Repository : ssh://git@open-mesh.org/doc

On branches: backup-redmine/2019-09-14,master

commit 62014609c4ed6c00273259539a064e9d34b5ef4d Author: Linus Lüssing linus.luessing@c0d3.blue Date: Fri May 3 23:34:34 2019 +0000

doc: batman-adv/Broadcast

62014609c4ed6c00273259539a064e9d34b5ef4d batman-adv/Broadcast.textile | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/batman-adv/Broadcast.textile b/batman-adv/Broadcast.textile index 62107cb..3733a63 100644 --- a/batman-adv/Broadcast.textile +++ b/batman-adv/Broadcast.textile @@ -14,12 +14,14 @@ To avoid frames looping around forever (a broadcast storm) an originating batman

h2. Interface Type: WiFi vs. Others

-In 802.11 based wireless networks broadcast transmissions have one specific downside compared to unicast: While for unicast transmissions a missing frame is detected and retransmitted ("ARQ":https://en.wikipedia.org/wiki/Automatic_repeat_request). +In 802.11 based wireless networks broadcast transmissions have one specific downside compared to unicast: While for unicast transmissions a missing frame is detected and retransmitted ("ARQ":https://en.wikipedia.org/wiki/Automatic_repeat_request) a broadcast transmission is performed only once, with no acknowledgements.

To compensate for that batman-adv (re-)broadcasts a frame on a wireless interface not just once but three times when classic flooding is used.

Furthermore, for the second and third broadcast a delay of 5ms is applied for each to increase the probability that one of the broadcasts arrives.

+Last but not least 802.11 broadcasts are usually performed at the lowest Wifi bitrate. If a high broadcast throughput is needed, it is therefore usually recommended to increase the Wifi rate for multicast transmissions in the wifi driver. + h2. Gateway Feature: DHCP Optimizations

todo