames on any network with DisplayLink Ethernet ports connected, otherwise problems could be found with network behaviour.
Uninstalling just the Ethernet driver
In a corporate environment, it might be desired that the Ethernet driver is not installed to prevent the Ethernet port of the dock being available and a security risk. The Ethernet driver can be uninstalled after deploying DisplayLink software by:
- Running pnputil to find the inf file for the driver in the Windows driver store. Eg:
pnputil -a C:\Program Files\DisplayLink Core Software\CdcNcmDriver\dlcdcncm.inf
- Process pnputil output to get "oemXX.inf" file name
- Remove the Ethernet driver with the command
pnputil -f -d oemXX.inf