SECN User Guide
5. Overview of SECN Operation
This configuration uses Batman-advanced for the mesh rather than Batman as used in earlier
firmware versions. Batman-advanced uses a different mesh protocol to batman and so the two won't
interoperate on the same mesh.
The MP device provides two physical network interfaces, Ethernet cable and wireless, which are
configured as follows:
•
The
eth0
interface operates on the MP Ethernet cable connection.
•
Two wireless interfaces,
ath0
and
ath1
, are set up on the wireless interface
wifi0
.
•
Batman-adv is configured to run on the
ath0
interface using the
batctl
command and
generates the
bat0
interface.
•
The second wireless interface,
ath1
, is set up to operate as a WiFi access point using the
iwconfig
command.
•
The
bat0
,
ath1
and
eth0
interfaces are bridged (
br
-
lan
) together in each MP and assigned a
static IP address, and thus, due to the operation of the mesh via
bat0
, all the
ath1
and
eth0
interfaces of all the MPs in the mesh are similarly bridged.
•
The default IP address range used for the
br-lan
interface is 10.130.1.xxx
The mesh will operate in a stand-alone configuration, simply connecting attached devices together
and providing telephony between devices. Alternatively the mesh may be interconnected to a LAN
to provide access to additional resources, including internet connectivity.
If one of the MP devices is connected via Ethernet cable to a LAN router, then all WiFi and
Ethernet interfaces connected to the meshed MPs will have access to the LAN resources.
If there is a DHCP server running on the LAN (eg in the router) then devices configured as DHCP
clients connected to the MPs will acquire an IP address just as if they were connected directly to the
LAN.
Note that there is no DHCP server running in a stand-alone mesh arrangement by default, and so in
this case, attached devices would need to be statically configured for their IP address.
5.1 IP Address Range for MPs
It should be noted that the IP address used for the
br-lan
bridge in the MP devices needs to be
configured during setup, and
may
or
may not
be made to lie in the IP address space used on the
LAN to which the mesh may be connected. Operation is essentially the same in both cases, but care
must be taken to manage the address space in the former case.
IP addresses assigned to MP devices are static. If the IP addresses used for the MP devices lie in the
same address space as the LAN, then the DHCP server and other devices on the LAN must be
appropriately configured so that the addresses assigned to the MP devices are left free in order to
avoid IP address conflicts. In this arrangement, the MP devices will appear on the LAN just as any
other device with a static IP address, and they may be accessed for management via browser or ssh
terminal session.
Conversely, if the IP address range used for the MP devices is separate to that used on the LAN, the
MP devices will not appear on the LAN and there is no need to reserve the address space. In order
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