Bug 2921

Summary:	Add MIN_CWND variable in LEDBAT to align with RFC 6817
Product:	ns-3	Reporter:	Viyom Mittal <viyommittal>
Component:	tcp	Assignee:	natale.patriciello
Status:	RESOLVED FIXED
Severity:	normal	CC:	ns-bugs, tahiliani.nitk
Priority:	P3
Version:	ns-3-dev
Hardware:	All
OS:	All
Attachments:	Patch for Ledbat issue

Description Viyom Mittal 2018-05-30 02:02:23 UTC

Created attachment 3099 [details]
Patch for Ledbat issue

A variable MIN_CWND mentioned in the RFC 6817 has not been used in the LEDBAT implementation of ns-3. 

Adding this variable is important otherwise the assert condition NS_ASSERT (m_sentList.size () > 1) in tcp-tx-buffer fails. In addition, it is better to align the implementation with RFC.

This was observed while porting the AQM Evaluation Suite to work with latest ns-3-dev.

The attached patch fixes this issue.

An example to reproduce this issue is made available here:
https://github.com/ShefaliGups11/AQM-Evaluation-Suite/blob/Ledbat-Issue-Replication-Example/scratch/ledbat_issue.cc

Thanks,
Shefali
Viyom

Comment 1 natale.patriciello 2018-06-01 17:49:08 UTC

I feel fine with the patch. Please, since you're here initialize the member variables as in C++11 (in the header file) and remove the initializations from the constructor.

Please put the two patches on top of a branch and send me the link, I will apply them.

Nat

Comment 2 Viyom Mittal 2018-06-04 08:16:34 UTC

Hello Natale,

We have applied the two patches on the latest dev.

The commits can be found here:
https://github.com/ShefaliGups11/ns-3-dev-git/tree/Bug-2921-fix

Please use "ShefaliGups11" as the commit author and let us know if anything else is required.

Thanks,
Shefali
Viyom

Comment 3 natale.patriciello 2018-06-04 15:08:08 UTC

pushed in 13621:a0aa1022070a, thanks