[asterisk-bugs] [Asterisk 0017982]: ACK tone interupted - Jitterbuffers do not function properly as AlarmReceiver App does not send RTP regularly

[Asterisk Bug Tracker]

A NOTE has been added to this issue. 
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https://issues.asterisk.org/view.php?id=17982 
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Reported By:                saltydog256
Assigned To:                
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Project:                    Asterisk
Issue ID:                   17982
Category:                   Applications/app_alarmreceiver
Reproducibility:            always
Severity:                   minor
Priority:                   low
Status:                     acknowledged
Asterisk Version:           Addons-1.6.2.1 
JIRA:                       SWP-2195 
Regression:                 No 
Reviewboard Link:            
SVN Branch (only for SVN checkouts, not tarball releases): N/A 
SVN Revision (number only!):  
Request Review:              
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Date Submitted:             2010-09-12 04:08 CDT
Last Modified:              2011-04-06 18:43 CDT
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Summary:                    ACK tone interupted - Jitterbuffers do not function
properly as AlarmReceiver  App does not send RTP regularly
Description: 
The SIP service provider added jitterbuffers, and since then the Alarm does
not recognize the ACK tone.  Dialing manually and listening to the tone
ones hears an interruption (high speed stutter). The Alarm keeps resending
data until it times out.  Data is received correctly and the checksum is
good.

Wireshark was used to inspect a normal incoming voice SIP call - Asterisk
sends back 20mS RTP timestamps regularly and the voice is uninterrupted. 
When AlarmReceiver answers a call the RTP timestamps are erratic or
non-existent. The ACK tone is badly distorted (as the packets are not
assemble correctly by the jitterbuffers).

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Relationships       ID      Summary
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related to          0018010 [patch] ACK tone not reliable on embedd...
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 (0133484) jplord (reporter) - 2011-04-06 18:43
 https://issues.asterisk.org/view.php?id=17982#c133484 
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I started having this issue as a result of upgrading an old ATA to a newer
model. The ACK tone started to be interrupted as a result. I have done
extensive testing on this issue and the linked issue.

1. Made a change to the alarmreceiver app to use ast_generate_silence when
waiting for tones from the panel. The RTP flow was consistent with to and
from packets after this change, but the ACK tone kept being interrupted
with all ATAs and the Cisco phones I have.

2. I have done a retrofit of the patch in the linked issue into 1.4.40
replacing the sendtoneburst function with built in ast functions as done in
the above patch. This has fixed the ack tone !

Tested with my local DSC panel connected on LAN via my new and old ATAs.

Also tested with another panel connected to an ATA remotely - remote
asterisk - tun interface - IAX2 - asterisk with patched alarmreceiver.
Works perfect.

Can this bug be fixed into 1.4 

Issue History 
Date Modified    Username       Field                    Change               
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2011-04-06 18:43 jplord         Note Added: 0133484                          
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