diff --git a/phpseclib/Net/SSH2.php b/phpseclib/Net/SSH2.php
index ec7ed63a..b298df1e 100644
--- a/phpseclib/Net/SSH2.php
+++ b/phpseclib/Net/SSH2.php
@@ -52,45 +52,6 @@ use \phpseclib\Crypt\Random;
 // Used to do Diffie-Hellman key exchange and DSA/RSA signature verification.
 use \phpseclib\Math\BigInteger;
 
-/**#@+
- * Execution Bitmap Masks
- *
- * @see Net_SSH2::bitmap
- * @access private
- */
-define('NET_SSH2_MASK_CONSTRUCTOR',   0x00000001);
-define('NET_SSH2_MASK_CONNECTED',     0x00000002);
-define('NET_SSH2_MASK_LOGIN_REQ',     0x00000004);
-define('NET_SSH2_MASK_LOGIN',         0x00000008);
-define('NET_SSH2_MASK_SHELL',         0x00000010);
-define('NET_SSH2_MASK_WINDOW_ADJUST', 0x00000020);
-/**#@-*/
-
-/**#@+
- * Channel constants
- *
- * RFC4254 refers not to client and server channels but rather to sender and recipient channels.  we don't refer
- * to them in that way because RFC4254 toggles the meaning. the client sends a SSH_MSG_CHANNEL_OPEN message with
- * a sender channel and the server sends a SSH_MSG_CHANNEL_OPEN_CONFIRMATION in response, with a sender and a
- * recepient channel.  at first glance, you might conclude that SSH_MSG_CHANNEL_OPEN_CONFIRMATION's sender channel
- * would be the same thing as SSH_MSG_CHANNEL_OPEN's sender channel, but it's not, per this snipet:
- *     The 'recipient channel' is the channel number given in the original
- *     open request, and 'sender channel' is the channel number allocated by
- *     the other side.
- *
- * @see Net_SSH2::_send_channel_packet()
- * @see Net_SSH2::_get_channel_packet()
- * @access private
- */
-define('NET_SSH2_CHANNEL_EXEC',      0); // PuTTy uses 0x100
-define('NET_SSH2_CHANNEL_SHELL',     1);
-define('NET_SSH2_CHANNEL_SUBSYSTEM', 2);
-/**#@-*/
-
-/**#@+
- * @access public
- * @see Net_SSH2::getLog()
- */
 /**
  * Pure-PHP implementation of SSHv2.
  *
@@ -1896,10 +1857,10 @@ class Net_SSH2
 
         // although PHP5's get_class() preserves the case, PHP4's does not
         if (is_object($password)) {
-            switch (strtolower(get_class($password))) {
-                case 'crypt_rsa':
+            switch (get_class($password)) {
+                case 'Crypt_RSA':
                     return $this->_privatekey_login($username, $password);
-                case 'system_ssh_agent':
+                case 'phpseclib\System\SSH\Agent':
                     return $this->_ssh_agent_login($username, $password);
             }
         }
@@ -2141,7 +2102,7 @@ class Net_SSH2
      * Login with an ssh-agent provided key
      *
      * @param String $username
-     * @param System_SSH_Agent $agent
+     * @param \phpseclib\System\SSH\Agent $agent
      * @return Boolean
      * @access private
      */
diff --git a/phpseclib/System/SSH/Agent.php b/phpseclib/System/SSH/Agent.php
index 6739d5a4..c4c79918 100644
--- a/phpseclib/System/SSH/Agent.php
+++ b/phpseclib/System/SSH/Agent.php
@@ -10,7 +10,7 @@
  *    include 'System/SSH/Agent.php';
  *    include 'Net/SSH2.php';
  *
- *    $agent = new System_SSH_Agent();
+ *    $agent = new \phpseclib\System\SSH\Agent();
  *
  *    $ssh = new Net_SSH2('www.domain.tld');
  *    if (!$ssh->login('username', $agent)) {
@@ -23,7 +23,7 @@
  * </code>
  *
  * @category  System
- * @package   System_SSH_Agent
+ * @package   SSH\Agent
  * @author    Jim Wigginton <terrafrost@php.net>
  * @copyright 2014 Jim Wigginton
  * @license   http://www.opensource.org/licenses/mit-license.html  MIT License
@@ -31,20 +31,21 @@
  * @internal  See http://api.libssh.org/rfc/PROTOCOL.agent
  */
 
-if (!class_exists('System_SSH_Agent_Identity')) {
-    include_once 'Agent/Identity.php';
-}
+namespace phpseclib\System\SSH;
+
+use Crypt_RSA; //This should be removed once the Crypt package is fully namespaced
+use phpseclib\System\SSH\Agent\Identity;
 
 /**
  * Pure-PHP ssh-agent client identity factory
  *
- * requestIdentities() method pumps out System_SSH_Agent_Identity objects
+ * requestIdentities() method pumps out \phpseclib\System\SSH\Agent\Identity objects
  *
- * @package System_SSH_Agent
+ * @package SSH\Agent
  * @author  Jim Wigginton <terrafrost@php.net>
  * @access  internal
  */
-class System_SSH_Agent
+class Agent
 {
     /**#@+
      * Message numbers
@@ -77,7 +78,7 @@ class System_SSH_Agent
     /**
      * Default Constructor
      *
-     * @return System_SSH_Agent
+     * @return \phpseclib\System\SSH\Agent
      * @access public
      */
     function __construct()
@@ -104,7 +105,7 @@ class System_SSH_Agent
      * Request Identities
      *
      * See "2.5.2 Requesting a list of protocol 2 keys"
-     * Returns an array containing zero or more System_SSH_Agent_Identity objects
+     * Returns an array containing zero or more \phpseclib\System\SSH\Agent\Identity objects
      *
      * @return Array
      * @access public
@@ -149,7 +150,7 @@ class System_SSH_Agent
             }
             // resources are passed by reference by default
             if (isset($key)) {
-                $identity = new System_SSH_Agent_Identity($this->fsock);
+                $identity = new Identity($this->fsock);
                 $identity->setPublicKey($key);
                 $identity->setPublicKeyBlob($key_blob);
                 $identities[] = $identity;
diff --git a/phpseclib/System/SSH/Agent/Identity.php b/phpseclib/System/SSH/Agent/Identity.php
index c5f92983..0cc768dd 100644
--- a/phpseclib/System/SSH/Agent/Identity.php
+++ b/phpseclib/System/SSH/Agent/Identity.php
@@ -5,7 +5,7 @@
  * PHP versions 4 and 5
  *
  * @category  System
- * @package   System_SSH_Agent
+ * @package   SSH\Agent
  * @author    Jim Wigginton <terrafrost@php.net>
  * @copyright 2009 Jim Wigginton
  * @license   http://www.opensource.org/licenses/mit-license.html  MIT License
@@ -13,28 +13,32 @@
  * @internal  See http://api.libssh.org/rfc/PROTOCOL.agent
  */
 
+namespace phpseclib\System\SSH\Agent;
+
+use phpseclib\System\SSH\Agent;
+
 /**
  * Pure-PHP ssh-agent client identity object
  *
- * Instantiation should only be performed by System_SSH_Agent class.
+ * Instantiation should only be performed by \phpseclib\System\SSH\Agent class.
  * This could be thought of as implementing an interface that Crypt_RSA
  * implements. ie. maybe a Net_SSH_Auth_PublicKey interface or something.
  * The methods in this interface would be getPublicKey, setSignatureMode
  * and sign since those are the methods phpseclib looks for to perform
  * public key authentication.
  *
- * @package System_SSH_Agent
+ * @package SSH\Agent
  * @author  Jim Wigginton <terrafrost@php.net>
  * @access  internal
  */
-class System_SSH_Agent_Identity
+class Identity
 {
     /**
      * Key Object
      *
      * @var Crypt_RSA
      * @access private
-     * @see System_SSH_Agent_Identity::getPublicKey()
+     * @see \phpseclib\System\SSH\Agent\Identity::getPublicKey()
      */
     var $key;
 
@@ -43,7 +47,7 @@ class System_SSH_Agent_Identity
      *
      * @var String
      * @access private
-     * @see System_SSH_Agent_Identity::sign()
+     * @see \phpseclib\System\SSH\Agent\Identity::sign()
      */
     var $key_blob;
 
@@ -52,7 +56,7 @@ class System_SSH_Agent_Identity
      *
      * @var Resource
      * @access private
-     * @see System_SSH_Agent_Identity::sign()
+     * @see \phpseclib\System\SSH\Agent\Identity::sign()
      */
     var $fsock;
 
@@ -60,7 +64,7 @@ class System_SSH_Agent_Identity
      * Default Constructor.
      *
      * @param Resource $fsock
-     * @return System_SSH_Agent_Identity
+     * @return \phpseclib\System\SSH\Agent\Identity
      * @access private
      */
     function __construct($fsock)
@@ -71,7 +75,7 @@ class System_SSH_Agent_Identity
     /**
      * Set Public Key
      *
-     * Called by System_SSH_Agent::requestIdentities()
+     * Called by \phpseclib\System\SSH\Agent::requestIdentities()
      *
      * @param Crypt_RSA $key
      * @access private
@@ -85,7 +89,7 @@ class System_SSH_Agent_Identity
     /**
      * Set Public Key
      *
-     * Called by System_SSH_Agent::requestIdentities(). The key blob could be extracted from $this->key
+     * Called by \phpseclib\System\SSH\Agent::requestIdentities(). The key blob could be extracted from $this->key
      * but this saves a small amount of computation.
      *
      * @param String $key_blob
@@ -135,7 +139,7 @@ class System_SSH_Agent_Identity
     function sign($message)
     {
         // the last parameter (currently 0) is for flags and ssh-agent only defines one flag (for ssh-dss): SSH_AGENT_OLD_SIGNATURE
-        $packet = pack('CNa*Na*N', System_SSH_Agent::SSH_AGENTC_SIGN_REQUEST, strlen($this->key_blob), $this->key_blob, strlen($message), $message, 0);
+        $packet = pack('CNa*Na*N', Agent::SSH_AGENTC_SIGN_REQUEST, strlen($this->key_blob), $this->key_blob, strlen($message), $message, 0);
         $packet = pack('Na*', strlen($packet), $packet);
         if (strlen($packet) != fputs($this->fsock, $packet)) {
             user_error('Connection closed during signing');
@@ -143,7 +147,7 @@ class System_SSH_Agent_Identity
 
         $length = current(unpack('N', fread($this->fsock, 4)));
         $type = ord(fread($this->fsock, 1));
-        if ($type != System_SSH_Agent::SSH_AGENT_SIGN_RESPONSE) {
+        if ($type != Agent::SSH_AGENT_SIGN_RESPONSE) {
             user_error('Unable to retreive signature');
         }
 
diff --git a/tests/Functional/Net/SSH2AgentTest.php b/tests/Functional/Net/SSH2AgentTest.php
index d92bb705..e8dc4403 100644
--- a/tests/Functional/Net/SSH2AgentTest.php
+++ b/tests/Functional/Net/SSH2AgentTest.php
@@ -6,6 +6,8 @@
  * @license   http://www.opensource.org/licenses/mit-license.html  MIT License
  */
 
+use phpseclib\System\SSH\Agent;
+
 class Functional_Net_SSH2AgentTest extends PhpseclibFunctionalTestCase
 {
     public static function setUpBeforeClass()
@@ -21,7 +23,7 @@ class Functional_Net_SSH2AgentTest extends PhpseclibFunctionalTestCase
     public function testAgentLogin()
     {
         $ssh = new Net_SSH2($this->getEnv('SSH_HOSTNAME'));
-        $agent = new System_SSH_Agent;
+        $agent = new Agent;
 
         $this->assertTrue(
             $ssh->login($this->getEnv('SSH_USERNAME'), $agent),