Contents
1 Introduction
This document describes how to configure the P-Early-Media Interworking (PEM IWF) service in the MMTel AS.
1.1 Prerequisites
It is assumed that the user of this document is familiar with the Operation and Maintenance (O&M) area, in general.
1.1.1 Licenses
Not applicable.
1.1.2 Documents
Before starting any procedure in this document, ensure that the following documents are available:
1.1.3 Conditions
The following condition must apply:
- An Ericsson Command-Line Interface (ECLI) session in Exec mode is in progress.
2 Overview
The PEM Interworking service aims to adapt MTAS to solve interoperability problems when VoLTE devices are not required to support the SIP P-Early-Media header and associated functions.
The service is active when its administrative state is unlocked.
2.1 Interaction with Other Services
2.1.1 Flexible Communication Distribution
Gating function is required. If multiple early media is sent to caller early media, the user experience can be strange if there is network-provided early media.
2.1.2 Gateway Model
To avoid unnecessary triggering of the PEM Interworking service, when used with the Gateway Model (GM) service, the GM service must be configured to keep the PEM header, if supported by the originating user.
2.1.3 Charging
The Flexible AVP cannot be triggered on headers or any attributes of the incoming message, which is filtered out by the PEM Interworking service, because Interworking Functions cannot be executed after charging is received.
3 PEM Interworking Service Configuration
The PEM Interworking service is configured through the OAM interface and controlled by the MtasPemIwfManaged Object (MO) and its attributes. An overview of the MO structure is shown in Figure 1.
For configurable MOs and attributes related to the PEM Interworking service, refer to Managed Object Model (MOM).
3.1 PEM Interworking Administrative State Configuration
The PEM Interworking service is enabled by setting the mtasPemIwfAdministrativeState attribute in the MtasPemIwf MO to 1 (Unlocked).
If the mtasPemIwfAdministrativeState is set to 0 (Locked), no PEM Interworking is provided by the MMTel AS.
3.2 PEM Interworking Indication of Supported: 199
The attribute mtasPemIwf199SupportedIndication handles 199 Supported indication in forward INVITE.
If mtasPemIwf199SupportedIndication = 0 (Disabled), 199 Supported indication in forward INVITE is disabled.
If mtasPemIwf199SupportedIndication = 1 (Enabled), 199 Supported indication in forward INVITE is enabled.
4 Performance Management
Not applicable.
5 Fault Management
Not applicable.