Alcatel-Lucent 7330 Product Information Manual page 202

5 — VoIP overview
5.1 Overview
This chapter provides information about the implementation of the Voice over IP
(VoIP) service.
VoIP service operation modes
The system provides different modes of operation for VoIP services. These include
voice gateway, H.248 softswitch, and session initiation protocol (SIP) modes.
Voice gateway mode
When the service provider uses existing Class 5 switch for voice services, the system
uses the G6 voice gateway to interact with the switch and perform loop emulation.
The G6 voice gateway performs both the signaling and the bearer path end-point
functions.
H.248 softswitch mode
When the service provider uses the broadband data network for voice services, the
system interacts with the network through the ITU-defined H.248 protocol or the
IETF-defined Megaco protocol to an H.248-based softswitch. In this mode, the voice
traffic and signaling may follow different paths through the network.
SIP modes
When the service provider uses SIP for VoIP services, the system interoperates in
two SIP modes: SIP mode 1 or 'thin client' mode, and SIP mode 2 or 'thick client'
mode. Package D ONTs only support SIP mode 2.
When configuring SIP using OMCIv2 via TL1 or CLI, the Softswitch parameter
identifies the SIP gateway softswitch vendor. The format is four ASCII coded
alphabetic characters [A..Z] as defined in [ATIS-0322000]. A value of four null
characters indicates no particular vendor.
Starting in Release 04.02.02, the setting of this Softswitch parameter signals to the
ONT to use various types of SIP. Until all softswitch vendor IDs are identified,
package A, B, and H ONTs interpret some specific settings as follows:
•
THIN = legacy SIP 1 - Mode 1 SIP - thin client
•
any other setting including null = legacy SIP 2 - Mode 2 SIP - thick client
In these modes of operation, the ONT performs user agent functionality. The two
modes of operation are to allow for different signaling behavior, especially for
advanced call features, to be handled correctly for the two very different signaling
characteristics.
The ONT provides special functionality for emergency calls (911) originating at the
ONT including blocking ONT software upgrades when a 911 call is in progress. This
special functionality is not supported in package D ONTs.
5-2 March 2011 Alcatel-Lucent 7330/7302 ISAM FTTN R04.02.42a
ONT Product Information Guide Edition 01 3FE 54199 AAAA TCZZA