R2 Network Services Unit; Citellink Gateway - Mitel 3300 General Information Manual

3300 ICP General Information Guide
The Universal NSU connects to a 3300 ICP Controller through a fiber cable. Additional digital
trunk capacity can be added to the 3300 ICP by chaining two NSUs together via the Copper
Interface Module (CIM) connection, on the back of the NSU, using a Category 5 crossover cable.

R2 Network Services Unit

R2 is a protocol converter that allows the R2 NSU to access an R2 National Public Switched
Telephone Network (PSTN) using MF-R2 digital trunk signaling. The 3300 Controller also
receives and processes Calling Line Identification (CLI) and allows the information to be
displayed on the user's telephone display screen.
The R2 NSU supports the CCITT Blue Book, Volume VI, Fascicle VI.4, Specifications of
Signaling System R2, Recommendations Q.440 to Q.490 (with the exception of Echo
Suppression (Q.479), Test Calls (Q.490) and international signals).
The R2 NSU converts the following:
• Incoming MF-R2 signals from the PSTN into Digital Private Network Signaling System
(DPNSS) signals for the system
• Outgoing DPNSS signals from the system into MF-R2 signals for the PSTN

CITELlink Gateway

The CITELlink Gateway allows the 3300 ICP controller to support legacy Nortel Networks™
Meridian 1 and Norstar telephone sets. The gateway translates the 3300 ICP IP phone protocol
to Norstar set protocol allowing Norstar and Meridian 1 phones to function as Mitel IP phones.
There are different versions of the CITELlink Gateway, according to the phone types supported.
The CITELlink Gateway provides an easy migration path to IP for Norstar and Meridian 1
customers by allowing Norstar and Meridian 1 phones to be redeployed on a 3300 ICP. This
allows organizations to retain legacy phone sets and existing wiring, minimize user disruption,
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