diff --git a/Hologram/HologramCloud.py b/Hologram/HologramCloud.py
index f2bf44d..6bd7229 100755
--- a/Hologram/HologramCloud.py
+++ b/Hologram/HologramCloud.py
@@ -12,7 +12,6 @@
 import json
 import sys
 from Hologram.CustomCloud import CustomCloud
-from HologramAuth import TOTPAuthentication, SIMOTPAuthentication
 from Hologram.Authentication import CSRPSKAuthentication
 from Exceptions.HologramError import HologramError
 
@@ -40,9 +39,7 @@
 class HologramCloud(CustomCloud):
 
     _authentication_handlers = {
-        'csrpsk' : CSRPSKAuthentication.CSRPSKAuthentication,
-        'totp' : TOTPAuthentication.TOTPAuthentication,
-        'sim-otp' : SIMOTPAuthentication.SIMOTPAuthentication,
+        'csrpsk' : CSRPSKAuthentication.CSRPSKAuthentication
     }
 
     _errorCodeDescription = {
@@ -60,7 +57,7 @@ class HologramCloud(CustomCloud):
     }
 
     def __init__(self, credentials, enable_inbound=False, network='',
-                 authentication_type='totp'):
+                 authentication_type='csrpsk'):
         super().__init__(credentials,
                          send_host=HOLOGRAM_HOST_SEND,
                          send_port=HOLOGRAM_PORT_SEND,
@@ -71,9 +68,6 @@ def __init__(self, credentials, enable_inbound=False, network='',
 
         self.setAuthenticationType(credentials, authentication_type=authentication_type)
 
-        if self.authenticationType == 'totp':
-            self.__populate_totp_credentials()
-
     # EFFECTS: Authentication Configuration
     def setAuthenticationType(self, credentials, authentication_type='csrpsk'):
 
@@ -91,10 +85,6 @@ def sendMessage(self, message, topics=None, timeout=DEFAULT_SEND_MESSAGE_TIMEOUT
             self.addPayloadToBuffer(message)
             return ''
 
-        # Set the appropriate credentials required for sim otp authentication.
-        if self.authenticationType == 'sim-otp':
-            self.__populate_sim_otp_credentials()
-
         modem_type = None
         modem_id = None
         if self.network is not None:
@@ -119,21 +109,6 @@ def __parse_result(self, result):
 
         return resultList[0]
 
-    def __populate_totp_credentials(self):
-        try:
-            self.authentication.credentials['device_id'] = self.network.iccid
-            self.authentication.credentials['private_key'] = self.network.imsi
-        except Exception as e:
-            self.logger.error('Unable to fetch device id or private key')
-
-    def __populate_sim_otp_credentials(self):
-        nonce = self.request_hex_nonce()
-        command = self.authentication.generate_sim_otp_command(imsi=self.network.imsi,
-                                                               iccid=self.network.iccid,
-                                                               nonce=nonce)
-        modem_response = self.network.get_sim_otp_response(command)
-        self.authentication.generate_sim_otp_token(modem_response)
-
     def sendSMS(self, destination_number, message):
 
         self.__enforce_authentication_type_supported_for_sms()
diff --git a/requirements.txt b/requirements.txt
index 573eedc..af2a3b8 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -3,7 +3,6 @@ mock~=3.0.5
 pyroute2==0.5.*
 pyserial~=3.4.0
 python-pppd==1.0.3
-python-sdk-auth~=0.3.0
 pyudev~=0.21.0
 pyusb~=1.0.2
 psutil~=5.6.3