How many RTP streams exist on the network when a Cisco Unified Contact Center Express agent is engaged in a call that is being silently monitored and recorded?

6 RTP streams exist when UCCE agent is engaged in a call when it is being silently monitored.
Reference: http://www.cisco.com/en/US/docs/voice_ip_comm/cust_contact/contact_center/crs/express_9_0/design/UCCX_BK_UD5B347F_00_uccx-solution-reference-network-design_chapter_0110.html