Clearspan® Product Overview R19
Aastra – 2740-007
2014 Clearspan® is a Registered Trademark of Aastra Technologies Ltd.
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Database Server (DBS)
– provides database and call center reporting. Deployed in high-
availability configuration.
VoIP Monitoring
– an optional application to monitor and report on MOS scoring problems.
Billing
– an optional application to manage call detail records and user accounting.
In certain cases, Clearspan applications may be installed on discreet servers rather than within the
BladeCenter chassis in order to address specific issues with scalability, or redundancy, or to
address specific physical deployment requirements.
2.1.2
Detailed Server Descriptions
The following section will describe the server complex in detail and illustrate the main interconnect
and protocols used.
2.1.2.1
SIP Session Management (SSM)
The SSM servers are Session Border Controllers (SBCs) that are the secure (SIP/RTP) gateways
to the system. In the Clearspan architecture, all endpoints are “untrusted” and must traverse the
SSMs to gain access to the platform. The figure below shows the SSMs.
Figure 4. SSM Platform Interaction.
The SSMs are deployed as high-availability clusters and their purposes are:
VoIP/SIP firewall
SIP session security management
NAT traversal
Topology hiding
DoS and intrusion prevention
Header manipulation
Registration proxy
The SSMs participate in the registration and authentication of all endpoints, whether those
endpoints reside in the LAN or WAN. As endpoints register with the Clearspan platform, the SSMs
filter and check these registrations to prevent unauthorized access. Assuming the first phase of
filtering is passed, the registrations are then passed to the AS for authentication, and the SSMs
