Cisco Cisco IP Contact Center Release 4.6.1 Leaflet
3-5
Cisco Unified Contact Center Enterprise 7.5 SRND
Chapter 3 Design Considerations for High Availability
Data Network Design Considerations
emphasizes the redundancy of the single site design in
. Side A and Side B are
basically mirror images of each other. In fact, one of the main Unified CCE features to enhance high
availability is its ability to add redundant/duplex components that are designed to automatically fail-over
and recover without any manual intervention. Core system components with redundant/duplex
components are interconnected to provide failure detection of the redundant/duplex system component
with the use of TCP keep-alive messages generated every 100 ms over a separate Private Network path.
The fault-tolerant design and failure detection/recovery method is described later in this chapter.
availability is its ability to add redundant/duplex components that are designed to automatically fail-over
and recover without any manual intervention. Core system components with redundant/duplex
components are interconnected to provide failure detection of the redundant/duplex system component
with the use of TCP keep-alive messages generated every 100 ms over a separate Private Network path.
The fault-tolerant design and failure detection/recovery method is described later in this chapter.
Other components in the solution use other types of redundancy strategies. For example, Cisco Unified
Communications Manager (Unified CM) uses a cluster design to provide IP phones and devices with
multiple Unified CM subscribers (servers) with which to register if the primary server fails, and those
devices automatically re-home to the primary when it is restored.
Communications Manager (Unified CM) uses a cluster design to provide IP phones and devices with
multiple Unified CM subscribers (servers) with which to register if the primary server fails, and those
devices automatically re-home to the primary when it is restored.
The following sections use
as the model design to discuss issues and features that you should
consider when designing Unified CCE for high availability. These sections use a bottom-up model (from
a network model perspective, starting with the physical layer first) that divides the design into segments
that can be deployed in separate stages.
a network model perspective, starting with the physical layer first) that divides the design into segments
that can be deployed in separate stages.
Cisco recommends using only duplex (redundant) Unified CM, Unified IP IVR/Unified CVP, and
Unified ICM configurations for all Unified CCE deployments. This chapter assumes that the Unified
CCE failover feature is a critical requirement for all deployments, therefore it presents only deployments
that use a redundant (duplex) configuration, with each Unified CM cluster having at least one publisher
and one subscriber. Additionally, where possible, deployments should follow the best practice of having
no devices, call processing, or CTI Manager Services running on the Unified CM publisher.
Unified ICM configurations for all Unified CCE deployments. This chapter assumes that the Unified
CCE failover feature is a critical requirement for all deployments, therefore it presents only deployments
that use a redundant (duplex) configuration, with each Unified CM cluster having at least one publisher
and one subscriber. Additionally, where possible, deployments should follow the best practice of having
no devices, call processing, or CTI Manager Services running on the Unified CM publisher.
Data Network Design Considerations
The Unified CCE design shown in
illustrates the voice call path from the PSTN (public
switched telephone network) at the ingress voice gateway to the call reaching a Unified CCE agent. The
network infrastructure in the design supports the Unified CCE environment for data and voice traffic.
The network, including the PSTN, is the foundation for the Unified CCE solution. If the network is
poorly design to handle failures, then everything in the contact center is prone to failure because all the
servers and network devices depend on the network for highly available communications. Therefore, the
data and voice networks must be a primary part of your solution design and must be addressed in the
early stages for all Unified CCE implementations.
network infrastructure in the design supports the Unified CCE environment for data and voice traffic.
The network, including the PSTN, is the foundation for the Unified CCE solution. If the network is
poorly design to handle failures, then everything in the contact center is prone to failure because all the
servers and network devices depend on the network for highly available communications. Therefore, the
data and voice networks must be a primary part of your solution design and must be addressed in the
early stages for all Unified CCE implementations.
Note
Cisco recommends that the NIC card and ethernet switch be set to 100 MB full duplex for 10/100 links,
or set to auto-negotiate for gigabit links for all the Unified ICM core component servers.
or set to auto-negotiate for gigabit links for all the Unified ICM core component servers.
In addition, the choice of voice gateways for a deployment is critical because some protocols offer more
call resiliency than others. This chapter provides high-level information on how the voice gateways
should be configured for high availability with the Unified CCE solution.
call resiliency than others. This chapter provides high-level information on how the voice gateways
should be configured for high availability with the Unified CCE solution.
For more information on voice gateways and voice networks in general, refer to the Cisco Unified
Communications Solution Reference Network Design (SRND) guide, available at
Communications Solution Reference Network Design (SRND) guide, available at