Quick means to measure quality of SIP / VoIP call without installing complex software solutions with comprehensive system configuration.

1. Copyright © Sevana Oü, 2019
Sevana Oü
Roosikrantsi tn 2
Tallinna linn, Harju maakond, 10119
Estonia
Phone: +3726170331
QualTest SIP
Document objectives.
This document describes application purpose, requirements, software architecture and user operations for
QualTest command line utility from Sevana Ou.
Application purpose.
Application purpose is to provide quick way to measure quality of SIP/VoIP call without installing complex
software solutions with comprehensive system configuration. Measuring is based on Sevana waveform
analysis technology and network statistics.
Hardware requirements.
CPU
Any x86/x64 Intel/AMD CPU from last 10-15 years. Low-end VPS are able to run the
application too.
Memory 256 MB system will be able to run tests.
I/O subsystem Not critical. Almost all processing is made in memory (except for on demand log file
saving).
Software requirements.
Software requirements are typical - Linux (including ARM builds) / macOS / Windows. Utility distribution
includes Python 3 scripts used to run with SIP/RTP pjsua command line softphone.
Utility does not depend on database connection (although it is possible to integrate it).
Operation model.
The application is a console utility. There are few modes of work:

2. Copyright © Sevana Oü, 2019
Sevana Oü
Roosikrantsi tn 2
Tallinna linn, Harju maakond, 10119
Estonia
Phone: +3726170331
- single call to SIP target. Utility will make a call and analyze incoming audio. Result will be printed to
console in JSON format.
- answering machine. Utility will wait for incoming call and play reference audio into it.
- single call to SIP target and send results to specified email.
- single call to SIP target and upload results to backend.
- connect to backend, load test settings, schedule and run as a daemon.
It is possible to set thresholds which will trigger sending the reports.
No specific data structures are used - everything is represented as plain text and audio files.
Application Architecture Model.
Configured application includes few components – controller, waveform analysis utilities and pjsua utility.
Supported codecs are:
- iLBC
- G711
- GSM
- G722
- OPUS
- G729
More codecs are available upon request.
Call quality analyzer calculates MOS value in two different ways:
● Using Sevana PVQA analyzer. Sevana single-ended (no reference audio required) waveform analysis
algorithm provides reasonable MOS value estimation based on impairments analysis. Please find
more details at: http://sevana.biz/products/pvqa/
● Using Sevana AQuA analyzer. This is end-to-end approach that requires reference audio to be
available during the test. Reference audio can be pre-recorded .wav file (uncompressed PCM) or
even outgoing audio stream (if calling to echo number).
Configuration of the utility is made from command line. Available parameters are listed in the table below:
Parameter name Parameter description Remarks
target SIP address to call. Can be sip: or sips: address or Optional parameter.

3. Copyright © Sevana Oü, 2019
Sevana Oü
Roosikrantsi tn 2
Tallinna linn, Harju maakond, 10119
Estonia
Phone: +3726170331
even does not include schema (sips: will be used in
such case)
Example is <sip:voice@mydomain.com>
Utility will wait for
incoming call if target is
not specified.
server
URL of backend server. Quality reports can be
uploaded to this server.
Optional. Default value is
blank - no backend used.
instance
Instance ID used when uploading to server.
Mandatory if --server
parameter is set. Usually
it is phone or softphone
name.
username SIP username. Mandatory.
password
SIP password.
Mandatory.
domain
Domain name of registrar PBX.
May contain port number.
Mandatory.
verbose
Be verbose. QualTest SIP will dump to console
more information.
Optional parameter.
verbose-pjsua Show pjsua output. Optional parameter.
email-to Email address to send quality report after test. Optional parameter.
email-from Email address used as source of quality reports. Optional parameter.
email-server SMTP server hostname. Optional parameter.
email-user SMTP username. Optional parameter.
email-password SMTP password.
reference-file Path to AQuA reference audio file. Optional parameter.
mos-pvqa-
threshold
PVQA MOS value threshold.
Optional parameter.
Default value is 5.0 - it
means all quality reports
will be sent / emailed.
mos-aqua-
threshold
AQuA MOS value threshold.
Optional parameter.
Default value is 5.0 - it
means all quality reports
will be sent / emailed.

4. Copyright © Sevana Oü, 2019
Sevana Oü
Roosikrantsi tn 2
Tallinna linn, Harju maakond, 10119
Estonia
Phone: +3726170331
daemon
Use daemon mode. Requires --server & --instance
to be set.
Optional parameter.
Here is example of output statistics on console:
{
"call_time": 31,
"conn_time": 267,
"duration": 31,
"endtime": 1546437639,
"id": "ca610f76-0e96-11e9-a055-94de80b0357e",
"instance": null,
"jitter_avg": "0.523",
"mos_aqua": 3.95,
"mos_pvqa": 2.565617,
"packet_counter": "1.5Kpkt",
"packet_discrd": "0",
"packet_dup": "0",
"packet_loss": "0",
"packet_reord": "0",
"percents_aqua": 96.77,
"rtt_avg": "0.194",
"srtp_status": "Active",
"srtp_suite": "AES_256_CM_HMAC_SHA1_80",
"target": "sips:voip_002@voipobjects.com"
}
Call characteristics in JSON report are:
Name Description
call_time Duration of call in seconds.
mos_pvqa MOS value computed by PVQA analyzer.
mos_aqua MOS value computed by AQuA analyzer.
conn_time SIP connection time in milliseconds.
end_time Time of call finish - it is UTC UNIX timestamp.

5. Copyright © Sevana Oü, 2019
Sevana Oü
Roosikrantsi tn 2
Tallinna linn, Harju maakond, 10119
Estonia
Phone: +3726170331
instance Instance ID from --instance parameter value.
jitter_avg Jitter in milliseconds.
packet_counter Number of RTP packets
target SIP address of remote peer.
packet_discrd Number of discarded RTP packets.
packet_dup Number of duplicated RTP packets.
packet_loss Number of lost RTP packets.
packet_reord Number of reordered RTP packets.
rtt_avg RTT average time (in milliseconds)
To get MOS from PVQA analyzer pvqa-caller needs pvqa.lic & pvqa.cfg files, which are software license
and configuration for PVQA analyzer.
For active tests (which rely on AQuA analyzer) aqua.lic file is needed.