1. ACLI Configuration Guide
  2. Local Media Playback
  3. Media Setup and Playback

Media Setup and Playback

For each session requiring media playback, the Oracle® Enterprise Session Border Controller (E-SBC) sets up media that supports standard RTP parameters. From the original media (if present), the E-SBC preserves the synchronization source (SSRC), timestamp, and sequence number.

Media playback differs between configuration methods:

  • When configured with ACLI only, the playback duration is always continuous, meaning that the media file loops if it fails to cover the entire playback period. (ACLI configuration does not provide for playback-on-header.)
  • When configured with SPL, the playback duration is continuous except when using the playback-on-header option. The playback duration for the playback on header scenario changes according to the settings in the P-Acme-Playback header. This header contains a duration=<ms-value|once|continuous> value, so you can customize the playback duration.

    Playback timing options via playback on header include:

    • Continuous—Media playback continues until the point at which the playback scenario defines its stop; media file loops if it fails to cover the entire playback duration.
    • Once—The file plays until either the playback scenario defines its stop or until the media file runs out.
    • Ms-value—Playback continues for a specific duration (in milliseconds) and will loop if necessary.

Media Spirals

Certain call flows cause media to traverse the Oracle® Enterprise Session Border Controller multiple times, resulting in media spirals. For local playback, this means that multiple playback files can be triggered to play. In situations like this, the Oracle® Enterprise Session Border Controller uses the playback closest to the endpoint receiving the media playback. Origination A in the diagram below is played Local playback #1, even though the scenario also triggers Local playback #2.

The ESBC supporting playback during media spirals.

Media Files

Media files of ringback tones are uploaded to /code/media to the E-SBC. This file differs based on your media generation method and must be raw media binary. For Transcoding based RBT, ensure that the files RAW PCM 16-bit MONO samples, sampled at 8-khz encapsulated with little-endian formatting and cannot exceed 4.8 MB.

When using the SPL method:

  • A separate file is required for each different codec type, even if the media itself is the same.
  • Your configuration must specify a playback rate in bytes per second, as this setting defines how many bytes of data per unit of ptime are needed.
  • To preserve system memory resources, media files are limited to 2MB.

No media file can not exceed 5 minutes of playback data.