Summary:	ASTERISK-28874: res_rtp_asterisk: RFC2833/RFC4733 Minimum signal duration not adhered to
Reporter:	Ross Beer (rossbeer)	Labels:
Date Opened:	2020-05-07 08:51:15	Date Closed:	2020-05-11 05:45:51
Priority:	Minor	Regression?	No
Status:	Closed/Complete	Components:	Resources/res_rtp_asterisk
Versions:	GIT 16.10.0 17.4.0	Frequency of Occurrence	Constant
Related Issues:
Environment:	CentOS 7.6	Attachments:
Description:	The minimum RFC2833/RFC4733 DTMF signal duration should be 40ms, however Asterisk processes packets with the duration less than this. Any packets less than 40ms should be discarded and therefore ignored when using the Read and Background applications.
Comments:	By: Asterisk Team (asteriskteam) 2020-05-07 08:51:16.943-0500 Thanks for creating a report! The issue has entered the triage process. That means the issue will wait in this status until a Bug Marshal has an opportunity to review the issue. Once the issue has been reviewed you will receive comments regarding the next steps towards resolution. A good first step is for you to review the [Asterisk Issue Guidelines|https://wiki.asterisk.org/wiki/display/AST/Asterisk+Issue+Guidelines] if you haven't already. The guidelines detail what is expected from an Asterisk issue report. Then, if you are submitting a patch, please review the [Patch Contribution Process|https://wiki.asterisk.org/wiki/display/AST/Patch+Contribution+Process]. Please note that once your issue enters an open state it has been accepted. As Asterisk is an open source project there is no guarantee or timeframe on when your issue will be looked into. If you need expedient resolution you will need to find and pay a suitable developer. Asking for an update on your issue will not yield any progress on it and will not result in a response. All updates are posted to the issue when they occur. By: Joshua C. Colp (jcolp) 2020-05-07 10:21:46.458-0500 What's a packet capture and console output for this? And does this result in DTMF duplication as-is right now? By: Ross Beer (rossbeer) 2020-05-07 10:50:47.590-0500 I have sent the PCAP over to you. We expect to only receive a single digit on the 'Background' application however it is receiving multiple inputs. The CLI shows the digits '11' in the invalid context as we are only expecting a single-digit [0-9] in the dial plan. By: Joshua C. Colp (jcolp) 2020-05-07 11:32:20.036-0500 Where in the RFC do you see the language about ignoring signal duration less than 40ms from the perspective of the out of band DTMF? It reads as though it is referring to the detection of the inband DTMF and conversion into out of band DTMF. By: Ross Beer (rossbeer) 2020-05-11 05:45:51.725-0500 The sending end needs to drop tones under 40ms and not the receiving end. Therefore this is not an issue.