Context
During the application of the fax service, the FoIP service can be classified into two modes
according to the participation of the SIP signaling in the transmission control process:
l
Self-switch: If the self-switch mode is configured, the fax working mode of the MA5616
needs to be configured manually.
l
Auto-negotiation: If the auto-negotiation mode is configured, the fax working mode of the
MA5616 needs to be configured manually.
The FoIP service can be classified into two modes according to the fax coding:
l
Transparent transmission fax: The voice encoding (G.7xx encoding) is adopted.
l
T.38 fax: The T.38 encoding is adopted.
The MA5616 supports the 10 ms packing function and the RFC 2198 function.
l
10 ms packing function: In addition to the 20 ms G.711 transparent transmission, the fax
transparent transmission function is added with the 10 ms G.711 transparent transmission.
This reduces delay, improves the performance of transparent transmission, and decreases
the impact of packet loss on the transmission of the modem service data.
l
RFC 2198 function: Through the redundant transmission, the RFC 2198 improves the
reliability of data transmission. When the network packet loss occurs, the RFC 2198 can
ensure the service quality.
Data preparation
It is recommended that you plan the working mode of the fax on the entire IP multimedia
subsystem (IMS) before configuring the data so that the working mode on the entire network is
consistent.
Table 7-29
Items involved in the FoIP service
Item
Option
Remarks
Codec
negotiation
mode
Negotiation
The codec mode needs to be negotiated through the SIP
signaling.
Self-switch
The MG determines what codec mode is used.
Codec mode Transparent
transmission fax
The G.711 encoding is adopted.
T.38 flow
The T.38 encoding is adopted.
Default Configuration
lists the default configuration of the flows of the FoIP service.
SmartAX MA5616 Multi-service Access Module
Configuration Guide
7 Configuring the Voice Service
Issue 04 (2011-10-30)
Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
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