Re: [B.A.T.M.A.N.] batman-adv 2012.2.0 released

[Gioacchino Mazzurco <gmazzurco89@gmail.com>]

Great job guys and many thanks!!

On 06/15/12 20:56, Marek Lindner wrote:
> 
> Today, the B.A.T.M.A.N. team releases batman-adv 2012.2.0, packed with new 
> features and improvements in various subsystems as well as the usual set of 
> fixes and cleanups. As the kernel module always depends on the Linux kernel it 
> was compiled against, it does not make sense to provide binaries on our 
> website. As usual, you will find the signed tarballs in our download section:
> 
> http://downloads.open-mesh.org/batman/releases/batman-adv-2012.2.0/
> 
> as well as prepackaged binaries in your distribution.
> 
> 
> Important changes
> -----------------
> 
> This release comes with a completely rewritten bridge loop avoidance (also 
> known as bridge loop avoidance II). The concept of the first bridge loop 
> avoidance was simple and worked well in small size LANs while larger networks 
> suffered from the overhead. The new concept is very different and requires 
> changes in your batman-adv configuration. If you were using the bridge loop 
> avoidance you should consult our documentation before upgrading your 
> network(s).
> 
> The default "per hop" penalty was increased to encourage batman-adv to take 
> shorter routes. If you notice altered routing behavior and are unhappy with 
> the result you should revisit the hop penalty configuration option.
> 
> 
> Thanks
> ------
> 
> Thanks to all people sending in patches:
> 
>  * Antonio Quartulli <ordex@autistici.org>
>  * Danny Kukawka <danny.kukawka@bisect.de>
>  * David S. Miller <davem@davemloft.net>
>  * Eric Dumazet <eric.dumazet@gmail.com>
>  * Linus Luessing <linus.luessing@web.de>
>  * Marek Lindner <lindner_marek@yahoo.de>
>  * Simon Wunderlich <siwu@hrz.tu-chemnitz.de>
>  * Sven Eckelmann <sven@narfation.org>
>  * Xabier Rodriguez <xrb@kalrong.net>
> 
> and to all those that supported us with good advice, code review and/or 
> rigorous testing:
> 
>  * Al Viro <viro@ZenIV.linux.org.uk>
>  * David Laight <David.Laight@aculab.com>
>  * Jo-Philipp Wich <jow@openwrt.org>
>  * Martin Hundebøll <martin@hundeboll.net>
> 
> 
> batman-adv
> ----------
> 
> The new bridge loop avoidance certainly is the most prominent of the new 
> features this release has to offer (completely replacing the old bridge loop 
> avoidance mechanism). The major design goals were performance and scalability. 
> Since the old implementation was relying on a single gateway to be the master 
> gateway to the LAN for everybody else it created a performance bottleneck. 
> Furthermore, the LAN was used to send traffic to and receive data from the 
> master gateway. With the number of bridged gateways grew the amount of 
> broadcast traffic in the LAN. The new bridge loop avoidance splits the client 
> responsibility amongst all participating gateways. Each gateway "claims" the 
> clients it feels responsible for and ignores the traffic from all other 
> clients to avoid the bridge loop. It also is able to handle multiple VLANs on 
> top of the batX interface connected to different topologies. All details about 
> the loop avoidance mechanism are explained in our documentation section.
> 
> The routing code also received lots of attention: The recently added routing 
> protocol abstraction was further polished and extended to better accommodate 
> the needs of alternative routing protocols. B.A.T.M.A.N. IV protocol has been 
> enhanced with an additional flag to apply stricter forwarding rules to OGMs 
> which allows the protocol to avert routing loops in certain corner cases. 
> Also, the B.A.T.M.A.N. IV sequence numbers are now randomized at startup to 
> reduce the probability of a collision and thus, slowing down the protocol in 
> the startup phase. Rerouting of unicast payload packets during a roaming phase 
> is handled with greater efficiency to avoid as much packet loss while roaming 
> as possible. 
> 
> All manual HZ-jiffies-calculations have been replaced with the in-kernel 
> jiffies_to_msecs() function. To facilitate comprehension of the code base the 
> ETH_ALEN macro is used instead of hardcoded numeric constants. The batman-adv 
> internal bitarray operations have been converted to the efficient in-kernel 
> bitmap operations. It was discovered that the TT-Request packet did not always 
> send the tt-crc field in network byte order, thereby invalidating the packet. 
> This has been fixed alongside the suboptimal DHCP option list parser used by 
> the gateway extension. OGM sequence numbers now are always printed as unsigned 
> long to avoid misinterpretation while printing the numbers in the debug log.
> 
> 
> batctl
> ------
> 
> The batctl utility supports the new bridge loop avoidance by providing an 
> option to conveniently enable/disable the bridge loop avoidance and exports 
> the bridge loop avoidance claim table. It will also warn about features that 
> haven't been compiled into batman-adv such as debug log and bridge loop 
> avoidance. The mini-tcpdump learned to display the newly added 'not best hop 
> flag' when parsing OGMs. 
> 
> 
> Happy routing, 
> The B.A.T.M.A.N. team