Nortel Nortel Passport 8100, Reference Manual, Page: 129 / 252

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infrastructure, while preserving their investment
in their existing systems
• ITG Trunk quickly IP-enables all existing Meridian
sets for site-to-site IP telephony traffic, while
seamlessly integrating with the PBX features and
functions. Customers can deploy multi-site IP
telephony without any user-retraining,
installation of poorly integrated (and high
administrative cost) external devices and still
have access to all of the PBX features and
functions they need for maximum flexibility
and efficiency
• ITG Trunk products also eliminate the worry of
doing a “forklift” upgrade and cut-over to a
different vendor’s completely different IP-based
system, that may have unknown missing
features, require user and administrator
re-training, and throw away the significant
investment made in telephone sets, etc. Instead,
ITG Trunk products allow IP trunking to be used
without having to replace all of the rest of the
installed infrastructure
Features and Benefits
The Meridian Internet Telephony Gateway (ITG)
system offers customers the ability to reduce their
communication costs by routing voice traffic at low
marginal cost over existing private IP network
facilities with available under-utilised bandwidth on
the intranet. By enabling organisations to send more
traffic over IP networks, costs are reduced as routing
through the PSTN is minimised.
The Meridian Internet Telephony Gateway (ITG)
product compresses Pulse Code Modulation (PCM)
voice, demodulates Group 3 fax and routes the
packetised data over a private intranet, to provide
non-ISDN tie trunks between Meridian 1 Electronic
Switched Network (ESN) nodes. It is a requirement
that the customer has already installed a corporate
IP network and that routers are available for WAN
connectivity between networked Meridian 1 systems.
ITG is offered for intranet, rather than Internet use,
since an intranet is a more controlled and managed
data environment. 100/10BaseT Ethernet interfaces
to the ITG card are required, as well as support of IP
version 4 Network layer and addressing in the WAN.
There is no restriction on the physical medium
of the WAN.
ITG Trunk cards are Intelligent Peripheral Equipment
(IPE) trunk cards that link two or more Meridian 1
systems together in a private IP WAN network. ITG
Trunk packetises and compresses voice and
modulates fax for transmission over customers’
IP WAN. They include an ISDN D-Channel to provide
enhanced signalling between Meridian 1 systems,
allowing them to be networked.
ITG Trunk uses ISDN protocols with H.323 signalling
and voice over a standard IP protocol stack. As
standards become well deployed, this will also
facilitate native communication between multiple
vendors’ IP based communication systems. ITG
Trunk cards monitor Quality of Service (QoS)
parameters across the data network (such as
latency, jitter and packet loss) to ensure that high
quality voice is delivered. If these measurements
exceed acceptable levels at call set-up, then calls are
automatically routed over traditional voice lines.
When the QoS parameters return to acceptable
levels, IP routing automatically resumes with the
next call. Operations, Administration, and
Maintenance (OAM) for Meridian ITG Trunk cards
can be performed using Optivity Telephony Manager
(OTM). Meridian 1 X11 Release 25 software is required.
The Meridian ITG Trunk provides the
following benefits:
• Enables ISDN trunk connectivity (similar to ISL –
ISDN Signalling Link) between Meridian 1
systems over an IP WAN
• Reduces communications and support costs
• Deploys easily in a Meridian 1 network
• Complies with standard codecs (G.711, G.723.1,
G.729B and G.729AB)
• Offers simple installation and maintenance
with OTM
• Builds on the reliability and feature-richness of
the Meridian 1 system
• Operates transparently to the end user when
routing over the IP data network
Internet Telephony Gateway (ITG) Trunk