Reticulum supports using many kinds of devices as networking interfaces, and allows you to mix and match them in any way you choose. The number of distinct network topologies you can create with Reticulum is more or less endless, but common to them all is that you will need to define one or more interfaces for Reticulum to use.

The following sections describe the interfaces currently available in Reticulum, and gives example configurations for the respective interface types.

For a high-level overview of how networks can be formed over different interface types, have a look at the Building Networks chapter of this manual.

In addition to the built-in interface types, Reticulum is fully extensible with custom, user- or community-supplied interfaces, and creating custom interface modules is straightforward. Please see the custom interface example for basic interface code to build upon.

The AutoInterface enables communication with other discoverable Reticulum nodes over any kind of local Ethernet or WiFi-based medium. Even though it uses IPv6 for peer discovery, and UDP for packet transport, it does not need any functional IP infrastructure like routers or DHCP servers, on your physical network.

If you have firewall software running on your computer, it may block traffic required for AutoInterface to work. If this is the case, you will have to allow UDP traffic on port 29716 and 42671.

As long as there is at least some sort of switching medium present between peers (a wired switch, a hub, a WiFi access point or similar, or simply two devices connected directly by Ethernet cable), it will work without any configuration, setup or intermediary devices.

For AutoInterface peer discovery to work, it’s also required that link-local IPv6 support is available on your system, which it should be by default in all current operating systems, both desktop and mobile.

Almost all current Ethernet and WiFi hardware will work without any kind of configuration or setup with AutoInterface, but a small subset of devices turn on options that limit device-to-device communication by default, resulting in AutoInterface peer discovery being blocked. This issue is most commonly seen on very cheap, ISP-supplied WiFi routers, and can sometimes be turned off in the router configuration.

# This example demonstrates a bare-minimum setup

# of an Auto Interface. It will allow communica-

# tion with all other reachable devices on all

# usable physical ethernet-based devices that

# are available on the system.

[[Default Interface]]

type = AutoInterface

enabled = yes

# This example demonstrates an more specifically

# configured Auto Interface, that only uses spe-

# cific physical interfaces, and has a number of

# other configuration options set.

[[Default Interface]]

type = AutoInterface

enabled = yes

# You can create multiple isolated Reticulum

# networks on the same physical LAN by

# specifying different Group IDs.

group_id = reticulum

# You can also choose the multicast address type:

# temporary (default, Temporary Multicast Address)

# or permanent (Permanent Multicast Address)

multicast_address_type = permanent

# You can also select specifically which

# kernel networking devices to use.

devices = wlan0,eth1

# Or let AutoInterface use all suitable

# devices except for a list of ignored ones.

ignored_devices = tun0,eth0

If you are connected to the Internet with IPv6, and your provider will route IPv6 multicast, you can potentially configure the Auto Interface to globally autodiscover other Reticulum nodes within your selected Group ID. You can specify the discovery scope by setting it to one of link, admin, site, organisation or global.