diff --git a/src/server.py b/src/server.py
--- a/src/server.py
+++ b/src/server.py
@@ -4,6 +4,8 @@ from networkers import NetworkReader,Net
 import collections
 import sys
 
+import config as conf
+
 # debug copy default file
 import shutil
 origFilename=sys.argv[1]
@@ -11,67 +13,74 @@ filename=origFilename+"_"
 shutil.copyfile(origFilename,filename)
 
 
+class Connection:
+	def __init__(self,server_socket):
+		self.socket, address = server_socket.accept()
+		print('Connected by', address)
+		fr=self.socket.makefile(mode="rb")
+		fw=self.socket.makefile(mode="wb")
+
+		networkReader=NetworkReader(fr)
+		networkReader.start()
+		networkWriter=NetworkWriter(fw)
+		networkWriter.start()
+
+		self.incoming=networkReader.output # synchronized message queue
+		self.outcoming=networkWriter.input
+
+	def __enter__(self):
+		return self.incoming,self.outcoming
+
+	def __exit__(self, exc_type, exc_val, exc_tb):
+		self.socket.close()
+
+
 localTree=HashTree.fromFile(open(filename,mode="rb"))
 
-HOST = ''								 # Symbolic name meaning all available interfaces
-PORT = 50009							# Arbitrary non-privileged port
-s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
-s.bind((HOST, PORT))
-s.listen(1)
-conn, addr = s.accept()
-print('Connected by', addr)
-fr=conn.makefile(mode="rb")
-fw=conn.makefile(mode="wb")
-
-networkReader=NetworkReader(fr)
-networkReader.start()
-networkWriter=NetworkWriter(fw)
-networkWriter.start()
+ss = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+ss.bind(("",conf.port))
+ss.listen(1)
 
 blocksToTransfer=[]
 nodeStack=collections.deque([0])
-incoming=networkReader.output # synchronized message queue
-outcoming=networkWriter.input
 
 i1=-1
 
 
 while True:
-	jsonData,binData=incoming.get(timeout=2)
-	dataFile=open(filename,mode="rb+")
-	
-	if jsonData["command"]=="init":
-		assert jsonData["blockSize"]==localTree.BLOCK_SIZE
-		assert jsonData["blockCount"]==localTree.leafCount
-		
-	elif jsonData["command"]=="req": # !! index out of range
-		print("received request for node #{0}".format(jsonData["index"]))
-		nodeHash=localTree.store[jsonData["index"]]
-		
-		jsonResponse={"command":"send", "index":jsonData["index"], "dataType":"hash"}
-		binResponse=nodeHash
-		
-		outcoming.put((jsonResponse,binResponse),timeout=2)
-	
-	elif jsonData["command"]=="send" and jsonData["dataType"]=="data": # needlessly allow hashes and data in mixed order
-		print("received data block #{0}: {1}...{2}".format(jsonData["index"],binData[:5],binData[-5:]))
+	with Connection(ss) as (incoming,outcoming):
+		jsonData,binData=incoming.get(timeout=2)
+		dataFile=open(filename,mode="rb+")
+
+		if jsonData["command"]=="init":
+			assert jsonData["blockSize"]==localTree.BLOCK_SIZE
+			assert jsonData["blockCount"]==localTree.leafCount
+
+		elif jsonData["command"]=="req": # !! index out of range
+			print("received request for node #{0}".format(jsonData["index"]))
+			nodeHash=localTree.store[jsonData["index"]]
+
+			jsonResponse={"command":"send", "index":jsonData["index"], "dataType":"hash"}
+			binResponse=nodeHash
+
+			outcoming.put((jsonResponse,binResponse),timeout=2)
 
-		i2=jsonData["index"]
-		if i1+1!=i2:
-			dataFile.seek(i2*localTree.BLOCK_SIZE)
-		dataFile.write(binData)
-		i1=i2
-		
-		# never update the hash tree
-		
-	elif jsonData["command"]=="end":
-		print("closing...")
-		break
+		elif jsonData["command"]=="send" and jsonData["dataType"]=="data": # needlessly allow hashes and data in mixed order
+			print("received data block #{0}: {1}...{2}".format(jsonData["index"],binData[:5],binData[-5:]))
+
+			i2=jsonData["index"]
+			if i1+1!=i2:
+				dataFile.seek(i2*localTree.BLOCK_SIZE)
+			dataFile.write(binData)
+			i1=i2
+
+			# never update the hash tree
+
+		elif jsonData["command"]=="end":
+			print("closing...")
+			break
 	
-	else: pass # !! error
+		else: pass # !! error
 
-# fr.close()
-# fw.close()
 dataFile.close()
-conn.close()
 sys.exit(0)