DC-SESS-04

DC derived enforced

Backpressure discipline: every per-peer + per-mini-protocol channel is bounded; queue overflow is fail-fast TransportError::BackpressureExceeded rather than silent drop. No mpsc::unbounded_channel in any wire-session / mux-pump / dialer / keep-alive-session file.

Source: docs/planning/phase4-n-l-wire-protocol-invariants.md §1 (I-6)

Enforcement trace

Code

crates/ade_network/src/mux/transport.rs
crates/ade_runtime/src/network/mux_pump.rs
crates/ade_runtime/src/network/n2n_dialer.rs

Tests 2

crates/ade_network/src/mux/transport.rs::tests::mux_transport_duplex_inbound_overflow_returns_backpressure
crates/ade_network/src/mux/transport.rs::tests::mux_transport_duplex_round_trips_bytes_over_loopback

CI 1

ci_check_session_no_unbounded.sh

Cross-references

Strengthened in

Evidence notes

PHASE4-N-L S5+S6+S7+S8 (2026-05-26): MuxTransportDuplex uses bounded mpsc channels with try_send → TransportError::BackpressureExceeded on overflow. CI grep enforces no unbounded_channel constructor across the wire-session file set.