Common media data¶
PRESTOplay implements the Common Media Data standards so the player can cooperate more closely with your content delivery network (CDN) infrastructure. This page explains the shared Common Media Client Data (CMCD, CTA-5004) and Common Media Server Data (CMSD, CTA-5006) concepts. Platform pages then cover SDK-specific configuration.
CMCD (Common Media Client Data)¶
See the CMCD specification (CTA-5004).
When CMCD is enabled, the player adds contextual playback metadata to every media request, such as buffer level, selected bitrate, or recent throughput. CDNs can use this metadata to prioritize requests, prefetch the next segment, or diagnose delivery issues.
CMSD (Common Media Server Data)¶
See the CMSD specification (CTA-5006).
CMSD defines a standard way for media servers — origin servers and CDN intermediaries — to return data with each media object response, such as estimated throughput or the next object to fetch. The player processes this data to improve delivery efficiency and the viewer’s quality of experience. Unlike CMCD, which travels from player to server on requests, CMSD travels from server to player in HTTP response headers.