Hello,
I'm currently working with OpenWrt using very often the OCB mode for wireless networks, together with the "iw dev ocb leave" and "iw dev ocb join 10MHz" commands, from the "iw" utility.
I recentely flashed the new 18.06.1 version of OpenWrt (after doing some personalization and building myself the firmware) on the memory of the boards I'm using and I noticed that, with respect to iw-4.9, these two commands were gone and I could not use them anymore.
Looking at the recent updates to the OpenWrt code, I found out that there was a patch "200-reduce_size.patch" (in package/network/utils/iw/patches/ - GitHub link) which was updated to change the package Makefile, adding, among other things, the following two lines:
These lines were actually excluding the ocb module from the build process, if I understood correctly, thus disabling the two commands mentioned before.
I solved the problem by creating another patch changing the first line to:
OBJS_DISABLED = offch cqm wowlan coalesce roc p2p ap
I still do not understand why this change has been introduced in the newer OpenWrt and iw versions. Do you know what is the purpose of the "200-reduce_size.patch" and why the ocb object file was excluded from build?
Thanks!
I have read the whole article and that could probably be the reason. Enabling the OCB options again by changing the patch seems to work correctly, by the way!
Personally, I'm not familiar with what the applications of OCB mode are. (Erroneous link removed)
If you think that it would be generally valuable, you might want to consider a patch or the suggestion of a iw-ocb and/or iw-full package for others that would need that functionality.
In reality, with "OCB" I was meaning the Outside Context of a BSS mode for wireless networks, not the "Offset Codebook Mode".
It is actually used when researching with Intelligent Transport Systems (ITS) and 802.11p systems, which require direct communication between devices and it is established by IEEE 802.11-2016 standard.
I don't know really if it has other applications outside the ITS ones, and if it is actually used outside the 802.11p frequency range for vehicular communications.
I am not so pratical here in the forums; what should I do to make an "official" suggestion for a full iw package? Should I write it as a low priority issue here?