Re: ath10k to ath9k IBSS, ath9k has interface-combinations issue

[Sven-Ola Tuecke <sven-ola@gmx.de>]

[-- Attachment #1: Type: text/plain, Size: 1176 bytes --]

Am 08.04.2015 um 05:25 schrieb Sujith Manoharan:
> TSF would jump around since the HW would sync with the
> received beacons and this will happen in both IBSS and station
> mode. Hence the limitation, but I think OpenWrt has a one-liner
> to remove this restriction...
TSF in larger IBSS meshes (> 100 nodes) may be jumpy anyway, e.g. it
requires only one (misonfigured / buggy) node to introduce a TSF >
0xffffffff00000000 once. Because all IBSS nodes will take over the
largest TSF unverified from any neighbour, you end up by having TSF
bouncing around 64 bit overflow until you switch off the mesh
completely. We had this situation a couple of years here in Berlin.
Moment, let's have a look:

-> Frame 2: 104 bytes on wire (832 bits), 104 bytes captured (832 bits)
-> Radiotap Header v0, Length 18
-> IEEE 802.11 Beacon frame, Flags: ........
+> IEEE 802.11 wireless LAN management frame
   +> Fixed parameters (12 bytes)
      +> Timestamp: 0x0008004c7ddf6095

Seems the familiar 0xffffffffxxxxxxxx TSF is gone for some reason. In
practise, this does not hurt too much, you get a second downtime every
hour or so on turnaround.

// Sven-Ola



[-- Attachment #2: OpenPGP digital signature --]
[-- Type: application/pgp-signature, Size: 181 bytes --]