Can you
hear me?
Case | Silent Calls
Starting Point | Major client escalation
person on other end of call can’t hear me
person on other end of call can’t hear me
person on other end of call can’t hear me
person on other end of call can’t hear me
person on other end of call can’t hear me
person on other end of call can’t hear me
person on other end of call can’t hear me
person on other end of call can’t hear me
person on other end of call can’t hear me
/excerpt of a 3 months log
Dec 10
Dec 11
Dec 12
Dec 13
Dec 16
Dec 17
Dec 18
Dec 19
Dec 20
VOIPFUTURE /// SILENT CALLS
1x
2x
-1x
4x
1x
3x
1x
1x
2
Triggered Activities
1
Task force
established
4
2
Software
checked
>
3
Hardware
checked
!
No results!
4 Months of
work
VOIPFUTURE /// SILENT CALLS
3
Next try | “Couldn’t we use the Voipfuture stuff?”
4h
Time required to understand the problem
VOIPFUTURE /// SILENT CALLS
4
Voipfuture monitoring revealed | Receiver chooses to play a zombie stream
Voice
Silence
Cause:
– Two RTP streams arrive
– Streams from previous calls were closed improperly
– Open streams carrying silence remain in
the network for weeks or months
Reason behind: Bug in call manager
VOIPFUTURE /// SILENT CALLS
5
The GUI view | Hunting the zombie
Two different streams simultaniously arrive at one receiver
VOIPFUTURE /// SILENT CALLS
6
Another example | Multi-national VoIP service for global clients
A
SBC
B
Call setup with two call legs
– Many tickets for silent calls and dropped calls.
– Linkage between problems not understood.
VOIPFUTURE /// SILENT CALLS
7
Voipfuture monitoring insight | Burst loss of 20 RTP packets
A
SBC
B
Impact:
– Packet loss triggers termination of one call leg.
– The other call leg remains active.
VOIPFUTURE /// SILENT CALLS
8
Required monitoring capabilities
All RTP
streams
Full
traffic
Both call
directions
VOIPFUTURE /// SILENT CALLS
5-second
time slices
Network
segementation
9
Thank you for your attention
VOIPFUTURE /// SILENT CALLS
10
Wendenstr. 4
20097 Hamburg
Germany
Tel: +49 40 688 900 10
Fax:+49 40 688 900 199
[email protected]
www.voipfuture.com
VOIPFUTURE /// SILENT CALLS
11