diff --git a/pySim/transport/__init__.py b/pySim/transport/__init__.py
index e69de29..c9715fc 100644
--- a/pySim/transport/__init__.py
+++ b/pySim/transport/__init__.py
@@ -0,0 +1,69 @@
+#!/usr/bin/env python
+# -*- coding: utf-8 -*-
+
+""" pySim: PCSC reader transport link base
+"""
+
+#
+# Copyright (C) 2009-2010  Sylvain Munaut <tnt@246tNt.com>
+#
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 2 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+#
+
+class LinkBase(object):
+
+	def reset_card(self):
+		"""reset_card(): Resets the card (power down/up)
+		"""
+		pass
+
+	def send_apdu_raw(self, pdu):
+		"""send_apdu_raw(pdu): Sends an APDU with minimal processing
+
+		   pdu    : string of hexadecimal characters (ex. "A0A40000023F00")
+		   return : tuple(data, sw), where
+		            data : string (in hex) of returned data (ex. "074F4EFFFF")
+		            sw   : string (in hex) of status word (ex. "9000")
+		"""
+		pass
+
+	def send_apdu(self, pdu):
+		"""send_apdu(pdu): Sends an APDU and auto fetch response data
+
+		   pdu    : string of hexadecimal characters (ex. "A0A40000023F00")
+		   return : tuple(data, sw), where
+		            data : string (in hex) of returned data (ex. "074F4EFFFF")
+		            sw   : string (in hex) of status word (ex. "9000")
+		"""
+		data, sw = self.send_apdu_raw(pdu)
+
+		if (sw is not None) and (sw[0:2] == '9f'):
+			pdu_gr = pdu[0:2] + 'c00000' + sw[2:4]
+			data, sw = self.send_apdu_raw(pdu_gr)
+
+		return data, sw
+
+	def send_apdu_checksw(self, pdu, sw="9000"):
+		"""send_apdu_checksw(pdu,sw): Sends an APDU and check returned SW
+
+		   pdu    : string of hexadecimal characters (ex. "A0A40000023F00")
+		   sw     : string of 4 hexadecimal characters (ex. "9000")
+		   return : tuple(data, sw), where
+		            data : string (in hex) of returned data (ex. "074F4EFFFF")
+		            sw   : string (in hex) of status word (ex. "9000")
+		"""
+		rv = self.send_apdu(pdu)
+		if sw.lower() != rv[1]:
+			raise RuntimeError("SW match failed ! Expected %s and got %s." % (sw.lower(), rv[1]))
+		return rv