Cisco Cisco Agent Desktop 8.5 Guia De Configuração Rápida
Configuring and Troubleshooting VoIP Monitoring
36
November 2013
Assume that the three IP phones, each connect to a port on a different switch and are
all part of voice VLAN 100. The VoIP Monitor server is connected to switch 1. SPAN is
configured on switch 1 to copy all the network traffic for the devices in VLAN 100 to
the port connecting the VoIP Monitor server.
all part of voice VLAN 100. The VoIP Monitor server is connected to switch 1. SPAN is
configured on switch 1 to copy all the network traffic for the devices in VLAN 100 to
the port connecting the VoIP Monitor server.
If phone 3 calls phone 2, the voice traffic flows between the devices and switch 2 and
switch 3. Since this traffic does not go through switch 1, the VoIP monitor server does
not see that audio traffic.
switch 3. Since this traffic does not go through switch 1, the VoIP monitor server does
not see that audio traffic.
If phone 3 calls phone 1, the VoIP Monitor server sees the audio traffic for phone 3
because the traffic flows through switch 1 to get to phone 1.
because the traffic flows through switch 1 to get to phone 1.
traffic flows:
1. from the remote phone through the network cloud to a voice gateway
2. through switches 1, 2, and 3, and finally
3. to phone 3.
Audio packets leaving phone 3 take the reverse route. Since the audio packets
traverse switch 1, the VoIP Monitor server sees the audio packets for phone 3.
traverse switch 1, the VoIP Monitor server sees the audio packets for phone 3.
For some switches, there is a requirement that the SPAN destination port be a
member of the same VLAN as the source ports of the SPAN configuration. These
switches are shown in
member of the same VLAN as the source ports of the SPAN configuration. These
switches are shown in
.
Port Traffic Direction
Issue: Some SPAN configurations lead to duplicate streams and bad audio quality.
There is a subtle issue that is exposed in the example above when phone 3 and phone
1 are on a call with each other. Since both phones are part of the same VLAN, and
that VLAN is a source for the SPAN session, the VoIP Monitor server receives duplicate
audio packets, which results in very poor audio quality.
1 are on a call with each other. Since both phones are part of the same VLAN, and
that VLAN is a source for the SPAN session, the VoIP Monitor server receives duplicate
audio packets, which results in very poor audio quality.
By default, when a switch port is configured as a SPAN source port, the SPAN session
copies all the packets going to and coming from that port to the SPAN destination
port. This is not always the desired behavior. When you have two agent devices that
are part of the same SPAN configuration on a call with each other, and their call is
recorded or monitored, the resulting audio quality is very bad. The agent voices sound
slow and slurred. This is because the VoIP Monitor service is seeing each audio
packet twice.
copies all the packets going to and coming from that port to the SPAN destination
port. This is not always the desired behavior. When you have two agent devices that
are part of the same SPAN configuration on a call with each other, and their call is
recorded or monitored, the resulting audio quality is very bad. The agent voices sound
slow and slurred. This is because the VoIP Monitor service is seeing each audio
packet twice.