[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:              2010-09-21 18:31 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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 (0127259) saltydog256 (reporter) - 2010-09-21 18:31
 https://issues.asterisk.org/view.php?id=17982#c127259 
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Tested the suggested 0018010 [patch] as a possible solution, but there was
no change.  The patched version still works on a SIP connection without
jitter buffers. Asterisk was restarted after the patch was applied.

I have changed Service Provider but this is a costly option and requires
all the alarms to be reprogrammed, many which cannot be done without a
visit. The use if jitter buffers is becoming more prevalent as ISPs shape
their bandwidth more - so a solution would have value.  Until recently it
has worked faultlessly for several years and is a good app. 

Issue History 
Date Modified    Username       Field                    Change               
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2010-09-21 18:31 saltydog256    Note Added: 0127259                          
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