diff --git a/lib/net/packets.js b/lib/net/packets.js
index 2f3c5028..c07422bb 100644
--- a/lib/net/packets.js
+++ b/lib/net/packets.js
@@ -1147,6 +1147,8 @@ InvPacket.prototype.getSize = function getSize() {
 InvPacket.prototype.toWriter = function toWriter(bw) {
   var i, item;
 
+  assert(this.items.length <= 50000);
+
   bw.writeVarint(this.items.length);
 
   for (i = 0; i < this.items.length; i++) {
@@ -1178,6 +1180,8 @@ InvPacket.prototype.fromReader = function fromReader(br) {
 
   count = br.readVarint();
 
+  assert(count <= 50000, 'Inv item count too high.');
+
   for (i = 0; i < count; i++)
     this.items.push(InvItem.fromReader(br));
 
diff --git a/lib/net/peer.js b/lib/net/peer.js
index 19c65d20..70d66e1c 100644
--- a/lib/net/peer.js
+++ b/lib/net/peer.js
@@ -189,7 +189,7 @@ Peer.prototype._init = function init() {
 
   this.parser.on('packet', co(function* (packet) {
     try {
-      yield self._onPacket(packet);
+      yield self.handlePacket(packet);
     } catch (e) {
       self.destroy();
       self.error(e);
@@ -330,19 +330,16 @@ Peer.prototype.connect = function connect(port, host) {
  */
 
 Peer.prototype.open = co(function* open() {
-  yield this._wait();
-  yield this._stallify();
-  yield this._bip151();
-  yield this._bip150();
-  yield this._handshake();
-  yield this._finalize();
+  yield this.initConnect();
+  yield this.initStall();
+  yield this.initBIP151();
+  yield this.initBIP150();
+  yield this.initVerack();
+  yield this.finalize();
 
   if (this.destroyed)
     throw new Error('Peer was destroyed.');
 
-  clearTimeout(this.connectTimeout);
-  this.connectTimeout = null;
-
   // Finally we can let the pool know
   // that this peer is ready to go.
   this.emit('open');
@@ -367,7 +364,7 @@ Peer.prototype.tryOpen = co(function* tryOpen() {
  * @private
  */
 
-Peer.prototype._wait = function _wait() {
+Peer.prototype.initConnect = function initConnect() {
   var self = this;
 
   if (this.connected) {
@@ -397,7 +394,7 @@ Peer.prototype._wait = function _wait() {
  * @private
  */
 
-Peer.prototype._stallify = function _stallify() {
+Peer.prototype.initStall = function initStall() {
   var self = this;
   assert(!this.stallTimer);
   this.stallTimer = setInterval(function() {
@@ -412,7 +409,7 @@ Peer.prototype._stallify = function _stallify() {
  * @private
  */
 
-Peer.prototype._bip151 = co(function* _bip151() {
+Peer.prototype.initBIP151 = co(function* initBIP151() {
   // Send encinit. Wait for handshake to complete.
   if (!this.bip151)
     return;
@@ -442,7 +439,7 @@ Peer.prototype._bip151 = co(function* _bip151() {
  * @private
  */
 
-Peer.prototype._bip150 = co(function* _bip150() {
+Peer.prototype.initBIP150 = co(function* initBIP150() {
   if (!this.bip151 || !this.bip150)
     return;
 
@@ -475,7 +472,7 @@ Peer.prototype._bip150 = co(function* _bip150() {
  * @private
  */
 
-Peer.prototype._handshake = co(function* _handshake() {
+Peer.prototype.initVerack = co(function* initVerack() {
   // Say hello.
   this.sendVersion();
 
@@ -509,7 +506,7 @@ Peer.prototype._handshake = co(function* _handshake() {
  * @private
  */
 
-Peer.prototype._finalize = co(function* _finalize() {
+Peer.prototype.finalize = co(function* finalize() {
   var self = this;
 
   // Setup the ping interval.
@@ -591,7 +588,7 @@ Peer.prototype.announceBlock = function announceBlock(blocks) {
     // they're using compact block mode 1.
     if (this.compactMode && this.compactMode.mode === 1) {
       this.invFilter.add(block.hash());
-      this._sendCompactBlock(block, this.compactWitness);
+      this.sendCompactBlock(block, this.compactWitness);
       continue;
     }
 
@@ -1083,24 +1080,29 @@ Peer.prototype.getData = function getData(items) {
  * @param {Packet} packet
  */
 
-Peer.prototype._onPacket = co(function* onPacket(packet) {
+Peer.prototype.handlePacket = co(function* handlePacket(packet) {
   var unlock;
 
+  // We stop reads and lock the peer for any
+  // packet with significant IO/asynchronocity.
   switch (packet.type) {
-    case packetTypes.VERSION:
-    case packetTypes.CMPCTBLOCK:
-      // These can't have locks or stop reads.
-      return yield this.__onPacket(packet);
-    default:
+    case packetTypes.GETDATA:
+    case packetTypes.GETBLOCKS:
+    case packetTypes.GETHEADERS:
+    case packetTypes.GETUTXOS:
       unlock = yield this.locker.lock();
+
       this.socket.pause();
+
       try {
-        return yield this.__onPacket(packet);
+        return yield this.onPacket(packet);
       } finally {
         this.socket.resume();
         unlock();
       }
       break;
+    default:
+      return yield this.onPacket(packet);
   }
 });
 
@@ -1110,7 +1112,7 @@ Peer.prototype._onPacket = co(function* onPacket(packet) {
  * @param {Packet} packet
  */
 
-Peer.prototype.__onPacket = co(function* onPacket(packet) {
+Peer.prototype.onPacket = co(function* onPacket(packet) {
   this.lastRecv = util.ms();
 
   if (this.destroyed)
@@ -1611,11 +1613,12 @@ Peer.prototype.handleMempool = co(function* handleMempool(packet) {
 
 /**
  * Get a block/tx from the broadcast map.
+ * @private
  * @param {InvItem} item
  * @returns {Promise}
  */
 
-Peer.prototype._getBroadcasted = function _getBroadcasted(item) {
+Peer.prototype.getBroadcasted = function getBroadcasted(item) {
   var entry = this.pool.invMap[item.hash];
 
   if (!entry)
@@ -1646,12 +1649,13 @@ Peer.prototype._getBroadcasted = function _getBroadcasted(item) {
 
 /**
  * Get a block/tx either from the broadcast map, mempool, or blockchain.
+ * @private
  * @param {InvItem} item
  * @returns {Promise}
  */
 
-Peer.prototype._getItem = co(function* _getItem(item) {
-  var entry = this._getBroadcasted(item);
+Peer.prototype.getItem = co(function* getItem(item) {
+  var entry = this.getBroadcasted(item);
 
   if (entry)
     return entry;
@@ -1676,12 +1680,13 @@ Peer.prototype._getItem = co(function* _getItem(item) {
 
 /**
  * Send a block from the broadcast list or chain.
+ * @private
  * @param {InvItem} item
  * @returns {Boolean}
  */
 
-Peer.prototype._sendBlock = co(function* _sendBlock(item, witness) {
-  var block = this._getBroadcasted(item);
+Peer.prototype.sendBlock = co(function* sendBlock(item, witness) {
+  var block = this.getBroadcasted(item);
 
   // Check for a broadcasted item first.
   if (block) {
@@ -1720,12 +1725,13 @@ Peer.prototype._sendBlock = co(function* _sendBlock(item, witness) {
 
 /**
  * Send a compact block.
+ * @private
  * @param {Block} block
  * @param {Boolean} witness
  * @returns {Boolean}
  */
 
-Peer.prototype._sendCompactBlock = function _sendCompactBlock(block, witness) {
+Peer.prototype.sendCompactBlock = function sendCompactBlock(block, witness) {
   // Try again with a new nonce
   // if we get a siphash collision.
   for (;;) {
@@ -1761,7 +1767,7 @@ Peer.prototype.handleGetData = co(function* handleGetData(packet) {
     item = items[i];
 
     if (item.isTX()) {
-      tx = yield this._getItem(item);
+      tx = yield this.getItem(item);
 
       if (!tx) {
         notFound.push(item);
@@ -1788,7 +1794,7 @@ Peer.prototype.handleGetData = co(function* handleGetData(packet) {
     switch (item.type) {
       case constants.inv.BLOCK:
       case constants.inv.WITNESS_BLOCK:
-        result = yield this._sendBlock(item, item.hasWitness());
+        result = yield this.sendBlock(item, item.hasWitness());
         if (!result) {
           notFound.push(item);
           continue;
@@ -1802,7 +1808,7 @@ Peer.prototype.handleGetData = co(function* handleGetData(packet) {
           continue;
         }
 
-        block = yield this._getItem(item);
+        block = yield this.getItem(item);
 
         if (!block) {
           notFound.push(item);
@@ -1826,7 +1832,7 @@ Peer.prototype.handleGetData = co(function* handleGetData(packet) {
         // Fallback to full block.
         height = yield this.chain.db.getHeight(item.hash);
         if (height < this.chain.tip.height - 10) {
-          result = yield this._sendBlock(item, this.compactWitness);
+          result = yield this.sendBlock(item, this.compactWitness);
           if (!result) {
             notFound.push(item);
             continue;
@@ -1835,14 +1841,14 @@ Peer.prototype.handleGetData = co(function* handleGetData(packet) {
           break;
         }
 
-        block = yield this._getItem(item);
+        block = yield this.getItem(item);
 
         if (!block) {
           notFound.push(item);
           continue;
         }
 
-        yield this._sendCompactBlock(block, this.compactWitness);
+        yield this.sendCompactBlock(block, this.compactWitness);
 
         blocks++;
 
@@ -2387,7 +2393,7 @@ Peer.prototype.handleGetBlockTxn = co(function* handleGetBlockTxn(packet) {
 
   item = new InvItem(constants.inv.BLOCK, req.hash);
 
-  block = yield this._getItem(item);
+  block = yield this.getItem(item);
 
   if (!block) {
     this.logger.debug(