diff --git a/docs/ISSUES.md b/docs/ISSUES.md index a36232c6..22aa74d7 100644 --- a/docs/ISSUES.md +++ b/docs/ISSUES.md @@ -121,7 +121,14 @@ and the indicator shows non-zero loss under `tools/run-connected-loss-gate.ps1`. ## #260 — Portal-network wedge: outbound actions die + native/GPU memory climbs -**Status:** ROOT-CAUSED 2026-07-29 — **fix in flight as Campaign N** +**Status:** FIX IMPLEMENTED 2026-07-29 — **Campaign N slices N0–N6 all +shipped and reviewed** (outbound resend `43e60a69`, inbound +sequence-aligned ISAAC `46d209d0`, retail ack cadence `0265cc42`, NAK +emission + reclaim `852a59e3`, the permanent loss gate `4e290f00`, +handshake/assembler hardening `f9c5e47e`). The loss gate observes real +injected loss recovering in both directions with the cipher ledger +converged. CLOSES when the user's Coldeve endurance session passes the +historic 15-minute wedge horizon. Original root-cause record below. ([`docs/plans/2026-07-29-network-transport-campaign.md`](plans/2026-07-29-network-transport-campaign.md)). The wedge is missing packet-loss recovery in BOTH directions: (a) no outbound retransmission — ACE's `RequestRetransmit` lists are parsed and consumed diff --git a/docs/plans/2026-07-29-network-transport-campaign.md b/docs/plans/2026-07-29-network-transport-campaign.md index c76c9e74..8c58d632 100644 --- a/docs/plans/2026-07-29-network-transport-campaign.md +++ b/docs/plans/2026-07-29-network-transport-campaign.md @@ -1,6 +1,9 @@ -# Campaign N — Retail-Faithful Network Transport +# Campaign N — Retail-Faithful Network Transport -**Status: ACTIVE (approved 2026-07-29). Slices N0–N6.** +**Status: IMPLEMENTATION COMPLETE 2026-07-29 — all seven slices (N0–N6) +shipped and reviewed. Remaining acceptance: the user Coldeve endurance +session (§8 rung 4) — play past the historic 15-minute wedge horizon with +portal churn; the `[net-tick]`/`[net-final]` counters are the evidence.** acdream cannot survive a single lost UDP packet in either direction. This campaign ports retail's reliable-transport mechanism (the Sept 2013 named @@ -15,8 +18,8 @@ Read this before touching `src/AcDream.Core.Net/`. 1. **Outbound (the #260 wedge):** no sent-packet cache, no resend. ACE NAKs a client-sequence gap with `RequestRetransmit`; we parse the list and consume - it nowhere. One lost C2S datagram → ACE buffers everything after the gap - forever → all actions void, position updates void → ACE stops streaming new + it nowhere. One lost C2S datagram → ACE buffers everything after the gap + forever → all actions void, position updates void → ACE stops streaming new areas (the #256 "invisible portals") while the session stays alive on cleartext acks. Reproduced twice on Coldeve 2026-07-29 with the `ACDREAM_PROBE_NET` probe (`artifacts/coldeve-probe-20260729/`, local). @@ -25,7 +28,7 @@ Read this before touching `src/AcDream.Core.Net/`. shifts the keystream permanently; every later encrypted packet fails checksum and burns another word. Inbound silent forever. -Loopback ACE never drops packets — every historical gate was structurally +Loopback ACE never drops packets — every historical gate was structurally blind to both bugs. Slice N5's loss gate removes that blindness permanently. ## 2. The retail mechanism (port target) @@ -39,89 +42,89 @@ outbound = `RecipientData` + `ClientFlowQueue` + `SentPacketStore` (under ### 2.1 Outbound resend - Every reliable packet (fragments aboard) is cached AFTER a successful send - (`FlowQueue::TransmitNewPackets @ 0x00547A60` → `SentPacketStore:: + (`FlowQueue::TransmitNewPackets @ 0x00547A60` → `SentPacketStore:: AddSentPacket @ 0x0054AB00`), with disposable optional headers stripped first (`NetPacket::RemoveDisposableOptionalHeaders @ 0x00549510`). Under - our standalone-control design (§4) reliable packets never carry optional - headers, so the strip is a provable no-op — assert `optionalLength == 0` + our standalone-control design (§4) reliable packets never carry optional + headers, so the strip is a provable no-op — assert `optionalLength == 0` in `SentPacketStore.Add`. -- Server `RequestRetransmit` (0x1000) → merge-insert ids wrap-safe sorted +- Server `RequestRetransmit` (0x1000) → merge-insert ids wrap-safe sorted (`FlowQueue::EnqueueAcks @ 0x005488E0`); `ids[0]` doubles as an implicit cumulative ack (`RecipientData::ProcessNaks @ 0x00547010`). Ids no longer - cached → retail answers `RejectRetransmit`; we drop silently (row TS-57). + cached → retail answers `RejectRetransmit`; we drop silently (row TS-57). - Resend (`FlowQueue::TransmitAcks @ 0x005485B0` / `DequeueAck @ - 0x005472F0`): re-emit with a REBUILT 20-byte header — flags + 0x005472F0`): re-emit with a REBUILT 20-byte header — flags `Retransmission|EncryptedChecksum` (=3; |`BlobFragments` =7 with fragments), `Time` = the CURRENT interval id, `Sequence`/`DataSize` verbatim, checksum = fresh header hash + stored sealed checksum. Body bytes untouched; **the original ISAAC key is reused** (`CryptoSystem:: - EncryptData @ 0x0065FF40` takes the key as an optional in/out — null draws, + EncryptData @ 0x0065FF40` takes the key as an optional in/out — null draws, non-null reuses). Never a new keystream word. -- `AckSequence` (0x4000) inbound → wrap-safe max watermark → prune strictly +- `AckSequence` (0x4000) inbound → wrap-safe max watermark → prune strictly older (`SentPacketStore::Flush @ 0x0054ACD0`, pops from FIFO head while - `seqNum < watermark`). No timer-based resend exists — resend only on + `seqNum < watermark`). No timer-based resend exists — resend only on explicit NAK. -- Sequence allocation: `highestIDSent_` starts 1; `++`; wrap 0xFFFFFFFF → 1 +- Sequence allocation: `highestIDSent_` starts 1; `++`; wrap 0xFFFFFFFF → 1 (never 0). Unsequenced packets reuse the current watermark, cleartext, no ISAAC word. -- Pump order per frame (`FlowQueue::Empty @ 0x00548A20`): NAKs → retransmits - → new packets. +- Pump order per frame (`FlowQueue::Empty @ 0x00548A20`): NAKs → retransmits + → new packets. ### 2.2 Inbound sequencing + ISAAC discipline -**No transport reorder buffer** — packets process on arrival -(`SharedNet::ProcessPacket @ 0x00544790` → `ProcessNewSeqNum @ 0x00544690`): +**No transport reorder buffer** — packets process on arrival +(`SharedNet::ProcessPacket @ 0x00544790` → `ProcessNewSeqNum @ 0x00544690`): 1. `SeqIDSanityCheck @ 0x00543A20`: drop if seq is newer than `highestIDReceived_ + 0x7FFF` (wrap-safe). 2. Encrypted + not newer than the watermark = duplicate/late arrival: remove - from the NAK set — hit → decrypt with the **parked pre-drawn key**; - miss → drop silently at zero keystream cost. -3. Newer than the watermark → gap walk (`ProcessNewestSeqNum @ 0x00541930`): - for each missing id (skip 0) `AddNakked(id, null)` — **pre-draws one + from the NAK set — hit → decrypt with the **parked pre-drawn key**; + miss → drop silently at zero keystream cost. +3. Newer than the watermark → gap walk (`ProcessNewestSeqNum @ 0x00541930`): + for each missing id (skip 0) `AddNakked(id, null)` — **pre-draws one inbound ISAAC word per missing id, in sequence order, BEFORE the arriving packet's own key**, parking it beside the id (`ReceiverData::AddNakked @ 0x00549240`, idempotent). Cleartext packets walk to `seq+1` (they borrow an already-delivered sequence). Then watermark = seq. 4. Encrypted packets then decrypt with the parked key or the next drawn word. -5. Parse failure on a sequenced packet → re-park its consumed key +5. Parse failure on a sequenced packet → re-park its consumed key (`AddNakked(seq, &key)`), so the retransmission decodes. -6. Inbound `RejectRetransmit` (`SharedNet::HandleEmptyAck @ 0x005448F0`) → +6. Inbound `RejectRetransmit` (`SharedNet::HandleEmptyAck @ 0x005448F0`) → remove ids from the NAK set, silent abandonment. This keeps the inbound keystream aligned to SEQUENCE order, not arrival order -— the invariant the whole inbound port hangs on. +— the invariant the whole inbound port hangs on. ### 2.3 Ack/NAK sweep Per-frame per-connection sweep (`ClientNet::ProcessConnection @ 0x00545450`), mutually exclusive on ONE shared timestamp (`ReceiverData::timeStamp_`): -- NAK set non-empty → `RequestRetransmit`: ≤114 ids ascending, cleartext, +- NAK set non-empty → `RequestRetransmit`: ≤114 ids ascending, cleartext, 0.6 s gate (`SharedNet::EnqueueNaks @ 0x00543BD0`, `ReceiverData::GetNaks @ 0x005490C0`), and NO ack this sweep. -- Else → one cumulative `AckSequence` carrying `highestIDReceived_`, +- Else → one cumulative `AckSequence` carrying `highestIDReceived_`, unsequenced + cleartext, 2.0 s gate (`SharedNet::EnqueuePak @ 0x00543B10` - — the ONLY 0x4000 construction site in the binary; retail never acks + — the ONLY 0x4000 construction site in the binary; retail never acks per-packet). -### 2.4 Keepalive/time/flow (mostly deferred — §5) +### 2.4 Keepalive/time/flow (mostly deferred — §5) TimeSync (8-byte double) + EchoRequest (4-byte float) every ~3 s (`ClientFlowQueue::IncrementLocalInterval @ 0x00547F10`); inbound TimeSync adopts the server clock; Flow report sent on remote-interval advance; -inbound Flow ignored, no throttle (`WireRoomLeft` is a folded `return 1` — +inbound Flow ignored, no throttle (`WireRoomLeft` is a folded `return 1` — verified); dead link at 140 s without inbound data (self-stall guarded) with referral auto-reconnect; 0.5 s interval clock feeds `ProtoHeader::interval_` (our `PacketHeader.Time`). ### 2.5 Constants -464 max payload after the 20-byte header · 448 fragment payload · 114 NAK -list cap · +0x7FFF sanity window · 0.5 s interval tick · 2.0 s ack gate · -0.6 s NAK gate · ~3 s TimeSync/Echo · 140 s dead link · 10 s disconnect -drain · `0xBADD70DD` checksum placeholder · sequence init 1, wrap -0xFFFFFFFF→1 · 0.333 s ConnectResponse handshake resend. +464 max payload after the 20-byte header · 448 fragment payload · 114 NAK +list cap · +0x7FFF sanity window · 0.5 s interval tick · 2.0 s ack gate · +0.6 s NAK gate · ~3 s TimeSync/Echo · 140 s dead link · 10 s disconnect +drain · `0xBADD70DD` checksum placeholder · sequence init 1, wrap +0xFFFFFFFF→1 · 0.333 s ConnectResponse handshake resend. ## 3. ACE constraints (Coldeve runs ACE; references in the MAIN repo checkout) @@ -129,37 +132,37 @@ drain · `0xBADD70DD` checksum placeholder · sequence init 1, wrap |---|---|---| | NAKs client gaps at `expected+2`, 1 s limit, arrival-driven ONLY | NetworkSession.cs:351-363 | after one C2S loss two more sends must arrive before ACE NAKs; a quiet client is never NAKed | | Crypto search window 256 keys; re-key orphans permanently | CryptoSystem.cs:30-49 | NEVER re-key a resend; NEVER resend an already-accepted packet | -| Watermark advances on ANY packet with flags ≠ exactly `AckSequence` | NetworkSession.cs:474-476 | standalone unsequenced control packets other than exact-`AckSequence`/exact-`RequestRetransmit` can skip a REAL packet forever (the self-induced wedge) | +| Watermark advances on ANY packet with flags ≠ exactly `AckSequence` | NetworkSession.cs:474-476 | standalone unsequenced control packets other than exact-`AckSequence`/exact-`RequestRetransmit` can skip a REAL packet forever (the self-induced wedge) | | Honours only CLEARTEXT NAKs; encrypted NAKs silently ignored | NetworkSession.cs:283-284 | no NAK piggybacking; NAKs never refresh ACE's 60 s timeout | | Ack-only dedup exemption requires flags == `AckSequence` exactly | NetworkSession.cs:342-343 | equality check, not HasFlag | | ACE never proactively resends S2C; S2C cache prunes at 120 s | NetworkSession.cs:675-708, :251-262 | the client MUST NAK or inbound stalls; old NAKs get RejectRetransmit | | C2S fragment sequence strictly contiguous or dispatch stalls silently | NetworkSession.cs:532-543 | packet-level retransmission heals it automatically | | ACE sends TimeSync/20 s, cumulative ack/2 s, EchoResponse on request; NO disconnect/error packets ever | NetworkSession.cs:207-216, grep | every transport death is silence | | Rejects AckSequence/TimeSync/EchoRequest/Flow during AuthLoginRequest | Session.cs:101-102 | no sweep before negotiation completes | -| Inbound `Header.Time` ignored | grep | our interval field is cosmetic against ACE — safe | +| Inbound `Header.Time` ignored | grep | our interval field is cosmetic against ACE — safe | ## 4. Design -`src/AcDream.Core.Net/Transport/` — retail's split adapted to one login + one +`src/AcDream.Core.Net/Transport/` — retail's split adapted to one login + one world connection on one frame thread. `TransportClock` (injectable monotonic source + 0.5 s interval counter), `SequenceMath` (`IsNewer(a,b) => unchecked((int)(a-b)) > 0`), `SentPacketStore` (FIFO of rented wire buffers), `OutboundFlowQueue` (outbound ISAAC, HighestIdSent, fragment seq, pending resends, NAK/ack consumption), `InboundSequenceTracker` (inbound ISAAC, -HighestIdReceived, NAK set `SortedDictionary` seq→parked key), +HighestIdReceived, NAK set `SortedDictionary` seq→parked key), `AckNakScheduler` (ONE shared timestamp; per sweep NAK xor ack), `ReliableTransport` (composition + `Sweep()`), `TransportStats` (unconditional counters; printing probe-gated). Cache entry: `{ Sequence, rented Buffer (header+body), BodyLength, -SealedChecksum (= payloadHash ^ isaacKey — retail `NetPacket::checksum_`), -IsaacKey, HasFragments }`. Resend rewrites ONLY the header per §2.1; +SealedChecksum (= payloadHash ^ isaacKey — retail `NetPacket::checksum_`), +IsaacKey, HasFragments }`. Resend rewrites ONLY the header per §2.1; `PacketCodec.FinalizeInPlace` gains an overload returning `(isaacKeyUsed, sealedChecksum)`; the old signature forwards. -Inbound: codec splits pure-parse (`TryParseBorrowed` — no keystream) from +Inbound: codec splits pure-parse (`TryParseBorrowed` — no keystream) from `VerifyChecksum(header, headerHash, payloadHash, uint? isaacKey)`; the -tracker owns every key decision (retail's own factoring — `EncryptData`'s +tracker owns every key decision (retail's own factoring — `EncryptData`'s optional key parameter). `TryDecodeBorrowed(datagram, IsaacRandom?)` is deleted; owned `TryDecode` stays (test-only). @@ -173,21 +176,21 @@ unbounded like retail (ACE acks every 2 s; steady state is tens of entries); ## 5. Scope deferrals (divergence-register rows, filed in-slice) -- **TS-57** no outbound RejectRetransmit — ACE no-ops it; the standalone - unsequenced form trips the watermark hole (§3 row 3). -- **AP-125** standalone control packets only, no `CoalesceData` piggyback — +- **TS-57** no outbound RejectRetransmit — ACE no-ops it; the standalone + unsequenced form trips the watermark hole (§3 row 3). +- **AP-125** standalone control packets only, no `CoalesceData` piggyback — piggybacked NAKs become encrypted, which ACE ignores. -- **TS-58** no TimeSync/EchoRequest keepalive — standalone-unsafe against +- **TS-58** no TimeSync/EchoRequest keepalive — standalone-unsafe against the watermark hole; our 2 s ack already refreshes ACE's 60 s timeout. -- **TS-59** no Flow report — ACE parses and has no handler. -- **AD-49** blob-layer ephemeral ordering stamps not ported — provably a +- **TS-59** no Flow report — ACE parses and has no handler. +- **AD-49** blob-layer ephemeral ordering stamps not ported — provably a no-op against ACE (fragment `Id` is constant 0x80000000 and the stamp table keys on ACE's per-message-unique fragment sequence, so `FragIsObsoleteEmphemeral @ 0x0054A450` can never fire). -- **TS-60** no 140 s dead-link/referral auto-reconnect — LinkStatus exposes +- **TS-60** no 140 s dead-link/referral auto-reconnect — LinkStatus exposes the input; reconnect is Runtime's, its own campaign. - **TS-61** UDP send-failure burns the sequence+key (retail retries from the - queue head) — effectively unreachable. + queue head) — effectively unreachable. - **AP-126** one monotonic clock for all gates (retail's cur/local split immaterial to the gates we port). - Multi-fragment outbound (>448 B) stays unimplemented (nothing sends >448; @@ -205,7 +208,7 @@ unbounded like retail (ACE acks every 2 s; steady state is tens of entries); | N5 | Observability + LossyTransportDecorator + connected loss gate | M | partly | Opus | unit + loss gate | | N6 | Optional: ConnectResponse 0.333 s retransmit; assembler TTL | S | yes | Opus | unit + local ACE | -N1–N5 all touch `WorldSession.cs`: strictly sequential, ONE agent at a time. +N1–N5 all touch `WorldSession.cs`: strictly sequential, ONE agent at a time. Implementers Sonnet; a redo escalates to Opus; every diff reviewed by the Review-column model before commit. Key per-slice test specs are in the approved plan (`~/.claude/plans/mac-os-is-not-robust-sphinx.md`) and travel @@ -213,22 +216,22 @@ verbatim in each implementer prompt. ## 7. Landmines (verbatim in every implementer prompt) -1. Resends are NOT byte-identical — flags gain `Retransmission`, `Time` +1. Resends are NOT byte-identical — flags gain `Retransmission`, `Time` advances, the header hash MUST be recomputed; checksum = new header hash + stored sealed checksum. A verbatim resend fails ACE's CRC silently. -2. Never draw a new ISAAC word on a resend — one re-key permanently orphans +2. Never draw a new ISAAC word on a resend — one re-key permanently orphans a key in ACE's 256-entry window. -3. Never resend unrequested — a duplicate of an accepted packet burns up to +3. Never resend unrequested — a duplicate of an accepted packet burns up to the whole window. 4. The inbound gap-walk draws parked keys BEFORE the arriving packet's own - key, in sequence order — reversed, the stream is off by the gap size + key, in sequence order — reversed, the stream is off by the gap size forever. 5. Ack flags are an EQUALITY check (`Flags == AckSequence`), never HasFlag. 6. NAKs are cleartext (`Flags == RequestRetransmit` exactly) or ACE ignores them; NAKs do not refresh ACE's timeout. -7. The 0.6 s NAK gate and 2.0 s ack gate share ONE timestamp — a NAK delays +7. The 0.6 s NAK gate and 2.0 s ack gate share ONE timestamp — a NAK delays the next ack and vice versa; never both in one sweep. -8. The sweep must also run inside the blocking handshake pump loops — the +8. The sweep must also run inside the blocking handshake pump loops — the EnterWorld CreateObject flood precedes the first `Tick()`. 9. ACE/holtburger reference sources live in the MAIN repo checkout (`C:\Users\erikn\source\repos\acdream\references\`), not in worktrees. @@ -238,10 +241,10 @@ verbatim in each implementer prompt. 1. Per slice: `dotnet build` + full `dotnet test -c Release` + slice gate + one commit (retail symbol+address citations) + model review + revert SHA recorded here. -2. N1–N5: `tools/run-connected-world-lifecycle-gate.ps1` vs local ACE; +2. N1–N5: `tools/run-connected-world-lifecycle-gate.ps1` vs local ACE; N2/N3 add the canonical nine-stop route. 3. From N4: `tools/run-connected-loss-gate.ps1` at `ACDREAM_NET_DROP_PCT=2` - vs local ACE — passes only with NON-ZERO resend/NAK counters. + vs local ACE — passes only with NON-ZERO resend/NAK counters. 4. Final: one user Coldeve session past the 15-minute wedge horizon with portal churn, after N5. `[net-tick] nak-in/s` becomes the first direct measure of real C2S loss the project has had. @@ -251,10 +254,10 @@ verbatim in each implementer prompt. | Slice | Status | Commit | Notes | |---|---|---|---| -| N0 | complete | `7e9134b4` + `e3958610` | ACE-behaviour double + virtual clock + lossy link; the review fix-up added the `Session.CheckState` inbound gate, faithful `SendBundle` coalescing/splitting, two-phase termination, an ACE-loose C2S fragment parse, and ACE's MessageBuffer edge cases. 687 Core.Net tests green. N1 folded in the re-review's `ProcessFragment` two-branch split (existing-buffer checks Complete; new-buffer parks without checking — the zero-count buffer stays parked). | -| N1 | complete | `43e60a69` | Outbound sent-packet cache + resend on NAK (`Transport/`: `TransportClock`, `SequenceMath`, `SentPacketStore`, `OutboundFlowQueue`, `ReliableTransport`, `TransportStats`); `PacketCodec.FinalizeInPlace` sealed-checksum overload; `WorldSession` sweep in Tick + both handshake pump loops; TS-57 filed, TS-27 narrowed to inbound-only. **Fable review PASS.** Advisories: fresh sends keep `Time=0` (byte-identical wire; retail stamps the interval on every packet and ACE ignores the field — N3 folds the retail stamp in with the cadence work); the stale-NAK single-redundant-resend window is shared with retail (pending prunes at flush, after transmit — same frame order as `RecipientData::UseTime`). | -| N2 | complete | `46d209d0` — **Fable review PASS** (tracker/codec-split/admission verified pre-commit against retail rules; gates lifecycle+nine-stop both PASS) | Inbound sequence-aligned ISAAC + NAK set (`Transport/InboundSequenceTracker`: watermark, sanity window, duplicate/parked-key path, sequence-ordered gap-walk pre-draw, verify-failure re-park, RejectRetransmit abandonment — `ProcessNewSeqNum @ 0x00544690`, `ProcessNewestSeqNum @ 0x00541930`, `SeqIDSanityCheck @ 0x00543A20`, `AddNakked @ 0x00549240`, `HandleEmptyAck @ 0x005448F0`); `PacketCodec` split into keystream-free `TryParseBorrowed` + `VerifyChecksum` (`TryDecodeBorrowed` deleted); `RejectRetransmit` ids exposed on both optional-header decoders; `ReliableTransport` now owns both keystreams; stats gained `InboundDupsDropped`/`InboundSanityDrops`/`ChecksumFailures`/`KeysParked`. Watermark init 1 is the AD-50 ACE adaptation (retail zero-init vs ACE's re-prime dance — first encrypted S2C is sequence 2; holtburger api.rs:30 agrees); pinned by the clean-lifecycle conformance test (zero NAKs, min encrypted S2C sequence == 2). 716 Core.Net tests green. **N3/N4 handoff note:** the interim per-packet reflex ack acks the ARRIVING sequence even while a gap is parked, so ACE prunes the lost id from its S2C cache (`AcknowledgeSequence` strictly-below) before N4 can NAK it — message-level recovery of a real loss needs N3's retail NAK-xor-ack sweep (§2.3's mutual exclusivity is load-bearing). Also noted for N4: ACE's `RejectRetransmit` consumes a fresh CLEARTEXT sequence via FlushPackets (no keystream word), so the client's gap walk parks a word for an id that never had one server-side — a real retail-vs-ACE incompatibility to resolve in N4's design (retail never assigns new sequences to cleartext). | -| N3 | complete | `0265cc42` — Opus review PASS (advisories folded into N4: transitional-state wording, SharedInit citation, pump-order wording, control-packet Time/Iteration rule, stale budget-break comment) | AckNakScheduler + 2.0 s cumulative ack (`Transport/AckNakScheduler`): ONE shared timestamp (`ReceiverData::timeStamp_` @ +0x10) arbitrating NAK-xor-ack per sweep (`ClientNet::ProcessConnection @ 0x00545450`); the ack is one cleartext exact-flags `AckSequence` carrying the tracker's `highestIDReceived_` behind the >= 2.0 s gate (`SharedNet::EnqueuePak @ 0x00543B10` — the binary's only 0x4000 construction site), armed at connection birth (`ReceiverData::Init @ 0x00548EF0`). The Phase 4.9 per-packet reflex ack and `WorldSession.SendAck` are DELETED; the `[net-tick]` acks/s probe now reads `Stats.AcksSent`. Sweep order per `FlowQueue::Empty @ 0x00548A20`: interval clock, NAK/ack arbitration, pending resends, prune. **N3 transitional state (closed by N4):** a non-empty NAK set suppressed the ack and emitted NOTHING — the exposure was real even on loopback, just low-probability: one receive-buffer drop parks an id, every later sweep takes the silent NAK branch, acks stop (witness: `[net-tick] acks/s=0`), and ACE disconnects the quiet session at its 60 s timeout. N4 completed the branch. **N1 advisory retired (fold-in):** fresh reliable sends now stamp `Header.Time` = the current interval id (`FlowQueue::TransmitNewPackets @ 0x00547A60`, header build at 0x00547A84); ACE ignores inbound `Header.Time`, so the wire is unaffected. New `WorldSession.TransportClockSource` seam drives the gate on virtual time. 723 Core.Net tests green (keepalive property proven: a quiet session's 2 s acks refresh ACE's 60 s deadline across a 120 s virtual horizon; storm collapse: a 50-packet flood → ONE ack; the model accepts the reused-sequence ack without advancing its watermark). Connected lifecycle + canonical nine-stop gates PASS. | -| N4 | complete | `852a59e3` — **Opus review PASS** (reclaim invariant attacked from five angles, held; NAK fidelity verified to the x87 masks; AP-125 filed + F1 false-arithmetic wording + F5 ordinal sentinel fixed in the acceptance commit; F3 Iteration-on-fresh-sends folds into N5) | Client NAK emission + RejectRetransmit consumption. `AckNakScheduler` completes the NAK branch: one cleartext exact-flags `RequestRetransmit` per sweep behind the STRICT 0.6 s gate on the ONE shared timestamp (`SharedNet::EnqueueNaks @ 0x00543BD0` — the 0x41-mask x87 test at 0x00543C03 proceeds only on strictly-greater, contrast the ack's >=), body u32 count + ids ascending capped at 114 (`ReceiverData::GetNaks @ 0x005490C0`, cap 0x72), borrowed sequence, never an ack in a NAK sweep. Control-header rule decided for BOTH emissions: `Time` = interval id, `Iteration` = session iteration, per the shared retail header build (`FlowQueue::TransmitNewPackets @ 0x00547A60` @ 0x00547A84); ACE reads neither. THE design piece: the AD-51 reclaimed-word pool in `InboundSequenceTracker` closes the ACE cleartext-reject keystream hazard the N2 ledger row recorded — ACE's `RejectRetransmit` consumes a fresh cleartext sequence with NO keystream word, so the gap walk mis-parks a word for it and the whole inbound stream runs one word ahead. On a VALIDATED cleartext reject (`WorldSession` calls `OnCleartextRejectSequence` post-checksum), the tracker removes the mis-park, bubble-shifts every later-drawn parked word down one position (per-word draw ordinals; ascending id ⇔ ascending draw order), and pools the excess for the next fresh draws, consumed lowest-draw-order-first — exact for any number of interleaved rejects in any arrival order (a plain FIFO is NOT: reject-after-higher-arrival crosses the parked chain, and dual out-of-order rejects pool out of draw order — both pinned by tests). Reject BODY ids keep N2's discard (word-bearing server-side, consumed-in-place). N3 advisories all folded: honest transitional wording (above), `ReceiverData::SharedInit @ 0x00548EF0` (from `Init @ 0x00548FA0`) citation, `FlowQueue::Empty` pump-order comment (TransmitNaks → TransmitAcks → TransmitNewPackets, interval increment LAST @ 0x00548A9D; our clock-first order is cosmetic vs ACE), the Time/Iteration rule, and the stale `WorldSession` budget-break comment. Gate arithmetic hardened: gate ticks now round (0.6 has no exact double; truncation opened the strict gate AT the boundary). 737 Core.Net tests green, including: strict-gate boundary, shared-timestamp both directions, NAK-suppresses-ack, full wire-shape + 114-cap pins, model-served retransmission round trip, five tracker reclaim proofs, the 130-s virtual prune → fresh-sequence reject system test (victim abandoned, later traffic decodes, pool drains to zero), 10 s long-loss (NAKs on the gate cadence, zero acks, heal inside the window), and the capstone soak: 2% seeded bidirectional loss × 10,000 messages → zero message loss both ways, ACE crypto headroom 256 at convergence with a ≥250 no-erosion floor mid-flight, NAK set / reclaim pool / pending resends / ACE out-of-order buffer all zero, cache at the single watermark entry (retail Flush prunes STRICTLY below the ack). Soak notes: ACE never NAKs a quiet client (§3 row 1), so convergence keeps a C2S trickle flowing — a real idle-client tail loss heals only on the next action, an ACE constraint outside N4's scope. | -| N5 | complete | `4e290f00` — **Opus review PASS** (structural absence + arming gate + un-gameability + teardown all verified; ledger arithmetic reconciled). Acceptance folded in the review's gate strengthenings: per-direction recovery conjunction + the three keystream-health invariants (cksum-fail/sanity-drop/uncached-nak == 0) + the EnterWorldBody unrecoverable-tail caveat. Revert: `git revert 4e290f00d86ebd320d2da609fd7cd15d7175c4f0`. Test-collection hygiene (static NetDiagnostics mutation) folds into N6 | Loss observability + the LossyTransportDecorator + the connected loss gate — the permanent removal of the loopback blindness (§1). `[net-tick]` gains `resend/s nak-out/s nak-in/s rej-in/s dup-drop/s parked/s reclaim/s cache= nakset=` (window deltas mirroring acks/s; `TransportStats` gains `RejectsReceived`; string work probe-gated, counters unconditional) and `WorldSession.Dispose` emits one cumulative `[net-final]` totals line so the gate asserts exact counters, not rounded rates. N4-review F3 folded: fresh reliable sends stamp `Iteration` = the session iteration through the same shared retail header build already cited for `Time` and the N4 control packets (`FlowQueue::TransmitNewPackets @ 0x00547A60`, the build at 0x00547A84/0x00547AA8) — the control-header rule now holds across all three send shapes; ACE reads neither field inbound. `Transport/LossyTransportDecorator`: deterministic seeded per-direction loss (`ACDREAM_NET_DROP_PCT`/`_SEED`/`_DIR` via `NetDiagnostics` typed properties, Rule 5), armed only after the first ENCRYPTED outbound datagram is forwarded (parse-free flags-word check — the cleartext handshake always survives; handshake loss belongs to N6), structurally absent at 0% (`WrapIfConfigured` returns the raw transport; the default factory is the only production seam). The logoff-confirmation wait now runs the transport sweep — retail's pump (`Client::UseTime @ 0x00411C40`) never stops before `LogOffServer`, and the loss gate exposed that a dropped S2C confirmation was gap-detected but never NAKed during `Dispose`. `tools/run-connected-loss-gate.ps1` (default 2%/seed 1) runs the standard lifecycle route through the decorator vs local ACE and FAILS unless `[net-final]` shows resends>0 OR nak-out>0 OR nak-in>0 AND the decorator's own dropped ledger is non-zero — a loss gate that never dropped proves nothing, asserted explicitly. The lifecycle gate defensively clears the drop vars (decorator-absent baseline). **First loss-observing gate evidence (2026-07-29, 2%/seed 1, local ACE):** decorator dropped out=3 in=10 of forwarded out=183 in=496; `[net-final] resends=2 nak-in=2 nak-out=6 rej-in=0 acks-out=114 acks-in=119 dup-drop=0 sanity-drop=0 cksum-fail=0 parked=9 reclaimed=0 uncached-nak=0 cache=1 nakset=0` — both recovery directions fired on a real connected route (ACE NAK → cached resend; client gap-walk park → NAK → ACE retransmit), all six checkpoints validated, graceful logout confirmed, ACE recorded the transport Disconnect, RESULT=PASS. The gate immediately paid for itself: it exposed that the Dispose logoff-confirmation wait processed inbound but never swept the transport, so a lost S2C confirmation could be gap-detected yet never NAKed — fixed by running the sweep in that third blocking pump (retail's `Client::UseTime @ 0x00411C40` pump runs until `LogOffServer`). Known tail caveat recorded in the gate header: a drop landing on the single-shot logoff request or transport Disconnect (~pct each) is unrecoverable by ACE's arrival-driven NAK design (§3 row 1) — rerun with another seed, never widen teardown tolerances. #261 filed for `LinkStatusSnapshot.PacketLossPercentage` (retail `CLinkStatusAverages` formula required; inventing a ratio forbidden). 747 Core.Net tests green (decorator determinism/direction/arming/structural-absence, the 5% seeded WorldSession lossy lifecycle with zero message loss + Headroom 256, `[net-tick]` field pins, Iteration-stamp pins). | -| N6 | complete | `f9c5e47e` — **Opus review PASS** (all six retail address claims verified incl. the three distinct gate strictness masks; packet-identity, latch, TTL, and ring all clean). Acceptance settles LOW-2 (TS-58/TS-59/TS-60/TS-61/AP-126 filed) + INFO-4 (DropAll resets the completed ring) + INFO-5 (the post-acceptance retry drop is NetworkManager's pre-route, not CheckState — same silent pre-CRC outcome). LOW-1 noted: retry cadence dilates to ~0.5 s via the pump's 250 ms receive granularity — mechanism/constant/strictness retail-exact, fewer retries than retail, harmless. Revert: `git revert f9c5e47e`. | ConnectResponse handshake retransmit + fragment-assembler eviction — the final implementation slice. **Retransmit:** while unconfirmed, the Connect character-list pump resends the IDENTICAL cleartext ConnectResponse (same sequence 1, same cookie, the one encoded datagram — no new outbound state) on retail's strict 0.333333333 s gate (`ClientNet::ProcessConnection @ 0x00545450` case `cs_ConnectionRequestAcked` at 0x0054547B, the constant at 0x00545481, the mask-0x41 strictly-greater test at 0x0054548C; `ClientNet::SendConnectAck @ 0x005440F0` re-stamps `lastSentHandshake_` at 0x00544102 and rebuilds the same cookie packet). Confirmation = the first checksum-valid post-negotiation packet without the ConnectRequest flag, retail's `cs_ConnectionRequestAcked → cs_Connected` edge (`ClientNet::ProcessPacket @ 0x00545100`: the 0x40000 exclusion at 0x0054514E, `SetConnectionState(..., 5)` at 0x00545160). The cadence rides the TransportClock (virtual-clock testable via `TransportClockSource`); the Connect deadline stays wall-clock. ACE-safety pinned against the N0 model: a duplicate while still `AuthConnectResponse` re-routes idempotently through NetworkManager's pre-route; after acceptance `CheckState` clause 2 drops it pre-CRC at zero keystream cost. Pre-N6 a lost ConnectResponse was a hang to the Connect deadline — routine on a real path, and the N5 decorator deliberately arms after this window, so nothing covered it. **Assembler eviction (AD-52):** partials evict 60 s after their last accepted fragment (re-stamp-on-update per retail `ArrivedEphInfo::UpdateNetBlobID @ 0x0054AE00`), swept from `ReliableTransport.Sweep` on retail's 5 s flush cadence (`Indicator::FlushTimedOutEphInfo @ 0x0054A3D0`, gate at 0x0054A3DC; per-entry `fTimedOut @ 0x0054AE30`) — N4's RejectRetransmit abandonment had made an unrecoverable partial a reachable permanent state. A 64-entry completed-sequence ring drops late duplicates of already-completed messages instead of re-partialing them (the completed-then-duplicate leak). 60 s is a floor, never a tunable to shrink. **Fold-ins:** N5-review LOW-5 — `NetProbeTests` + `LossyTransportDecoratorTests` (the static-`NetDiagnostics`/`Console.SetOut` mutators) share one `DisableParallelization` xunit collection so they never run alongside classes constructing `WorldSession`. 757 Core.Net tests green (drop-first-ConnectResponse-retry-heals with exactly one retry and none after confirmation; clean handshake sends exactly one; server-responses-lost retries drop harmlessly at the model while the N2/N4 gap-walk → NAK → cached-retransmit path heals the handshake responses; model-level duplicate-after-acceptance CheckState pin; assembler TTL floor boundary/refresh-on-update/ring-drop/ring-bound; transport-level sweep eviction). Connected lifecycle gate PASS (capped six-checkpoint route + uncapped reconnect, graceful exits, zero failures). The N5-STRENGTHENED loss gate PASS on its first live run (2%/seed 1, local ACE): decorator `[net-loss] dropped out=3 in=10 forwarded out=181 in=496 armed=True`; `[net-final] resends=1 nak-in=1 nak-out=5 rej-in=0 acks-out=114 acks-in=116 dup-drop=0 sanity-drop=0 cksum-fail=0 parked=8 reclaimed=0 uncached-nak=0 cache=1 nakset=0` — the per-direction recovery conjunction held (C2S: resends+nak-in > 0; S2C: nak-out > 0), all three keystream-health invariants zero, ledger converged at the single watermark cache entry. | +| N0 | complete | `7e9134b4` + `e3958610` | ACE-behaviour double + virtual clock + lossy link; the review fix-up added the `Session.CheckState` inbound gate, faithful `SendBundle` coalescing/splitting, two-phase termination, an ACE-loose C2S fragment parse, and ACE's MessageBuffer edge cases. 687 Core.Net tests green. N1 folded in the re-review's `ProcessFragment` two-branch split (existing-buffer checks Complete; new-buffer parks without checking — the zero-count buffer stays parked). | +| N1 | complete | `43e60a69` | Outbound sent-packet cache + resend on NAK (`Transport/`: `TransportClock`, `SequenceMath`, `SentPacketStore`, `OutboundFlowQueue`, `ReliableTransport`, `TransportStats`); `PacketCodec.FinalizeInPlace` sealed-checksum overload; `WorldSession` sweep in Tick + both handshake pump loops; TS-57 filed, TS-27 narrowed to inbound-only. **Fable review PASS.** Advisories: fresh sends keep `Time=0` (byte-identical wire; retail stamps the interval on every packet and ACE ignores the field — N3 folds the retail stamp in with the cadence work); the stale-NAK single-redundant-resend window is shared with retail (pending prunes at flush, after transmit — same frame order as `RecipientData::UseTime`). | +| N2 | complete | `46d209d0` � **Fable review PASS** (tracker/codec-split/admission verified pre-commit against retail rules; gates lifecycle+nine-stop both PASS) | Inbound sequence-aligned ISAAC + NAK set (`Transport/InboundSequenceTracker`: watermark, sanity window, duplicate/parked-key path, sequence-ordered gap-walk pre-draw, verify-failure re-park, RejectRetransmit abandonment — `ProcessNewSeqNum @ 0x00544690`, `ProcessNewestSeqNum @ 0x00541930`, `SeqIDSanityCheck @ 0x00543A20`, `AddNakked @ 0x00549240`, `HandleEmptyAck @ 0x005448F0`); `PacketCodec` split into keystream-free `TryParseBorrowed` + `VerifyChecksum` (`TryDecodeBorrowed` deleted); `RejectRetransmit` ids exposed on both optional-header decoders; `ReliableTransport` now owns both keystreams; stats gained `InboundDupsDropped`/`InboundSanityDrops`/`ChecksumFailures`/`KeysParked`. Watermark init 1 is the AD-50 ACE adaptation (retail zero-init vs ACE's re-prime dance — first encrypted S2C is sequence 2; holtburger api.rs:30 agrees); pinned by the clean-lifecycle conformance test (zero NAKs, min encrypted S2C sequence == 2). 716 Core.Net tests green. **N3/N4 handoff note:** the interim per-packet reflex ack acks the ARRIVING sequence even while a gap is parked, so ACE prunes the lost id from its S2C cache (`AcknowledgeSequence` strictly-below) before N4 can NAK it — message-level recovery of a real loss needs N3's retail NAK-xor-ack sweep (§2.3's mutual exclusivity is load-bearing). Also noted for N4: ACE's `RejectRetransmit` consumes a fresh CLEARTEXT sequence via FlushPackets (no keystream word), so the client's gap walk parks a word for an id that never had one server-side — a real retail-vs-ACE incompatibility to resolve in N4's design (retail never assigns new sequences to cleartext). | +| N3 | complete | `0265cc42` � Opus review PASS (advisories folded into N4: transitional-state wording, SharedInit citation, pump-order wording, control-packet Time/Iteration rule, stale budget-break comment) | AckNakScheduler + 2.0 s cumulative ack (`Transport/AckNakScheduler`): ONE shared timestamp (`ReceiverData::timeStamp_` @ +0x10) arbitrating NAK-xor-ack per sweep (`ClientNet::ProcessConnection @ 0x00545450`); the ack is one cleartext exact-flags `AckSequence` carrying the tracker's `highestIDReceived_` behind the >= 2.0 s gate (`SharedNet::EnqueuePak @ 0x00543B10` — the binary's only 0x4000 construction site), armed at connection birth (`ReceiverData::Init @ 0x00548EF0`). The Phase 4.9 per-packet reflex ack and `WorldSession.SendAck` are DELETED; the `[net-tick]` acks/s probe now reads `Stats.AcksSent`. Sweep order per `FlowQueue::Empty @ 0x00548A20`: interval clock, NAK/ack arbitration, pending resends, prune. **N3 transitional state (closed by N4):** a non-empty NAK set suppressed the ack and emitted NOTHING � the exposure was real even on loopback, just low-probability: one receive-buffer drop parks an id, every later sweep takes the silent NAK branch, acks stop (witness: `[net-tick] acks/s=0`), and ACE disconnects the quiet session at its 60 s timeout. N4 completed the branch. **N1 advisory retired (fold-in):** fresh reliable sends now stamp `Header.Time` = the current interval id (`FlowQueue::TransmitNewPackets @ 0x00547A60`, header build at 0x00547A84); ACE ignores inbound `Header.Time`, so the wire is unaffected. New `WorldSession.TransportClockSource` seam drives the gate on virtual time. 723 Core.Net tests green (keepalive property proven: a quiet session's 2 s acks refresh ACE's 60 s deadline across a 120 s virtual horizon; storm collapse: a 50-packet flood → ONE ack; the model accepts the reused-sequence ack without advancing its watermark). Connected lifecycle + canonical nine-stop gates PASS. | +| N4 | complete | `852a59e3` � **Opus review PASS** (reclaim invariant attacked from five angles, held; NAK fidelity verified to the x87 masks; AP-125 filed + F1 false-arithmetic wording + F5 ordinal sentinel fixed in the acceptance commit; F3 Iteration-on-fresh-sends folds into N5) | Client NAK emission + RejectRetransmit consumption. `AckNakScheduler` completes the NAK branch: one cleartext exact-flags `RequestRetransmit` per sweep behind the STRICT 0.6 s gate on the ONE shared timestamp (`SharedNet::EnqueueNaks @ 0x00543BD0` � the 0x41-mask x87 test at 0x00543C03 proceeds only on strictly-greater, contrast the ack's >=), body u32 count + ids ascending capped at 114 (`ReceiverData::GetNaks @ 0x005490C0`, cap 0x72), borrowed sequence, never an ack in a NAK sweep. Control-header rule decided for BOTH emissions: `Time` = interval id, `Iteration` = session iteration, per the shared retail header build (`FlowQueue::TransmitNewPackets @ 0x00547A60` @ 0x00547A84); ACE reads neither. THE design piece: the AD-51 reclaimed-word pool in `InboundSequenceTracker` closes the ACE cleartext-reject keystream hazard the N2 ledger row recorded � ACE's `RejectRetransmit` consumes a fresh cleartext sequence with NO keystream word, so the gap walk mis-parks a word for it and the whole inbound stream runs one word ahead. On a VALIDATED cleartext reject (`WorldSession` calls `OnCleartextRejectSequence` post-checksum), the tracker removes the mis-park, bubble-shifts every later-drawn parked word down one position (per-word draw ordinals; ascending id ? ascending draw order), and pools the excess for the next fresh draws, consumed lowest-draw-order-first � exact for any number of interleaved rejects in any arrival order (a plain FIFO is NOT: reject-after-higher-arrival crosses the parked chain, and dual out-of-order rejects pool out of draw order � both pinned by tests). Reject BODY ids keep N2's discard (word-bearing server-side, consumed-in-place). N3 advisories all folded: honest transitional wording (above), `ReceiverData::SharedInit @ 0x00548EF0` (from `Init @ 0x00548FA0`) citation, `FlowQueue::Empty` pump-order comment (TransmitNaks ? TransmitAcks ? TransmitNewPackets, interval increment LAST @ 0x00548A9D; our clock-first order is cosmetic vs ACE), the Time/Iteration rule, and the stale `WorldSession` budget-break comment. Gate arithmetic hardened: gate ticks now round (0.6 has no exact double; truncation opened the strict gate AT the boundary). 737 Core.Net tests green, including: strict-gate boundary, shared-timestamp both directions, NAK-suppresses-ack, full wire-shape + 114-cap pins, model-served retransmission round trip, five tracker reclaim proofs, the 130-s virtual prune ? fresh-sequence reject system test (victim abandoned, later traffic decodes, pool drains to zero), 10 s long-loss (NAKs on the gate cadence, zero acks, heal inside the window), and the capstone soak: 2% seeded bidirectional loss � 10,000 messages ? zero message loss both ways, ACE crypto headroom 256 at convergence with a =250 no-erosion floor mid-flight, NAK set / reclaim pool / pending resends / ACE out-of-order buffer all zero, cache at the single watermark entry (retail Flush prunes STRICTLY below the ack). Soak notes: ACE never NAKs a quiet client (�3 row 1), so convergence keeps a C2S trickle flowing � a real idle-client tail loss heals only on the next action, an ACE constraint outside N4's scope. | +| N5 | complete | `4e290f00` � **Opus review PASS** (structural absence + arming gate + un-gameability + teardown all verified; ledger arithmetic reconciled). Acceptance folded in the review's gate strengthenings: per-direction recovery conjunction + the three keystream-health invariants (cksum-fail/sanity-drop/uncached-nak == 0) + the EnterWorldBody unrecoverable-tail caveat. Revert: `git revert 4e290f00d86ebd320d2da609fd7cd15d7175c4f0`. Test-collection hygiene (static NetDiagnostics mutation) folds into N6 | Loss observability + the LossyTransportDecorator + the connected loss gate � the permanent removal of the loopback blindness (�1). `[net-tick]` gains `resend/s nak-out/s nak-in/s rej-in/s dup-drop/s parked/s reclaim/s cache= nakset=` (window deltas mirroring acks/s; `TransportStats` gains `RejectsReceived`; string work probe-gated, counters unconditional) and `WorldSession.Dispose` emits one cumulative `[net-final]` totals line so the gate asserts exact counters, not rounded rates. N4-review F3 folded: fresh reliable sends stamp `Iteration` = the session iteration through the same shared retail header build already cited for `Time` and the N4 control packets (`FlowQueue::TransmitNewPackets @ 0x00547A60`, the build at 0x00547A84/0x00547AA8) � the control-header rule now holds across all three send shapes; ACE reads neither field inbound. `Transport/LossyTransportDecorator`: deterministic seeded per-direction loss (`ACDREAM_NET_DROP_PCT`/`_SEED`/`_DIR` via `NetDiagnostics` typed properties, Rule 5), armed only after the first ENCRYPTED outbound datagram is forwarded (parse-free flags-word check � the cleartext handshake always survives; handshake loss belongs to N6), structurally absent at 0% (`WrapIfConfigured` returns the raw transport; the default factory is the only production seam). The logoff-confirmation wait now runs the transport sweep � retail's pump (`Client::UseTime @ 0x00411C40`) never stops before `LogOffServer`, and the loss gate exposed that a dropped S2C confirmation was gap-detected but never NAKed during `Dispose`. `tools/run-connected-loss-gate.ps1` (default 2%/seed 1) runs the standard lifecycle route through the decorator vs local ACE and FAILS unless `[net-final]` shows resends>0 OR nak-out>0 OR nak-in>0 AND the decorator's own dropped ledger is non-zero � a loss gate that never dropped proves nothing, asserted explicitly. The lifecycle gate defensively clears the drop vars (decorator-absent baseline). **First loss-observing gate evidence (2026-07-29, 2%/seed 1, local ACE):** decorator dropped out=3 in=10 of forwarded out=183 in=496; `[net-final] resends=2 nak-in=2 nak-out=6 rej-in=0 acks-out=114 acks-in=119 dup-drop=0 sanity-drop=0 cksum-fail=0 parked=9 reclaimed=0 uncached-nak=0 cache=1 nakset=0` � both recovery directions fired on a real connected route (ACE NAK ? cached resend; client gap-walk park ? NAK ? ACE retransmit), all six checkpoints validated, graceful logout confirmed, ACE recorded the transport Disconnect, RESULT=PASS. The gate immediately paid for itself: it exposed that the Dispose logoff-confirmation wait processed inbound but never swept the transport, so a lost S2C confirmation could be gap-detected yet never NAKed � fixed by running the sweep in that third blocking pump (retail's `Client::UseTime @ 0x00411C40` pump runs until `LogOffServer`). Known tail caveat recorded in the gate header: a drop landing on the single-shot logoff request or transport Disconnect (~pct each) is unrecoverable by ACE's arrival-driven NAK design (�3 row 1) � rerun with another seed, never widen teardown tolerances. #261 filed for `LinkStatusSnapshot.PacketLossPercentage` (retail `CLinkStatusAverages` formula required; inventing a ratio forbidden). 747 Core.Net tests green (decorator determinism/direction/arming/structural-absence, the 5% seeded WorldSession lossy lifecycle with zero message loss + Headroom 256, `[net-tick]` field pins, Iteration-stamp pins). | +| N6 | complete | `f9c5e47e` � **Opus review PASS** (all six retail address claims verified incl. the three distinct gate strictness masks; packet-identity, latch, TTL, and ring all clean). Acceptance settles LOW-2 (TS-58/TS-59/TS-60/TS-61/AP-126 filed) + INFO-4 (DropAll resets the completed ring) + INFO-5 (the post-acceptance retry drop is NetworkManager's pre-route, not CheckState � same silent pre-CRC outcome). LOW-1 noted: retry cadence dilates to ~0.5 s via the pump's 250 ms receive granularity � mechanism/constant/strictness retail-exact, fewer retries than retail, harmless. Revert: `git revert f9c5e47e`. | ConnectResponse handshake retransmit + fragment-assembler eviction � the final implementation slice. **Retransmit:** while unconfirmed, the Connect character-list pump resends the IDENTICAL cleartext ConnectResponse (same sequence 1, same cookie, the one encoded datagram � no new outbound state) on retail's strict 0.333333333 s gate (`ClientNet::ProcessConnection @ 0x00545450` case `cs_ConnectionRequestAcked` at 0x0054547B, the constant at 0x00545481, the mask-0x41 strictly-greater test at 0x0054548C; `ClientNet::SendConnectAck @ 0x005440F0` re-stamps `lastSentHandshake_` at 0x00544102 and rebuilds the same cookie packet). Confirmation = the first checksum-valid post-negotiation packet without the ConnectRequest flag, retail's `cs_ConnectionRequestAcked ? cs_Connected` edge (`ClientNet::ProcessPacket @ 0x00545100`: the 0x40000 exclusion at 0x0054514E, `SetConnectionState(..., 5)` at 0x00545160). The cadence rides the TransportClock (virtual-clock testable via `TransportClockSource`); the Connect deadline stays wall-clock. ACE-safety pinned against the N0 model: a duplicate while still `AuthConnectResponse` re-routes idempotently through NetworkManager's pre-route; after acceptance `CheckState` clause 2 drops it pre-CRC at zero keystream cost. Pre-N6 a lost ConnectResponse was a hang to the Connect deadline � routine on a real path, and the N5 decorator deliberately arms after this window, so nothing covered it. **Assembler eviction (AD-52):** partials evict 60 s after their last accepted fragment (re-stamp-on-update per retail `ArrivedEphInfo::UpdateNetBlobID @ 0x0054AE00`), swept from `ReliableTransport.Sweep` on retail's 5 s flush cadence (`Indicator::FlushTimedOutEphInfo @ 0x0054A3D0`, gate at 0x0054A3DC; per-entry `fTimedOut @ 0x0054AE30`) � N4's RejectRetransmit abandonment had made an unrecoverable partial a reachable permanent state. A 64-entry completed-sequence ring drops late duplicates of already-completed messages instead of re-partialing them (the completed-then-duplicate leak). 60 s is a floor, never a tunable to shrink. **Fold-ins:** N5-review LOW-5 � `NetProbeTests` + `LossyTransportDecoratorTests` (the static-`NetDiagnostics`/`Console.SetOut` mutators) share one `DisableParallelization` xunit collection so they never run alongside classes constructing `WorldSession`. 757 Core.Net tests green (drop-first-ConnectResponse-retry-heals with exactly one retry and none after confirmation; clean handshake sends exactly one; server-responses-lost retries drop harmlessly at the model while the N2/N4 gap-walk ? NAK ? cached-retransmit path heals the handshake responses; model-level duplicate-after-acceptance CheckState pin; assembler TTL floor boundary/refresh-on-update/ring-drop/ring-bound; transport-level sweep eviction). Connected lifecycle gate PASS (capped six-checkpoint route + uncapped reconnect, graceful exits, zero failures). The N5-STRENGTHENED loss gate PASS on its first live run (2%/seed 1, local ACE): decorator `[net-loss] dropped out=3 in=10 forwarded out=181 in=496 armed=True`; `[net-final] resends=1 nak-in=1 nak-out=5 rej-in=0 acks-out=114 acks-in=116 dup-drop=0 sanity-drop=0 cksum-fail=0 parked=8 reclaimed=0 uncached-nak=0 cache=1 nakset=0` � the per-direction recovery conjunction held (C2S: resends+nak-in > 0; S2C: nak-out > 0), all three keystream-health invariants zero, ledger converged at the single watermark cache entry. |