Cisco Cisco Unified Contact Center Enterprise 9.0(2) Design Guide

routing and service control messages required to route voice calls to peripheral targets (such as 
agents, skill groups, or services) and other media termination resources (such as Unified IP IVR 
ports) as well as the real-time updates of peripheral resource status.

Data traffic

Data traffic can include normal traffic such as email, web activity, and CTI database application 
traffic sent to the agent desktops, such as screen pops and other priority data. Unified CCE priority 
data includes data associated with non-real-time system states, such as events involved in reporting 
and configuration updates.

This chapter focuses primarily on the types of data flows and bandwidth used between a remote 
Peripheral Gateway (PG) and the Unified ICM Central Controller (CC), on the network path between 
sides A and B of a PG or of the Central Controller, and on the CTI flows between the desktop application 
and CTI OS and/or Cisco Agent Desktop servers. Guidelines and examples are presented to help 
estimate required bandwidth and to help implement a prioritization scheme for these WAN segments.

The flows discussed encapsulate the latter two of the above three traffic groups. Because media (voice 
and video) streams are maintained primarily between Cisco Unified Communications Manager and its 
endpoints, voice and video provisioning is not addressed here.

For bandwidth estimates for the voice RTP stream generated by the calls to Unified CCE agents and the 
associated call control traffic generated by the various protocols, refer to the Cisco Unified 
Communications Solution Reference Network Design (SRND) guide, available at

Data traffic and other mission-critical traffic will vary according to the specific integration and 
deployment model used. For information on proper network design for data traffic, refer to the Cisco 
Enterprise QoS Solution Reference Network Design Guide, available at 

The fault-tolerant architecture employed by Unified CCE requires two independent communication 
networks. The private network (using a separate path) carries traffic necessary to maintain and restore 
synchronization between the systems and to allow clients of the Message Delivery Subsystem (MDS) to 
communicate. The public network carries traffic between each side of the synchronized system and 
foreign systems. The public network is also used as an alternate network by the fault-tolerance software 
to distinguish between node failures and network failures.

The terms public network and visible network are used interchangeably throughout this document.

A third network, the signaling access network, may be deployed in Unified ICM systems that also 
interface directly with the carrier network (PSTN) and that deploy the Hosted Unified ICM/Unified CCE 
architecture. The signaling access network is not addressed in this chapter.

 illustrates the fundamental network segments for a Unified CCE system with a duplexed PG 

and a duplexed Central Controller (with sides A and B geographically separated).