In video coding, temporal scalability is the option to decode only some of the frames in a video stream instead of the whole stream. This enables an SFU for example to reduce the bitrate sent towards viewers who doesn’t have enough bitrate or CPU to handle the whole stream. It also assists devices that miss a packet to continue decoding the stream partially until an intra-frame is received.
Temporal scalability is one of the scalability aspects usually attributed to SVC. It is available for WebRTC in VP8 without the implementation of SVC.