Cisco Cisco Agent Desktop 8.5

The VoIP Monitor service also sniffs the network for voice packets, but it relies 
on the Switched Port Analyzer (SPAN) feature of the Cisco Catalyst line of 
switches to enable it to see the voice traffic for devices assigned to it. 

SPAN allows one or more ports or VLANs to be designated as source ports 
and a single port to be designated as the destination port. 

Source ports are any or all of the following:

Ports used to connect IP phones to the switch

Port used to connect the CallManager to the switch

Port used by the voice gateway

VLAN consisting of all the ports to be monitored by SPAN

The destination port is the port used to connect the VoIP Monitor service to the 
switch. 

Once SPAN is properly configured, all network traffic traversing the source 
ports is copied and sent to the destination port. In this way, the VoIP Monitor 
service can see all the voice traffic to the IP phones and is able to capture voice 
streams from a particular agent's device for silent monitoring or recording.

Some Catalyst switches have the Remote SPAN (RSPAN) advanced feature, 
which enables the VoIP Monitor service connected to one switch to see the 
voice traffic of a port on another Catalyst switch.

A VoIP Monitor service is limited in the number of calls it can monitor simulta-
neously. This is due to the speed of the server on which the service runs and on 
the speed of the network that delivers packets to it. 

For a contact center that has more agents than can be monitored by a single 
VoIP Monitor service, additional VoIP Monitor services can be installed. Each of 
these services is referred to as a monitor domain, and represents a pool of 
monitoring resources that can be assigned to monitor particular IP phones. 
Each VoIP Monitor service requires its own SPAN configuration on the switch 
to which it is connected.

Remote agents and supervisors are connected to the contact center’s local 
network via a wide area network (WAN) or virtual private network (VPN).