Live Key Rotation

It is possible to use Virtual Channel to support more kinds of key rotation than are currently possible with Unified Origin, for example creating a multi-period DASH output with frequently rotating keys.

It is done by scheduling transitions between sources, which can be otherwise identical, that use different DRM settings and encryption keys. This works with both Live and VOD sources, but the mechanism is slightly different for each.

For VOD2Live sources the DRM settings are included in the SMIL playlist <head>, so scheduling a change to a new key is as simple as sending a new SMIL playlist with different DRM options.

For Live sources however, because the encryption is handled by the source Live Origin, the new DRM needs to be configured at the source. This can be done by creating multiple output .isml files on the Live Origin with different DRM settings, and then scheduling transitions between them in Virtual Channel.