Datasheet

Cisco Preferred Architecture for
Midmarket Collaboration PAGE 9
Introduction
Cisco recommends always deploying redundant configurations to provide the highest availability for critical business
applications; however, a non-redundant Cisco BE 6000 server configuration may be deployed for organizations that do
not require full redundancy.
Note: Space is available on the second Cisco BE 6000 server for additional Cisco Unified Communications
applications.
High Availability
The Cisco PA for Midmarket Collaboration provides high availability for all deployed applications by means of the
underlying clustering mechanism present in all Cisco Unified Communications applications.
Clustering replicates the administration and configuration of deployed applications to backup instances of those
applications. If an instance of an application fails, Cisco Unified Communications services — such as endpoint
registration, call processing, messaging, business-to-business communication, and many others — continue to operate on
the remaining instance(s) of the application. This failover process is transparent to the users. In addition to clustering, the
Cisco PA for Midmarket Collaboration provides high availability through the use of redundant power supplies, network
connectivity, and disk arrays.
The one exception to this is the TMS solution of applications. In order for TMS to be fully redundant, an external SQL
database is required as well as the Large Deployment of TMS, TMSPE, and TMSXE. To keep costs low for midmarket
customers, the recommended deployment is a single instance of the TMS solution with an embedded SQL server.
Cisco Integrated Services Router
Cisco Integrated Services Routers (ISR) and Aggregation Services Routers (ASR) provide Wide Area Network (WAN) and
Cisco Unified Communications services in a single platform. In the Cisco PA for Midmarket Collaboration, the Cisco ISR
and ASR can provide the following functions (Figure 3):
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Media resources (MTP and transcoder) for Cisco Unified Communications Manager
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External connectivity to Internet
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IP routing and network services such as DHCP, DNS, NTP, and others
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Cisco Unified Survivable Remote Site Telephony (SRST) to support calls during WAN failures
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Voice gateway to the Public Switched Telephone Network (PSTN) or Cisco Unified Border Element (CUBE) for
Session Initiation Protocol (SIP) trunks
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Integrated data and voice connectivity to service providers
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Multiprotocol Label Switching (MPLS) WAN connectivity for an organization’s network
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Virtual Private Network (VPN) client to establish secure tunnels to the VPN concentrator