1HARDWARE 2======== 3 4The Bumble Host connects to a controller over an [HCI Transport](../transports/index.md). 5To use a hardware controller attached to the host on which the host application is running, the transport is typically either [HCI over UART](../transports/serial.md) or [HCI over USB](../transports/usb.md). 6On Linux, the [VHCI Transport](../transports/vhci.md) can be used to communicate with any controller hardware managed by the operating system. Alternatively, a remote controller (a phyiscal controller attached to a remote host) can be used by connecting one of the networked transports (such as the [TCP Client transport](../transports/tcp_client.md), the [TCP Server transport](../transports/tcp_server.md) or the [UDP Transport](../transports/udp.md)) to an [HCI Bridge](../apps_and_tools/hci_bridge) bridging the network transport to a physical controller on a remote host. 7 8In theory, any controller that is compliant with the HCI over UART or HCI over USB protocols can be used. 9 10HCI over USB is very common, implemented by a number of commercial Bluetooth dongles. 11 12It is also possible to use an embedded development board, running a specialized application, such as the [`HCI UART`](https://docs.zephyrproject.org/latest/samples/bluetooth/hci_uart/README.html) and [`HCI USB`](https://docs.zephyrproject.org/latest/samples/bluetooth/hci_usb/README.html) demo applications from the [Zephyr project](https://www.zephyrproject.org/), or the [`blehci`](https://mynewt.apache.org/latest/tutorials/ble/blehci_project.html) application from [mynewt/nimble](https://mynewt.apache.org/) 13 14Some specific USB dongles and embedded boards that are known to work include: 15 16 * [Nordic nRF52840 DK board](https://www.nordicsemi.com/Products/Development-hardware/nrf52840-dk) with the Zephyr `HCI UART` application 17 * [Nordic nRF52840 DK board](https://www.nordicsemi.com/Products/Development-hardware/nrf52840-dk) with the mynewt `blehci` application 18 * [Nordic nrf52840 dongle](https://www.nordicsemi.com/Products/Development-hardware/nRF52840-Dongle) with the Zephyr `HCI USB` application 19 * [BT820 USB Dongle](https://www.lairdconnect.com/wireless-modules/bluetooth-modules/bluetooth-42-and-40-modules/bt800-series-bluetooth-module) 20