batman-advanced

Batman-advanced is a new approach to wireless networking which does no longer operate on the IP basis. Unlike B.A.T.M.A.N, which exchanges information using UDP packets and sets routing tables, batman-advanced operates on ISO/OSI Layer 2 only and uses and routes (or better: bridges) Ethernet Frames. It emulates a virtual network switch of all nodes participating. Therefore all nodes appear to be link local, thus all higher operating protocols won't be affected by any changes within the network. You can run almost any protocol above B.A.T.M.A.N. Advanced, prominent examples are: IPv4, IPv6, DHCP, IPX.

Pros and Cons

Pros:

  • supports any Ethernet-capable protocol (IPv4, IPv6, ARP, DHCP ...)
  • no manual IP assignment, just use DHCP
  • easy integration of attached networks (no manual HNA fiddling), just put the bat0 in the bridge with your other devices. You can for example build a roaming network of Access Points with this technique.
  • Not affected by your Firewall (but you can secure the payload traffic, of course)

Cons:

  • no gateway handling inside of B.A.T.M.A.N. (DHCP/IPv6 autoconf/static routes will work but B.A.T.M.A.N. won't help to choose the best gateway for you)

batctl (former battools)

Since the nodes participating in the B.A.T.M.A.N. Advanced switch are completely transparent for all protocols above layer 2, we needed to build our own diagnostic tool batctl. This tool contains a layer 2 version of ping, traceroute and tcpdump. It also offers a configuration interface for the kernel module as well as an integrated log reader. Further information can be found in the enclosed README file.

Userland vs Kernelland

The userland implementation of batman-advanced was a proof of concept implementation to verify that the concept is working. Unfortunately, switching packets in userland is very expensive in terms of cycles, as each packet has to be read() and write() to the kernel and back, which limits the sustainable bandwidth especially on low-end devices. To have good support for these devices as well, we implemented batman-adv as a kernel driver, which is now the preferred version. It can be controlled via the /proc file system and works transparently. The userland remains unmaintained and has been removed from the subversion repository.

Documentation

See the UserDocs page.

Get it

see the Download page