diff --git a/minecraft/networking/connection.py b/minecraft/networking/connection.py
index 659a6e2..4e71c00 100644
--- a/minecraft/networking/connection.py
+++ b/minecraft/networking/connection.py
@@ -335,11 +335,12 @@ class PacketReactor(object):
             packet_data.reset_cursor()
 
             if self.connection.options.compression_enabled:
-                compressed_size = VarInt.read(packet_data)
-
-                if compressed_size > 0:
-                    decompressed_packet = decompress(
-                        packet_data.read(compressed_size))
+                decompressed_size = VarInt.read(packet_data)
+                if decompressed_size > 0:
+                    decompressed_packet = decompress(packet_data.read())
+                    assert len(decompressed_packet) == decompressed_size, \
+                        'decompressed length %d, but expected %d' % \
+                        (len(decompressed_packet), decompressed_size)
                     packet_data.reset()
                     packet_data.send(decompressed_packet)
                     packet_data.reset_cursor()
diff --git a/minecraft/networking/packets.py b/minecraft/networking/packets.py
index 5b31fea..4a71ddd 100644
--- a/minecraft/networking/packets.py
+++ b/minecraft/networking/packets.py
@@ -18,10 +18,10 @@ class PacketBuffer(object):
         """
         self.bytes.write(value)
 
-    def read(self, length):
+    def read(self, length=None):
         return self.bytes.read(length)
 
-    def recv(self, length):
+    def recv(self, length=None):
         return self.read(length)
 
     def reset(self):
@@ -123,10 +123,11 @@ class Packet(object):
         if compression_threshold is not None:
             if len(packet_buffer.get_writable()) > compression_threshold != -1:
                 # compress the current payload
-                compressed_data = compress(packet_buffer.get_writable())
+                packet_data = packet_buffer.get_writable()
+                compressed_data = compress(packet_data)
                 packet_buffer.reset()
-                # write out the length of the compressed payload
-                VarInt.send(len(compressed_data), packet_buffer)
+                # write out the length of the uncompressed payload
+                VarInt.send(len(packet_data), packet_buffer)
                 # write the compressed payload itself
                 packet_buffer.send(compressed_data)
             else: