feat(edge,protocol,test): add configurable edge bind address and expand flow-control test coverage

2026-03-16 23:35:02 +00:00
parent 982f648928
commit 17d1a795cd
8 changed files with 636 additions and 3 deletions
--- a/changelog.md
+++ b/changelog.md
@@ -1,5 +1,13 @@
 # Changelog

+## 2026-03-16 - 4.7.0 - feat(edge,protocol,test)
+add configurable edge bind address and expand flow-control test coverage
+
+- adds an optional bindAddress configuration for edge TCP listeners, defaulting to 0.0.0.0 when not provided
+- passes bindAddress through the TypeScript edge client and Rust edge runtime so local test setups can bind to localhost
+- adds protocol unit tests for adaptive stream window sizing and window update frame encoding/decoding
+- introduces end-to-end flow-control tests and updates the test script to build before running tests
+
 ## 2026-03-16 - 4.6.1 - fix(remoteingress-core)
 avoid spurious tunnel disconnect events and increase control channel capacity

--- a/package.json
+++ b/package.json
@@ -9,7 +9,7 @@
  "author": "Task Venture Capital GmbH",
  "license": "MIT",
  "scripts": {
-    "test": "(tstest test/ --verbose --logfile --timeout 60)",
+    "test": "(pnpm run build && tstest test/ --verbose --logfile --timeout 60)",
    "build": "(tsbuild tsfolders --allowimplicitany && tsrust)",
    "buildDocs": "(tsdoc)"
  },
--- a/rust/crates/remoteingress-core/src/edge.rs
+++ b/rust/crates/remoteingress-core/src/edge.rs
@@ -32,6 +32,10 @@ pub struct EdgeConfig {
    pub hub_port: u16,
    pub edge_id: String,
    pub secret: String,
+    /// Optional bind address for TCP listeners (defaults to "0.0.0.0").
+    /// Useful for testing on localhost where edge and upstream share the same machine.
+    #[serde(default)]
+    pub bind_address: Option<String>,
 }

 /// Handshake config received from hub after authentication.
@@ -416,6 +420,7 @@ async fn connect_to_hub_and_run(

    // Start TCP listeners for initial ports (hot-reloadable)
    let mut port_listeners: HashMap<u16, JoinHandle<()>> = HashMap::new();
+    let bind_address = config.bind_address.as_deref().unwrap_or("0.0.0.0");
    apply_port_config(
        &handshake.listen_ports,
        &mut port_listeners,
@@ -426,6 +431,7 @@ async fn connect_to_hub_and_run(
        next_stream_id,
        &config.edge_id,
        connection_token,
+        bind_address,
    );

    // Heartbeat: liveness timeout detects silent hub failures
@@ -492,6 +498,7 @@ async fn connect_to_hub_and_run(
                                        next_stream_id,
                                        &config.edge_id,
                                        connection_token,
+                                        bind_address,
                                    );
                                }
                            }
@@ -557,6 +564,7 @@ fn apply_port_config(
    next_stream_id: &Arc<AtomicU32>,
    edge_id: &str,
    connection_token: &CancellationToken,
+    bind_address: &str,
 ) {
    let new_set: std::collections::HashSet<u16> = new_ports.iter().copied().collect();
    let old_set: std::collections::HashSet<u16> = port_listeners.keys().copied().collect();
@@ -579,8 +587,9 @@ fn apply_port_config(
        let edge_id = edge_id.to_string();
        let port_token = connection_token.child_token();

+        let bind_addr = bind_address.to_string();
        let handle = tokio::spawn(async move {
-            let listener = match TcpListener::bind(("0.0.0.0", port)).await {
+            let listener = match TcpListener::bind((bind_addr.as_str(), port)).await {
                Ok(l) => l,
                Err(e) => {
                    log::error!("Failed to bind port {}: {}", port, e);
@@ -840,6 +849,7 @@ mod tests {
            hub_port: 9999,
            edge_id: "e1".to_string(),
            secret: "sec".to_string(),
+            bind_address: None,
        };
        let json = serde_json::to_string(&config).unwrap();
        let back: EdgeConfig = serde_json::from_str(&json).unwrap();
@@ -955,6 +965,7 @@ mod tests {
            hub_port: 8443,
            edge_id: "test-edge".to_string(),
            secret: "test-secret".to_string(),
+            bind_address: None,
        });
        let status = edge.get_status().await;
        assert!(!status.running);
@@ -971,6 +982,7 @@ mod tests {
            hub_port: 8443,
            edge_id: "e".to_string(),
            secret: "s".to_string(),
+            bind_address: None,
        });
        let rx1 = edge.take_event_rx().await;
        assert!(rx1.is_some());
@@ -985,6 +997,7 @@ mod tests {
            hub_port: 8443,
            edge_id: "e".to_string(),
            secret: "s".to_string(),
+            bind_address: None,
        });
        edge.stop().await; // should not panic
        let status = edge.get_status().await;
--- a/rust/crates/remoteingress-protocol/Cargo.toml
+++ b/rust/crates/remoteingress-protocol/Cargo.toml
@@ -5,3 +5,6 @@ edition = "2021"

 [dependencies]
 tokio = { version = "1", features = ["io-util"] }
+
+[dev-dependencies]
+tokio = { version = "1", features = ["io-util", "macros", "rt"] }
--- a/rust/crates/remoteingress-protocol/src/lib.rs
+++ b/rust/crates/remoteingress-protocol/src/lib.rs
@@ -345,4 +345,134 @@ mod tests {
        assert_eq!(&pong[0..4], &0u32.to_be_bytes());
        assert_eq!(pong.len(), FRAME_HEADER_SIZE);
    }
+
+    // --- compute_window_for_stream_count tests ---
+
+    #[test]
+    fn test_adaptive_window_zero_streams() {
+        // 0 streams treated as 1: 32MB/1 = 32MB → clamped to 4MB max
+        assert_eq!(compute_window_for_stream_count(0), INITIAL_STREAM_WINDOW);
+    }
+
+    #[test]
+    fn test_adaptive_window_one_stream() {
+        // 32MB/1 = 32MB → clamped to 4MB max
+        assert_eq!(compute_window_for_stream_count(1), INITIAL_STREAM_WINDOW);
+    }
+
+    #[test]
+    fn test_adaptive_window_at_max_boundary() {
+        // 32MB/8 = 4MB = exactly INITIAL_STREAM_WINDOW
+        assert_eq!(compute_window_for_stream_count(8), INITIAL_STREAM_WINDOW);
+    }
+
+    #[test]
+    fn test_adaptive_window_just_below_max() {
+        // 32MB/9 = 3,728,270 — first value below INITIAL_STREAM_WINDOW
+        let w = compute_window_for_stream_count(9);
+        assert!(w < INITIAL_STREAM_WINDOW);
+        assert_eq!(w, (32 * 1024 * 1024u64 / 9) as u32);
+    }
+
+    #[test]
+    fn test_adaptive_window_16_streams() {
+        // 32MB/16 = 2MB
+        assert_eq!(compute_window_for_stream_count(16), 2 * 1024 * 1024);
+    }
+
+    #[test]
+    fn test_adaptive_window_100_streams() {
+        // 32MB/100 = 335,544 bytes (~327KB)
+        let w = compute_window_for_stream_count(100);
+        assert_eq!(w, (32 * 1024 * 1024u64 / 100) as u32);
+        assert!(w > 64 * 1024); // above floor
+        assert!(w < INITIAL_STREAM_WINDOW as u32); // below ceiling
+    }
+
+    #[test]
+    fn test_adaptive_window_200_streams() {
+        // 32MB/200 = 167,772 bytes (~163KB), above 64KB floor
+        let w = compute_window_for_stream_count(200);
+        assert_eq!(w, (32 * 1024 * 1024u64 / 200) as u32);
+        assert!(w > 64 * 1024);
+    }
+
+    #[test]
+    fn test_adaptive_window_500_streams() {
+        // 32MB/500 = 67,108 bytes (~65.5KB), just above 64KB floor
+        let w = compute_window_for_stream_count(500);
+        assert_eq!(w, (32 * 1024 * 1024u64 / 500) as u32);
+        assert!(w > 64 * 1024);
+    }
+
+    #[test]
+    fn test_adaptive_window_at_min_boundary() {
+        // 32MB/512 = 65,536 = exactly 64KB floor
+        assert_eq!(compute_window_for_stream_count(512), 64 * 1024);
+    }
+
+    #[test]
+    fn test_adaptive_window_below_min_clamped() {
+        // 32MB/513 = 65,408 → clamped up to 64KB
+        assert_eq!(compute_window_for_stream_count(513), 64 * 1024);
+    }
+
+    #[test]
+    fn test_adaptive_window_1000_streams() {
+        // 32MB/1000 = 33,554 → clamped to 64KB
+        assert_eq!(compute_window_for_stream_count(1000), 64 * 1024);
+    }
+
+    #[test]
+    fn test_adaptive_window_max_u32() {
+        // Extreme: u32::MAX streams → tiny value → clamped to 64KB
+        assert_eq!(compute_window_for_stream_count(u32::MAX), 64 * 1024);
+    }
+
+    #[test]
+    fn test_adaptive_window_monotonically_decreasing() {
+        // Window should decrease (or stay same) as stream count increases
+        let mut prev = compute_window_for_stream_count(1);
+        for n in [2, 5, 10, 50, 100, 200, 500, 512, 1000] {
+            let w = compute_window_for_stream_count(n);
+            assert!(w <= prev, "window increased from {} to {} at n={}", prev, w, n);
+            prev = w;
+        }
+    }
+
+    #[test]
+    fn test_adaptive_window_total_budget_bounded() {
+        // active × per_stream_window should never exceed 32MB (+ clamp overhead for high N)
+        for n in [1, 10, 50, 100, 200, 500] {
+            let w = compute_window_for_stream_count(n);
+            let total = w as u64 * n as u64;
+            assert!(total <= 32 * 1024 * 1024, "total {}MB exceeds budget at n={}", total / (1024*1024), n);
+        }
+    }
+
+    // --- encode/decode window_update roundtrip ---
+
+    #[test]
+    fn test_window_update_roundtrip() {
+        for &increment in &[0u32, 1, 64 * 1024, INITIAL_STREAM_WINDOW, MAX_WINDOW_SIZE, u32::MAX] {
+            let frame = encode_window_update(42, FRAME_WINDOW_UPDATE, increment);
+            assert_eq!(frame[4], FRAME_WINDOW_UPDATE);
+            let decoded = decode_window_update(&frame[FRAME_HEADER_SIZE..]);
+            assert_eq!(decoded, Some(increment));
+        }
+    }
+
+    #[test]
+    fn test_window_update_back_roundtrip() {
+        let frame = encode_window_update(7, FRAME_WINDOW_UPDATE_BACK, 1234567);
+        assert_eq!(frame[4], FRAME_WINDOW_UPDATE_BACK);
+        assert_eq!(decode_window_update(&frame[FRAME_HEADER_SIZE..]), Some(1234567));
+    }
+
+    #[test]
+    fn test_decode_window_update_malformed() {
+        assert_eq!(decode_window_update(&[]), None);
+        assert_eq!(decode_window_update(&[0, 0, 0]), None);
+        assert_eq!(decode_window_update(&[0, 0, 0, 0, 0]), None);
+    }
 }
--- a/test/test.flowcontrol.node.ts
+++ b/test/test.flowcontrol.node.ts
@@ -0,0 +1,475 @@
+import { expect, tap } from '@push.rocks/tapbundle';
+import * as net from 'net';
+import * as crypto from 'crypto';
+import { RemoteIngressHub, RemoteIngressEdge } from '../ts/index.js';
+
+// ---------------------------------------------------------------------------
+// Helpers
+// ---------------------------------------------------------------------------
+
+/** Find N free ports by binding to port 0 and collecting OS-assigned ports. */
+async function findFreePorts(count: number): Promise<number[]> {
+  const servers: net.Server[] = [];
+  const ports: number[] = [];
+  for (let i = 0; i < count; i++) {
+    const server = net.createServer();
+    await new Promise<void>((resolve) => server.listen(0, '127.0.0.1', resolve));
+    ports.push((server.address() as net.AddressInfo).port);
+    servers.push(server);
+  }
+  await Promise.all(servers.map((s) => new Promise<void>((resolve) => s.close(() => resolve()))));
+  return ports;
+}
+
+type TrackingServer = net.Server & { destroyAll: () => void };
+
+/** Start a TCP echo server that tracks connections for force-close. */
+function startEchoServer(port: number, host: string): Promise<TrackingServer> {
+  return new Promise((resolve, reject) => {
+    const connections = new Set<net.Socket>();
+    const server = net.createServer((socket) => {
+      connections.add(socket);
+      socket.on('close', () => connections.delete(socket));
+
+      // Skip PROXY protocol v1 header line before echoing
+      let proxyHeaderParsed = false;
+      let pendingBuf = Buffer.alloc(0);
+      socket.on('data', (data: Buffer) => {
+        if (!proxyHeaderParsed) {
+          pendingBuf = Buffer.concat([pendingBuf, data]);
+          const idx = pendingBuf.indexOf('\r\n');
+          if (idx !== -1) {
+            proxyHeaderParsed = true;
+            const remainder = pendingBuf.subarray(idx + 2);
+            if (remainder.length > 0) {
+              socket.write(remainder);
+            }
+          }
+          return;
+        }
+        socket.write(data);
+      });
+      socket.on('error', () => {});
+    }) as TrackingServer;
+
+    server.destroyAll = () => {
+      for (const conn of connections) conn.destroy();
+      connections.clear();
+    };
+
+    server.on('error', reject);
+    server.listen(port, host, () => resolve(server));
+  });
+}
+
+/**
+ * Start a server that sends a large response immediately on first data received.
+ * Does NOT wait for end (the tunnel protocol has no half-close).
+ * On receiving first data chunk after PROXY header, sends responseSize bytes then closes.
+ */
+function startLargeResponseServer(port: number, host: string, responseSize: number): Promise<TrackingServer> {
+  return new Promise((resolve, reject) => {
+    const connections = new Set<net.Socket>();
+    const server = net.createServer((socket) => {
+      connections.add(socket);
+      socket.on('close', () => connections.delete(socket));
+
+      let proxyHeaderParsed = false;
+      let pendingBuf = Buffer.alloc(0);
+      let responseSent = false;
+
+      socket.on('data', (data: Buffer) => {
+        if (!proxyHeaderParsed) {
+          pendingBuf = Buffer.concat([pendingBuf, data]);
+          const idx = pendingBuf.indexOf('\r\n');
+          if (idx !== -1) {
+            proxyHeaderParsed = true;
+            const remainder = pendingBuf.subarray(idx + 2);
+            if (remainder.length > 0 && !responseSent) {
+              responseSent = true;
+              sendLargeResponse(socket, responseSize);
+            }
+          }
+          return;
+        }
+        if (!responseSent) {
+          responseSent = true;
+          sendLargeResponse(socket, responseSize);
+        }
+      });
+      socket.on('error', () => {});
+    }) as TrackingServer;
+
+    server.destroyAll = () => {
+      for (const conn of connections) conn.destroy();
+      connections.clear();
+    };
+
+    server.on('error', reject);
+    server.listen(port, host, () => resolve(server));
+  });
+}
+
+function sendLargeResponse(socket: net.Socket, totalBytes: number) {
+  const chunkSize = 32 * 1024;
+  let sent = 0;
+  const writeChunk = () => {
+    while (sent < totalBytes) {
+      const toWrite = Math.min(chunkSize, totalBytes - sent);
+      // Use a deterministic pattern for verification
+      const chunk = Buffer.alloc(toWrite, (sent % 256) & 0xff);
+      const canContinue = socket.write(chunk);
+      sent += toWrite;
+      if (!canContinue) {
+        socket.once('drain', writeChunk);
+        return;
+      }
+    }
+    socket.end();
+  };
+  writeChunk();
+}
+
+/** Force-close a server: destroy all connections, then close. */
+async function forceCloseServer(server: TrackingServer): Promise<void> {
+  server.destroyAll();
+  await new Promise<void>((resolve) => server.close(() => resolve()));
+}
+
+interface TestTunnel {
+  hub: RemoteIngressHub;
+  edge: RemoteIngressEdge;
+  edgePort: number;
+  cleanup: () => Promise<void>;
+}
+
+/**
+ * Start a full hub + edge tunnel.
+ * Edge binds to 127.0.0.1, upstream server binds to 127.0.0.2.
+ * Hub targetHost = 127.0.0.2 so hub -> upstream doesn't loop back to edge.
+ */
+async function startTunnel(edgePort: number, hubPort: number): Promise<TestTunnel> {
+  const hub = new RemoteIngressHub();
+  const edge = new RemoteIngressEdge();
+
+  await hub.start({
+    tunnelPort: hubPort,
+    targetHost: '127.0.0.2',
+  });
+
+  await hub.updateAllowedEdges([
+    { id: 'test-edge', secret: 'test-secret', listenPorts: [edgePort] },
+  ]);
+
+  const connectedPromise = new Promise<void>((resolve, reject) => {
+    const timeout = setTimeout(() => reject(new Error('Edge did not connect within 10s')), 10000);
+    edge.once('tunnelConnected', () => {
+      clearTimeout(timeout);
+      resolve();
+    });
+  });
+
+  await edge.start({
+    hubHost: '127.0.0.1',
+    hubPort,
+    edgeId: 'test-edge',
+    secret: 'test-secret',
+    bindAddress: '127.0.0.1',
+  });
+
+  await connectedPromise;
+  await new Promise((resolve) => setTimeout(resolve, 500));
+
+  return {
+    hub,
+    edge,
+    edgePort,
+    cleanup: async () => {
+      await edge.stop();
+      await hub.stop();
+    },
+  };
+}
+
+/**
+ * Send data through the tunnel and collect the echoed response.
+ */
+function sendAndReceive(port: number, data: Buffer, timeoutMs = 30000): Promise<Buffer> {
+  return new Promise((resolve, reject) => {
+    const chunks: Buffer[] = [];
+    let totalReceived = 0;
+    const expectedLength = data.length;
+    let settled = false;
+
+    const client = net.createConnection({ host: '127.0.0.1', port }, () => {
+      client.write(data);
+      client.end();
+    });
+
+    const timer = setTimeout(() => {
+      if (!settled) {
+        settled = true;
+        client.destroy();
+        reject(new Error(`Timeout after ${timeoutMs}ms — received ${totalReceived}/${expectedLength} bytes`));
+      }
+    }, timeoutMs);
+
+    client.on('data', (chunk: Buffer) => {
+      chunks.push(chunk);
+      totalReceived += chunk.length;
+      if (totalReceived >= expectedLength && !settled) {
+        settled = true;
+        clearTimeout(timer);
+        client.destroy();
+        resolve(Buffer.concat(chunks));
+      }
+    });
+
+    client.on('end', () => {
+      if (!settled) {
+        settled = true;
+        clearTimeout(timer);
+        resolve(Buffer.concat(chunks));
+      }
+    });
+
+    client.on('error', (err) => {
+      if (!settled) {
+        settled = true;
+        clearTimeout(timer);
+        reject(err);
+      }
+    });
+  });
+}
+
+/**
+ * Connect to the tunnel, send a small request, and collect a large response.
+ * Does NOT call end() — the tunnel has no half-close.
+ * Instead, collects until expectedResponseSize bytes arrive.
+ */
+function sendAndReceiveLarge(
+  port: number,
+  data: Buffer,
+  expectedResponseSize: number,
+  timeoutMs = 60000,
+): Promise<Buffer> {
+  return new Promise((resolve, reject) => {
+    const chunks: Buffer[] = [];
+    let totalReceived = 0;
+    let settled = false;
+
+    const client = net.createConnection({ host: '127.0.0.1', port }, () => {
+      client.write(data);
+      // Do NOT call client.end() — the server will respond immediately
+      // and the tunnel CLOSE will happen when the download finishes
+    });
+
+    const timer = setTimeout(() => {
+      if (!settled) {
+        settled = true;
+        client.destroy();
+        reject(new Error(`Timeout after ${timeoutMs}ms — received ${totalReceived}/${expectedResponseSize} bytes`));
+      }
+    }, timeoutMs);
+
+    client.on('data', (chunk: Buffer) => {
+      chunks.push(chunk);
+      totalReceived += chunk.length;
+      if (totalReceived >= expectedResponseSize && !settled) {
+        settled = true;
+        clearTimeout(timer);
+        client.destroy();
+        resolve(Buffer.concat(chunks));
+      }
+    });
+
+    client.on('end', () => {
+      if (!settled) {
+        settled = true;
+        clearTimeout(timer);
+        resolve(Buffer.concat(chunks));
+      }
+    });
+
+    client.on('error', (err) => {
+      if (!settled) {
+        settled = true;
+        clearTimeout(timer);
+        reject(err);
+      }
+    });
+  });
+}
+
+function sha256(buf: Buffer): string {
+  return crypto.createHash('sha256').update(buf).digest('hex');
+}
+
+// ---------------------------------------------------------------------------
+// Tests
+// ---------------------------------------------------------------------------
+
+let tunnel: TestTunnel;
+let echoServer: TrackingServer;
+let hubPort: number;
+let edgePort: number;
+
+tap.test('setup: start echo server and tunnel', async () => {
+  [hubPort, edgePort] = await findFreePorts(2);
+
+  echoServer = await startEchoServer(edgePort, '127.0.0.2');
+  tunnel = await startTunnel(edgePort, hubPort);
+
+  expect(tunnel.hub.running).toBeTrue();
+});
+
+tap.test('single stream: 32MB transfer exceeding initial 4MB window', async () => {
+  const size = 32 * 1024 * 1024;
+  const data = crypto.randomBytes(size);
+  const expectedHash = sha256(data);
+
+  const received = await sendAndReceive(edgePort, data, 60000);
+
+  expect(received.length).toEqual(size);
+  expect(sha256(received)).toEqual(expectedHash);
+});
+
+tap.test('200 concurrent streams with 64KB each', async () => {
+  const streamCount = 200;
+  const payloadSize = 64 * 1024;
+
+  const promises = Array.from({ length: streamCount }, () => {
+    const data = crypto.randomBytes(payloadSize);
+    const hash = sha256(data);
+    return sendAndReceive(edgePort, data, 30000).then((received) => ({
+      sent: hash,
+      received: sha256(received),
+      sizeOk: received.length === payloadSize,
+    }));
+  });
+
+  const results = await Promise.all(promises);
+  const failures = results.filter((r) => !r.sizeOk || r.sent !== r.received);
+
+  expect(failures.length).toEqual(0);
+});
+
+tap.test('512 concurrent streams at minimum window boundary (16KB each)', async () => {
+  const streamCount = 512;
+  const payloadSize = 16 * 1024;
+
+  const promises = Array.from({ length: streamCount }, () => {
+    const data = crypto.randomBytes(payloadSize);
+    const hash = sha256(data);
+    return sendAndReceive(edgePort, data, 60000).then((received) => ({
+      sent: hash,
+      received: sha256(received),
+      sizeOk: received.length === payloadSize,
+    }));
+  });
+
+  const results = await Promise.all(promises);
+  const failures = results.filter((r) => !r.sizeOk || r.sent !== r.received);
+
+  expect(failures.length).toEqual(0);
+});
+
+tap.test('asymmetric transfer: 4KB request -> 4MB response', async () => {
+  // Swap to large-response server
+  await forceCloseServer(echoServer);
+  const responseSize = 4 * 1024 * 1024; // 4 MB
+  const largeServer = await startLargeResponseServer(edgePort, '127.0.0.2', responseSize);
+
+  try {
+    const requestData = crypto.randomBytes(4 * 1024); // 4 KB
+    const received = await sendAndReceiveLarge(edgePort, requestData, responseSize, 60000);
+    expect(received.length).toEqual(responseSize);
+  } finally {
+    // Always restore echo server even on failure
+    await forceCloseServer(largeServer);
+    echoServer = await startEchoServer(edgePort, '127.0.0.2');
+  }
+});
+
+tap.test('100 streams x 1MB each (100MB total exceeding 32MB budget)', async () => {
+  const streamCount = 100;
+  const payloadSize = 1 * 1024 * 1024;
+
+  const promises = Array.from({ length: streamCount }, () => {
+    const data = crypto.randomBytes(payloadSize);
+    const hash = sha256(data);
+    return sendAndReceive(edgePort, data, 120000).then((received) => ({
+      sent: hash,
+      received: sha256(received),
+      sizeOk: received.length === payloadSize,
+    }));
+  });
+
+  const results = await Promise.all(promises);
+  const failures = results.filter((r) => !r.sizeOk || r.sent !== r.received);
+
+  expect(failures.length).toEqual(0);
+});
+
+tap.test('active stream counter tracks concurrent connections', async () => {
+  const N = 50;
+
+  // Open N connections and keep them alive (send data but don't close)
+  const sockets: net.Socket[] = [];
+  const connectPromises = Array.from({ length: N }, () => {
+    return new Promise<net.Socket>((resolve, reject) => {
+      const sock = net.createConnection({ host: '127.0.0.1', port: edgePort }, () => {
+        resolve(sock);
+      });
+      sock.on('error', () => {});
+      setTimeout(() => reject(new Error('connect timeout')), 5000);
+    });
+  });
+
+  const connected = await Promise.all(connectPromises);
+  sockets.push(...connected);
+
+  // Brief delay for stream registration to propagate
+  await new Promise((resolve) => setTimeout(resolve, 500));
+
+  // Verify the edge reports >= N active streams.
+  // This counter is the input to compute_window_for_stream_count(),
+  // so its accuracy determines whether adaptive window sizing is correct.
+  const status = await tunnel.edge.getStatus();
+  expect(status.activeStreams).toBeGreaterThanOrEqual(N);
+
+  // Clean up: destroy all sockets (the tunnel's 300s stream timeout will handle cleanup)
+  for (const sock of sockets) {
+    sock.destroy();
+  }
+});
+
+tap.test('50 streams x 2MB each (forces multiple window refills per stream)', async () => {
+  // At 50 concurrent streams: adaptive window = 32MB/50 = 655KB per stream
+  // Each stream sends 2MB → needs ~3 WINDOW_UPDATE refill cycles per stream
+  const streamCount = 50;
+  const payloadSize = 2 * 1024 * 1024;
+
+  const promises = Array.from({ length: streamCount }, () => {
+    const data = crypto.randomBytes(payloadSize);
+    const hash = sha256(data);
+    return sendAndReceive(edgePort, data, 120000).then((received) => ({
+      sent: hash,
+      received: sha256(received),
+      sizeOk: received.length === payloadSize,
+    }));
+  });
+
+  const results = await Promise.all(promises);
+  const failures = results.filter((r) => !r.sizeOk || r.sent !== r.received);
+
+  expect(failures.length).toEqual(0);
+});
+
+tap.test('teardown: stop tunnel and echo server', async () => {
+  await tunnel.cleanup();
+  await forceCloseServer(echoServer);
+});
+
+export default tap.start();
--- a/ts/00_commitinfo_data.ts
+++ b/ts/00_commitinfo_data.ts
@@ -3,6 +3,6 @@
 */
 export const commitinfo = {
  name: '@serve.zone/remoteingress',
-  version: '4.6.1',
+  version: '4.7.0',
  description: 'Edge ingress tunnel for DcRouter - accepts incoming TCP connections at network edge and tunnels them to DcRouter SmartProxy preserving client IP via PROXY protocol v1.'
 }
--- a/ts/classes.remoteingressedge.ts
+++ b/ts/classes.remoteingressedge.ts
@@ -14,6 +14,7 @@ type TEdgeCommands = {
      hubPort: number;
      edgeId: string;
      secret: string;
+      bindAddress?: string;
    };
    result: { started: boolean };
  };
@@ -38,6 +39,7 @@ export interface IEdgeConfig {
  hubPort?: number;
  edgeId: string;
  secret: string;
+  bindAddress?: string;
 }

 const MAX_RESTART_ATTEMPTS = 10;
@@ -132,6 +134,7 @@ export class RemoteIngressEdge extends EventEmitter {
      hubPort: edgeConfig.hubPort ?? 8443,
      edgeId: edgeConfig.edgeId,
      secret: edgeConfig.secret,
+      ...(edgeConfig.bindAddress ? { bindAddress: edgeConfig.bindAddress } : {}),
    });

    this.started = true;
@@ -227,6 +230,7 @@ export class RemoteIngressEdge extends EventEmitter {
        hubPort: this.savedConfig.hubPort ?? 8443,
        edgeId: this.savedConfig.edgeId,
        secret: this.savedConfig.secret,
+        ...(this.savedConfig.bindAddress ? { bindAddress: this.savedConfig.bindAddress } : {}),
      });

      this.started = true;