Tethering A Connection

Overview

Tethering will allow you to share your uplink (internet) connection with other devices. Connman has the ability to tether Ethernet (wired), WiFi or Bluetooth connections, and CMST now has the ability to setup and manage the tether.

By default and design Connman will not tether an ethernet connection out of the box. This limitation can be removed if you really know what you are doing, however if you bypass the limitation CMST will not allow you to turn it on. To enable ethernet tethering you will have to do so using the connmanctl commandline interface. This may be changed in a future release if there is proven need for it.

To tether you really need at least two network interfaces in your computer. One provides the uplink connection to the internet, the other provides an access point for other devices to connect. There are some wifi cards which will support a simultaneous connection to the internet while acting as an access point, but I am not clear if Connman supports this.

Setup a Tether

Connections are tethered at the Technology level, not the Service level. In CMST most of the tab pages deal with Services. Technologies are only seen on the Status tab (the first tab). Since tethering is not used that often the columns dealing with tethering in the Technologies window can be hidden by placing a check in the less box at lower right corner of the Technologies box.

To tether a connection click the On/Off button in the Tethering column for the appropriate Technology. If the Technology you tether is WiFi you will be prompted to provide an SSID name and Password. Once these are set you may change them by clicking the Id:Pass button at the lower right corner. While SSID and Password can be changed, once created they cannot be deleted. When the Technology is tethered any Services that were associated with the Technology are immediately removed. Turning off tethering will automatically reinstate the Services.

Notes on Connecting

1. We've observed that sometimes we need to do a technology rescan on the device trying to connect to the tether in order for the access point to show up.

2. We've also observed that sometimes the device trying to connect to the tether will actually connect (gets to the Ready state) but will not get an internet connection (Online state). For regular WiFi services being in the Ready state instead of Online is almost never an issue, but it does seem to be for a tethered connection. When this happens we can usually disconnect and reconnect again to get the internet connection. We're not sure why this happens and are still looking into it.