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--- systems:voip [2013/03/16 22:28] – superwizard
+++ systems:voip [2013/03/24 01:09] (current) – [why is the audio/video quality poor in one direction] superwizard
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 | Authorization ID | Authorization name |
+====== Recognizing and Categorizing Symptoms of Voice Quality Problems ======
+From: http://www.cisco.com/en/US/tech/tk652/tk698/technologies_white_paper09186a00801545e4.shtml
+    Introduction
+    High Level Troubleshooting Procedure
+    Categorize and Define the Symptoms
+    Sample Sound Recordings
+    Noise
+    Voice Distortion
+       Echoed Voice
+       Garbled Voice
+       Volume Distortion
+    Common Problems Hearing Sound Files
+    Cisco Support Community - Featured Conversations
+    Related Information
 ====== why is the audio/video quality poor in one direction ======
@@ Line 37: / Line 54: @@
 Network testing
-Soak testing is running a system at high levels of load for prolonged periods of time.  A soak test would normally execute several times more transactions in an entire day (or night) than would be expected in a busy day, to identify any performance problems that appear after a large number of transactions have been executed
+    Soak testing is running a system at high levels of load for prolonged periods of time.
+    A soak test would normally execute several times more transactions in an entire day (or night)
+    than would be expected in a busy day, to identify any performance problems that appear after a
+    large number of transactions have been executed.
+====== Packet Loss Testing ======
+From: http://packetloss.sourceforge.net/
+    Packetloss is a set of programs to detect packet losses in UDP and TCP between two hosts. It does
+    this by sending a continuous stream of packets, and detects any delay or loss in the streams. It is useful to measure the impact of failover tests
+====== Detecting IP Packet Loss for UberNerds ======
+From: http://www.onsip.com/blog/2007/10/25/detecting-ip-packet-loss-ubernerds
+   Now you might think someone would have a hard time hearing a 1/50 second gap in a 3 minute conversation.
+   And you would be right. But if there is an IP network in the middle of the conversation, it turns out that
+   drop detection depends greatly on the the piece of IP phone hardware/software one is talking on. In this case,
+   the Polycom IP phone on my desk was useless as an empirical tool in helping me track down the 0.05% packet loss
+   in question - I simply could not hear it. However, the Grandstream GXP-2000 (version 1.1.0.14) we have in our
+   test bed turned out to be an invaluable tool since it has the uncanny ability to turn the 1/50 second gap caused
+   by a single lost packet into a multi-second garbled mess. So, if like me, you enjoy testing for dropped packets,
+   I highly recommend adding the Grandstream to your toolbox - it is a great tool and worth far more than the retail price.