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OpenWRT Build

The SudoMesh project maintains firmware builds for a certain set of Wireless routers (home nodes) and extender antennas. The code used to create these builds is available in SudoWRT-Firmware.

Included Software Packages

The SudoWRT-Firmware code contains a configured list of software packages that are included within the builds for home nodes and the extender antennas.


uhttpd is an efficient and stable web server daemon, suitable for lightweight tasks commonly used with embedded devices and proper integration with OpenWrt's configuration framework (UCI). In particular, it is configured by default for the LuCI web interface to administer OpenWrt. SudoMesh uses it's own SudoWRT-Web-UI, see Mesh/Firmware/Web_Admin_Development for more information.


uhttpd-mod-ubus is a module for uhttpd that acts as a proxy between the HTTP interface of the home node, and the local ubus that is available to processes running on the home node.

Web Interface

The web interface for OpenWRT is supported by a framework of components known as LuCI.

Discovering Network Configuration


Run ip addr show to discover the IP addresses assigned to your home node.


Use iw to inspect the wireless interfaces that are configured.

iw phy will display physical interfaces and capabilities, seeing each radio that is available.

iw dev will display devices

Switch Configuration

swconfig is an OpenWRT binary for switch configuration. The routers have a switch that can be used to recognized Virtual LAN (VLAN). You 5 different Ethernet devices, but it's not that there are 5 different Ethernet interfaces, but instead the router is a switch that uses VLANs. You can configure traffic coming in on a specific VLAN so that it can be recognized (VLAN tagged) and routed as needed. You can have multiple layer 2 Ethernet networks on the same wire.

Use swconfig to see if there are other switches available by running `swconfig list`. Once you identify the device, run `swconfig dev eth0 show`. You will see the various physical ports first, then you will see each VLAN.

The uplink port may show up in the list depending on the device.

Get the IP for the extenders from: less /etc/config/notdhcpserver

There is a library that can be used to read from this config file, as well as a command, called `uci` (unified configuration interface) that allows you to obtain information such as the IP address of the extender nodes.

 uci show notdhcpserver
 uci show notdhcpserver[0].addresses


Babel provides the entire routing table for the network.

 babeld -i

This provides you with the data on every node on the entire network. Every node and extender node connected to the mesh that you can reach will be listed. babeld is the daemon that broadcasts routes that are available via the ad-hoc network connection ( The age shown in the output provides how long ago the node announced it's existence on the network. When a node becomes too old, it gets dropped from the table.

The mesh node will always try to route via the node that has the lowest metric. It tracks the metric also. The 'nexthop' value helps provide information used for routing. It's very lightweight, not complex.

SudoMesh uses a modified version of babeld, with support for adding or removing interfaces while babeld is running added.

Exit Node

Every home node routes traffic to the exit node that was setup for This exit node acts as the gateway from the Virtual Private Network (VPN) used by to contain the SudoMesh network to the Internet.

Extender Antenna Nodes

A client/server system called notdhcp was developed to help extender nodes obtain an IP address and establish a trust relationship with a SudoMesh home node upon physical connection.

As of May 2016 the wired interface between the extender node and the home node does not use SSL for communication, however this is planned for implementation after the completion of the ubus-https-forwarder.

The ubus-https-forwarder software will be responsible for enabling the home nodes to receive requests on the HTTP interface provided by uhttpd-mod-ubus that are addressed for the extender nodes instead of the home node, and then forwarding those requests to the extender nodes.

Authentication is required when accessing the ubus HTTP interface, which may not yet be setup for the extender nodes. A possible approach is to update notdhcp so that it provisions a password to the extender node upon physical connection. Then the notdhcp server could make the password available to the home node or the web interface client.