What is Voice Over IP?
XN120 Voice Over IP Card Guide
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What is Voice Over IP (VoIP)?
Voice Over IP is a general term used to describe the transmission of voice over IP-based data networks. There
are several different VoIP protocols in use worldwide. The most recent protocol, and the protocol used by the
XN120, is called Session Initiation Protocol (SIP). SIP is defined by the Internet Engineering Task Force (see
http://www.ietf.org).
SIP Trunks can be used to connect the XN120 to other XN120 systems (or some other SIP-compliant
telephone systems). This allows calls to be made between the systems over existing data networks rather than
using the PSTN.
Note:
The are many issues that need to be considered before implementing VoIP and it is highly recommended that
you consult the “NEC Infrontia Voice Over IP Reference Manual” (991451-5) before attempting this.
XN120 VOIPU Cards Available
Each XN120 VOIPU card has 4 Digital Signal Processors (DSP) on board. Each DSP can handle one VoIP
call. There is also an optional 4 port daughterboard that can be installed onto the VOIPU to increase the
number of DSPs to 8.
The photograph below shows a 4VOIPU card with the 4VOIPUDB installed. The card provides 8 DSP
resources and therefore supports up to 8 simultaneous VoIP calls.
Note:
An EXIFU-A1 is also required for VoIP on the XN120. Please refer to the EXIFU Guide (991423-5) for further
information about this card
The VOIPU cards are installed in the 2OPBOX unit, refer to the guide supplied with the 2OPBOX for installation
instructions.
Each 20PBOX unit can have up to two VOIPU cards installed.
Compact Flash Socket
Debug Port
Do not use
Ethernet
port
Daughter-
Board
Boot Run/Blk Load Reset
