The Rust BiFEP reference implementation (≈20.4k lines: 2,195 datastream, 989 datagram, 813 shared, 16,375 harness) achieves 28.2 MiB/s goodput at 37.0 µs per epoch operation for datastreams, and 420 MiB/s at 1.36 µs per atomic send/receive for datagrams; all 62,119 conformance assertions passed across 491 trials and 5,321 logical epochs, with 0 forged semantics across 360 datastream and 120 datagram active-integrity trials.
From 2026-chen-closing-loop-bidirectional — Closing the Loop: Bidirectional Fully Encrypted Protocols
· §VII; §VIII-A,B,C; Table II; Table V
· 2026
· arXiv preprint
Implications
BiFEP's per-epoch overhead (~37 µs for datastream at 1,200-byte schedule) is practical for integration into VPN or proxy tunnels; the datagram path (1.36 µs) is suitable for QUIC-based transports without significant latency penalty.
Cover expansion increases sharply as application load drops toward idle — protocol designers should budget for worst-case cover cost at low throughput and expose a configurable schedule generator so deployments can tune the expansion-versus-fingerprint tradeoff.