Bug 2654

Summary:	Rraa wifi manager cannot be used with 802.11b
Product:	ns-3	Reporter:	sebastien.deronne
Component:	wifi	Assignee:	Matías Richart <matis18>
Status:	RESOLVED FIXED
Severity:	minor	CC:	matis18, ns-bugs, tomh
Priority:	P3
Version:	ns-3.26
Hardware:	All
OS:	All
Attachments:	Patch to fix Patch to fix Change name of struct Thresholds in RrpaaWifiManager to avoid future conflicts

Description sebastien.deronne 2017-02-10 04:27:25 UTC

Testing 802.11b with Rraa ...
assert failed. cond="false", msg="Thresholds for an unknown mode are asked (DsssRate11Mbps)", file=../src/wifi/model/rraa-wifi-manager.cc, line=501
libc++abi.dylib: terminating

Either this manager should be extended for 802.11b, either we should trigger immediately an assert that rraa does not support 802.11b, similarly to what we have for HT/VHT/HE. I guess same issue is also encountered in 802.11g.

Comment 1 sebastien.deronne 2017-02-10 04:28:09 UTC

Info needed from Matias and/or Tom obout the preferred option.

Comment 2 Matías Richart 2017-02-10 10:46:29 UTC

(In reply to sebastien.deronne from comment #1)
> Info needed from Matias and/or Tom obout the preferred option.

I can extend it. I'll do it for next week.

Comment 3 sebastien.deronne 2017-02-10 10:58:41 UTC

(In reply to Matías Richart from comment #2)
> (In reply to sebastien.deronne from comment #1)
> > Info needed from Matias and/or Tom obout the preferred option.
> 
> I can extend it. I'll do it for next week.

Thanks, I will assign this to you.

Comment 4 sebastien.deronne 2017-02-12 03:32:05 UTC

FYI, it fails for 802.11b, 802.11-10MHz and 802.11-5MHz.

Comment 5 Matías Richart 2017-02-14 15:04:23 UTC

Created attachment 2785 [details]
Patch to fix

Current implementation of RRAA uses fixed values for ORI and MTL parameters. The values are taken from the table provided in the paper: http://svn.camrdale.org/school/papers/802.11lans.pdf which only considers 802.11a.

My patch proposes to calculate those values at initialization, following the guidelines proposed in the same paper.

There is a slight difference between the values of the table and the calculated values. This is because the paper does not clarify the exact values for the different parameters that are used in the calculations (e.g. frame length).

I also improve naming of variables, comments and logging.

Comment 6 sebastien.deronne 2017-02-15 14:53:59 UTC

Thanks Matias. Is the initial author still involved in ns-3? If yes, I suggest he reviews your patch.

Comment 7 Matías Richart 2017-02-15 16:34:20 UTC

(In reply to sebastien.deronne from comment #6)
> Thanks Matias. Is the initial author still involved in ns-3? If yes, I
> suggest he reviews your patch.

No, he isn't.

Comment 8 sebastien.deronne 2017-02-17 02:45:15 UTC

Then if it works fine I suggest to deliver.

Comment 9 sebastien.deronne 2017-02-20 14:24:41 UTC

I have some merge conflicts, could you have a look?
I cannot handle this error:
./ns3/rrpaa-wifi-manager.h:54:8: error: redefinition of 'Thresholds'
struct Thresholds

Comment 10 Tom Henderson 2017-02-20 14:56:48 UTC

(In reply to sebastien.deronne from comment #9)
> I have some merge conflicts, could you have a look?
> I cannot handle this error:
> ./ns3/rrpaa-wifi-manager.h:54:8: error: redefinition of 'Thresholds'
> struct Thresholds

Matias, while you are at it, can you please rename Thresholds to something more specific such as RraaThresholds or WifiRraaThresholds, or else move it into the class, because Thresholds is a somewhat generic name to put into namespace ns3?

Comment 11 sebastien.deronne 2017-02-28 16:01:39 UTC

Matias, any update on this?
I think the patch is almost ready.

Comment 12 Matías Richart 2017-02-28 17:46:21 UTC

(In reply to sebastien.deronne from comment #11)
> Matias, any update on this?
> I think the patch is almost ready.


Sorry for that, I didn't have RRPAA merged when testing the patch.
I uploaded the updated patch. 

I also propose to change the name of Thresholds in Rrpaa to avoid any troubles in the future.

Comment 13 Matías Richart 2017-02-28 17:46:50 UTC

Created attachment 2787 [details]
Patch to fix

Comment 14 Matías Richart 2017-02-28 17:47:31 UTC

Created attachment 2788 [details]
Change name of struct Thresholds in RrpaaWifiManager to avoid future conflicts

Comment 15 sebastien.deronne 2017-03-01 15:17:45 UTC

Thanks Matias, it is working fine.
I will deliver your changes.

Comment 16 sebastien.deronne 2017-03-01 16:21:01 UTC

Fixed in changeset 12724:74b99de24416