diff --git a/index.bs b/index.bs index b0dc644..a7b9f94 100644 --- a/index.bs +++ b/index.bs @@ -1184,8 +1184,36 @@ spec: encrypted-media-draft; for: EME; urlPrefix: https://w3c.github.io/encrypte or APIs but is provides an easier access to some information that can be used to fingerprint users.

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+ Capabilities Model +

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+ This specification supports {{MediaDecodingType}} values of {{file}}, + {{media-source}} or {{webrtc}} as well as {{MediaEncodingType}} + values of {{record}} and {{webrtc}}. +

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+ In realtime communications as supported in [[webrtc]], media is + transported between peers. Although web sites are responsible for + relaying of signaling between user agents, they are typically not + involved in media transport, encoding or decoding. For 1-1 calls, + user agents negotiate media to be sent and received. +

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+ In a conferencing scenario, a user agent can send media for + reception by dozens or even hundreds of receivers. To improve + scalability, applications make use of external servers, such as + selective forwarding units or conferencing bridges. These servers + negotiate media parameters with participants, ensuring consistency + across senders and receivers. This is more scalable than negotiation + between user agents, which would require N (N -1) negotiations. + Since typically senders encode with a single codec, and conferencing + servers do not support transcoding, a user agent cannot simply + "pick the one they like best". +

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Decoding/Encoding and Fingerprinting