MPC-based ABR borrows from control theory: at each decision point, predict throughput for the next K segments, enumerate the K-segment rendition trajectories, score each by a utility function (bitrate − rebuffer penalty − switch penalty), pick the trajectory whose first rendition wins. K is usually 5–10 segments. The MPC paper (ACM SIGCOMM 2015) demonstrated that this lookahead approach outperformed both pure throughput-based and pure buffer-based ABRs on a wide range of network traces.
MPC's strength is that it can model both short-term throughput predictions and the cost of switching. It's also flexible — the utility function is configurable, so an operator can tune for "few switches at any cost" or "maximum average bitrate" or anything in between. The trade-off is computational cost: at each segment boundary, the player enumerates K-length trajectories across the rendition ladder. For 6 renditions and K=5 that's 7776 trajectories, which is computable but not free.
In production MPC ideas show up in Shaka Player's ABR (with a smaller lookahead than pure MPC), in Netflix's per-title ABR, and in Pensieve, which replaced MPC's predictive engine with a neural network. Pure academic MPC is less common in production; the practical pattern is "MPC structure with one-step lookahead and aggressive smoothing" rather than the full 10-segment search.
The book · Volume 3 of 7
Video Streaming: A Complete Guide to Video Delivery: From ABR and CDNs to Players, WebRTC, DRM, and the Economics of Streaming
MPC ABR picks renditions by planning several segments ahead, so its quality depends on how good the throughput forecast is and how the utility function weighs rebuffering. This volume covers MPC and the other ABR families in detail, including buffer-based and throughput-based rung selection, bitrate ladders, stall recovery and QoE measurement. Written by Nikolay Sapunov, CEO at Fora Soft.
Tuning MPC or another ABR algorithm to cut rebuffering without dropping quality?
Share your player logs or QoE data and we will deliver an ABR tuning plan with forecast settings, switch penalties and an A/B test design to prove the gain. 250+ video products shipped since 2005.
