diff --git a/libp2p/libp2p.py b/libp2p/libp2p.py
index 8e4e58d..e294411 100644
--- a/libp2p/libp2p.py
+++ b/libp2p/libp2p.py
@@ -6,7 +6,7 @@ from Crypto.PublicKey import RSA
 
 class Libp2p(object):
 
-    def __init__(self, idOpt, \
+    def __init__(self, idOpt = None, \
         transportOpt = ["/ip4/127.0.0.1/tcp/10000"], \
         muxerOpt = ["mplex/6.7.0"], \
         secOpt = ["secio"], \