diff --git a/include/login.h b/include/login.h
index b82c7a95..ee4927f5 100644
--- a/include/login.h
+++ b/include/login.h
@@ -27,6 +27,12 @@ namespace AMQP {
 class Login
 {
 private:
+    /**
+     *  The login mechanism
+     *  @var LoginMechanism
+     */
+    LoginMechanism _mechanism;
+
     /**
      *  The username
      *  @var string
@@ -41,10 +47,19 @@ class Login
 
 
 public:
+    /**
+     *  Login mechanism enum
+     */
+    typedef enum
+    {
+        LOGIN_PLAIN,
+        LOGIN_EXTERNAL
+    } LoginMechanism;
+
     /**
      *  Default constructor
      */
-    Login() : _user("guest"), _password("guest") {}
+    Login() : _mechanism(LOGIN_PLAIN), _user("guest"), _password("guest") {}
 
     /**
      *  Constructor
@@ -52,7 +67,12 @@ class Login
      *  @param  password
      */
     Login(std::string user, std::string password) :
-        _user(std::move(user)), _password(std::move(password)) {}
+        Login(), _user(std::move(user)), _password(std::move(password)) {}
+
+    /**
+     *  Constructor for EXTERNAL mechanism
+     */
+    Login(LoginMechanism mechanism) : Login(), _mechanism(mechanism) {}
 
     /**
      *  Destructor
@@ -77,17 +97,38 @@ class Login
         return _password;
     }
 
+    /**
+     *  Retrieve login mechanism string representation
+     *  @return LoginMechanism
+     */
+    std::string mechanismRepr() const
+    {
+        switch (_mechanism)
+        {
+            case LOGIN_PLAIN:
+                return "PLAIN";
+            case LOGIN_EXTERNAL:
+                return "EXTERNAL";
+            default:
+                return "";
+        }
+    }
+
     /**
      *  String representation in SASL PLAIN mode
      *  @return string
      */
-    std::string saslPlain() const
+    std::string stringRepr() const
     {
         // we need an initial string
         std::string result("\0", 1);
 
-        // append other elements
-        return result.append(_user).append("\0",1).append(_password);
+        if (_mechanism == LOGIN_PLAIN) {
+            // append login and password info for plain login
+            return result.append(_user).append("\0",1).append(_password);
+        }
+
+        return result;
     }
 };
 
diff --git a/src/connectionstartframe.h b/src/connectionstartframe.h
index a8a08689..8d3c30c4 100644
--- a/src/connectionstartframe.h
+++ b/src/connectionstartframe.h
@@ -203,8 +203,9 @@ class ConnectionStartFrame : public ConnectionFrame
         // move connection to handshake mode
         connection->setProtocolOk();
         
-        // send back a connection start ok frame
-        connection->send(ConnectionStartOKFrame(properties, "PLAIN", connection->login().saslPlain(), "en_US"));
+        // send back a connection start ok frame with authentication data
+        connection->send(ConnectionStartOKFrame(properties, connection->login().mechanismRepr(),
+                                                connection->login().stringRepr(), "en_US"));
         
         // done
         return true;