iPECS UCP - 2.80 System Networking; 2.80.1 Centralized Control T-NET

iPECS UCP
Feature Description and Operation Manual Issue 1.3
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2.80 System Networking
2.80.1 Centralized Control T-NET
Description
In a Centralized Control T-NET (Transparent Network), a central iPECS UCP module
controls all remote modules and terminals providing transparent networked access to all the
features and functions of the central iPECS as well as the resources connected to the iPECS.
Where the remote device is not directly reachable by the iPECS, RTP packets must be
relayed through a local VoIP channel. A remote device may not be reachable when WAN
access for the device is through a firewall or NAPT server. In this case, the remote devices
are assigned a zone to manage RTP traffic between other devices connected in the T-NET.
The zone defines when an individual device requires use of a local VoIP channel. Zones are
used to identify other group characteristics as outlined in section 2.86.3.
Remote sites may include an iPECS UCP module operating in the local mode as a live back-
up to the remote central system. Under normal circumstances, the central UCP module
controls remote devices(gateway Modules and terminals) including any local UCP VoIP
channels. However, should the WAN connection between the central system and the remote
devices fail, the local UCP module will assume the call server responsibility for the local
devices. The local module thus provides local survivability and, based on configuration, may
provide PSTN back-up service (Fail-over)for internal calls that normally route over the WAN.
Under certain operating conditions, this equipment cannot be relied upon to make emergency
calls. Alternative arrangements should be made for access to the emergency services.
Operation
System
Conditions
Operation of Centralized Network is automatic when configured & defined.
1. In a Centralized Network, the maximum number of channels available is the
maximum number of channels supported by the central iPECS UCP.
2. In T-NET, Centralized Miscellaneous functions (Relay support, MOH, BGM,
Alarms and External Page) are not supported but, all terminals in the T-NET can
make and receive pages.
3. When NAPT or other firewall functions are implemented, packet relay for RTP
packets is required. Packet relay requires VoIP channels for each simultaneous
call desired.
4. The local UCP module will take over operation of registered devices if the central
controlling iPECS UCP does not respond to three consecutive poll attempts over a
10-second period. The central iPECS UCP module will gain control automatically