diff --git a/netconf/nc_common/__init__.py b/netconf/nc_common/__init__.py
new file mode 100644
index 0000000..7398217
--- /dev/null
+++ b/netconf/nc_common/__init__.py
@@ -0,0 +1,44 @@
+# -*- coding: utf-8 -*-#
+#
+# December 23 2014, Christian Hopps <chopps@gmail.com>
+#
+# Copyright (c) 2015, Deutsche Telekom AG
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+from __future__ import absolute_import, division, unicode_literals, print_function, nested_scopes
+from lxml.etree import register_namespace
+
+MAXSSHBUF = 16 * 1024
+NSMAP = { }
+
+
+def nsmap_add (prefix, namespace):
+    "Add a prefix namespace mapping to the modules mapping dictionary"
+    NSMAP[prefix] = namespace
+    register_namespace(prefix, namespace)
+
+
+def nsmap_update (nsdict):
+    "Add a dicitonary of prefx namespace mappings to the modules mapping dictionary"
+    NSMAP.update(nsdict)
+    for key, val in nsdict.items():
+        register_namespace(key, val)
+
+
+def qmap (key):
+    return "{" + NSMAP[key] + "}"
+
+
+# Add base spec namespace
+nsmap_add('nc', "urn:ietf:params:xml:ns:netconf:base:1.0")
diff --git a/netconf/nc_common/error.py b/netconf/nc_common/error.py
new file mode 100644
index 0000000..802cbe9
--- /dev/null
+++ b/netconf/nc_common/error.py
@@ -0,0 +1,195 @@
+#!/usr/bin/env python
+#
+# Copyright 2016 the original author or authors.
+#
+# Adapted from https://github.com/choppsv1/netconf/error.py
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+from netconf.constants import Constants as C
+from lxml import etree
+
+class Error(Exception):
+
+    ###	Tag ###
+    IN_USE = "in-use"
+    INVALID_VALUE = "invalid-value"
+    TOO_BIG = "too-big"
+    MISSING_ATTRIBUTE = "missing-attribute"
+    BAD_ATTRIBUTE = "bad-attribute"
+    UNKNOWN_ATTRIBUTE = "unknown-attribute"
+    MISSING_ELEMENT = "missing-element"
+    BAD_ELEMENT = "bad-element"
+    UNKNOWN_ELEMENT = "unknown-element"
+    UNKNOWN_NAMESPACE = "unknown-namespace"
+    ACCESS_DENIED = "access-denied"
+    LOCK_DENIED = "lock-denied"
+    RESOURCE_DENIED = "resource-denied"
+    ROLLBACK_FAILED = "rollback-failed"
+    DATA_EXISTS = "data-exists"
+    DATA_MISSING = "data-missing"
+    OPERATION_NOT_SUPPORTED = "operation-not-supported"
+    OPERATION_FAILED = "operation-failed"
+    MALFORMED_MESSAGE = "malformed-message"
+
+    ###  Error-type ###
+    TRANSPORT = 0
+    RPC = 1
+    PROTOCOL = 2
+    APPLICATION = 3
+    ERROR_TYPE_ENUM = {
+        TRANSPORT: "transport",
+        RPC: "rpc",
+        PROTOCOL: "protocol",
+        APPLICATION: "application"
+    }
+
+    ###  Severity  ###
+    ERROR = "error"
+    WARNING = "warning"
+
+    ### Error-info ###
+    BAD_ATTRIBUTE_INFO = "bad-attribute"
+    BAD_ELEMENT_INFO = "bad-element"
+    SESSION_ID_INFO = "session-id"
+    OK_ELEMENT_INFO = "ok-element"
+    ERR_ELEMENT_INFO = "err-element"
+    NOOP_ELEMENT_INFO = "noop-element"
+
+    ### XML Error tags ###
+    XML_ERROR_TYPE = "error-type"
+    XML_ERROR_TAG = "error-tag"
+    XML_ERROR_SEV = "error-severity"
+
+
+    # def __init__(self, replynode=None, error_type=None, error_tag=None,
+    #              error_severity=None, error_tag_app=None, error_path=None,
+    #              error_message=None):
+    #
+    #     self.replynode = replynode
+    #     self.error_type = error_type
+    #     self.error_tag = error_tag
+    #     self.error_severity = error_severity
+    #     self.error_tag_app = error_tag_app
+    #     self.error_path = error_path
+    #     self.error_message = error_message
+    #     self.error_info = []
+
+class ChannelClosed(Error):
+    pass
+
+class FramingError(Error):
+    pass
+
+class SessionError(Error):
+    pass
+
+
+class RPCError(Error):
+    def __init__(self, origmsg, error_type, error_tag, **kwargs):
+        # Create the rpc reply
+        # Append original attributes and namespace
+        self.reply = etree.Element(C.RPC_REPLY,
+                                   attrib=origmsg.attrib,
+                                   nsmap=origmsg.nsmap)
+
+        rpcerr = etree.SubElement(self.reply, C.RPC_ERROR)
+
+        if error_type in Error.ERROR_TYPE_ENUM:
+            error_type = Error.ERROR_TYPE_ENUM[error_type]
+        else:
+            error_type = Error.ERROR_TYPE_ENUM[Error.RPC]
+
+        etree.SubElement(rpcerr, Error.XML_ERROR_TYPE).text = str(error_type)
+
+        etree.SubElement(rpcerr, Error.XML_ERROR_TAG).text = error_tag
+
+        if "severity" not in kwargs:
+            etree.SubElement(rpcerr, Error.XML_ERROR_SEV).text = "error"
+
+        # Convert all remaining arguments to xml
+        for key, value in kwargs.items():
+            key = key.replace('_', '-')
+            etree.SubElement(rpcerr, "error-{}".format(key)).text = str(value)
+
+        # super(RPCError, self).__init__(self.get_xml_reply())
+
+    def get_xml_reply(self):
+        return etree.tounicode(self.reply)
+
+
+class BadMsg(RPCError):
+    def __init__(self, origmsg):
+        RPCError.__init__(self,
+                          origmsg,
+                          Error.RPC,
+                          Error.MALFORMED_MESSAGE)
+
+
+class InvalidValue(Error):
+    def __init__(self, origmsg, **kwargs):
+        RPCError.__init__(self,
+                          origmsg,
+                          Error.RPC,
+                          Error.INVALID_VALUE,
+                          **kwargs)
+
+
+class MissingElement(RPCError):
+    def __init__(self, origmsg, tag, **kwargs):
+        RPCError.__init__(self,
+                          origmsg,
+                          Error.RPC,
+                          Error.MISSING_ELEMENT,
+                          info=tag,
+                          **kwargs)
+
+
+class BadElement(RPCError):
+    def __init__(self, origmsg, element, **kwargs):
+        RPCError.__init__(self,
+                          origmsg,
+                          Error.RPC,
+                          Error.BAD_ELEMENT,
+                          info=element.tag,
+                          **kwargs)
+
+
+class UnknownElement(RPCError):
+    def __init__(self, origmsg, element, **kwargs):
+        RPCError.__init__(self,
+                          origmsg,
+                          Error.RPC,
+                          Error.UNKNOWN_ELEMENT,
+                          info=element.tag,
+                          **kwargs)
+
+
+class NotImpl(RPCError):
+    def __init__(self, origmsg, **kwargs):
+        RPCError.__init__(self,
+                          origmsg,
+                          Error.PROTOCOL,
+                          Error.OPERATION_NOT_SUPPORTED,
+                          **kwargs)
+
+
+class ServerException(RPCError):
+    def __init__(self, origmsg, exception, **kwargs):
+        RPCError.__init__(self,
+                          origmsg,
+                          Error.PROTOCOL,
+                          Error.OPERATION_FAILED,
+                          info=str(exception),
+                          **kwargs)
+