[Berlin-wireless] Best Practice on updating to ff_1.5.13

Bluse h2o-post
Mo Jul 9 21:11:58 CEST 2007

Hello Freinfunkers,

Just today I updated our hole Mesh with 42 nodes from ff firmware release
1.5.11 to 1.5.13. In summary, with some changes, I would say.. the fucking
fastest mesh network we ever had since november 2006 ;o)

Here are some experience and changes I made today.

-because of the mrate threshold of 6MBit/sek, all nodes lost the links
rechable below this rate. My recommendations to this are:
-> increase the tx power of all nodes BEFOR UPDATING TO 1.5.13, even the
good ones with many neigborh to be sure not loosing contact to some poor
nodes!!!, I increased nodes from 5mW up to 20 mW and 20mW nodes up to 60mW.
After updateing to 1.5.13 you can change the power back depending on the
neighbors you see now with the mrate threshold.

  -so we have one node with a bad connection everytime, because of its in
room setup. After the update to 1.5.13, the node was lost and did not
reconnect after a couple of minutes. In this case, ssh to the best neighbor
of this unreachable node (you have to reminde its ip ;) and change its mrate
to auto (# wl mrate auto) & try to ssh to the unreachable node ... on my
side it took some minutes till i got the node. and than  change the nodes
radio setup to a better one, new antenna.. other lacation ... or increase
the txpower of this node as a quick´n dirty workaround.

-there is a new recommendation in the "overview"-tab with say
rts-threshold=2345 ... I gues this is an error, becaus you can use or
not-use the rts/cts mechanism. To disable the rts/cts mechanism, the
rts-threshold should be greater than the cts-threshold and to enable the
rts/cts mechanism, rts<cts. To get the most performance I recommend using
CTS=2346 & RTS=2347!
And if you want to use RTS/CTS mechanism, the optimum RTS-threshold is 128
with CTS=2346 (not rts=2345)!!! My recommendation to you is disabling
rts/cts, because the capacty increase from theorathical maximum of
13MBit/sek with rts/cts, up to 27MBit/sek without rts/stc. And the latency
gets half, so your transmittiontime of a tcp ip paket with aknowledge speed
up from 830microseks to 400microseks.

-the new security featur of not been able to login to a nodes via wlan rigth
after flashing is bad... bad for my side. because i´m in the position of
centralized administration of all nodes. So changing all httpd.conf scripts
of all nodes to get this admin over wlan feature ...  I didnt recongized it
is as such one ;) ...  is really hard work.
to sven ola: I would prefer secure web login .. might be to big in flash I
could guess with https deamin .. but how would be a new NVRAM variable to
allow the owner of a node, to specify in web gui if and which network are
allowed to configure via wlan using web gui ?????????

That´s my impression of updating from today ... so I have still one thing to
say, just see my next thread ;)) ..

Bye Bluse

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