diff --git a/TL.php b/TL.php
index 420f295a..7f55c136 100644
--- a/TL.php
+++ b/TL.php
@@ -107,17 +107,17 @@ class TL
     {
         switch ($type_) {
             case 'int':
-                assert(is_numeric($value));
-                assert(strlen(decbin($value)) <= 32);
+                if(!is_numeric($value)) throw new Exception("serialize_param: given value isn't numeric");
+                if(!(strlen(decbin($value)) <= 32)) throw new Exception("Given value is too long.");
                 fwrite($bytes_io, $this->struct->pack('<i', $value));
                 break;
             case 'long':
-                assert(is_numeric($value));
+                if(!is_numeric($value)) throw new Exception("serialize_param: given value isn't numeric");
                 fwrite($bytes_io, $this->struct->pack('<q', $value));
                 break;
             case 'int128':
             case 'int256':
-                assert(is_string($value));
+                if(!is_string($value)) throw new Exception("serialize_param: given value isn't a string");
                 fwrite($bytes_io, $value);
                 break;
             case 'string':
@@ -144,7 +144,7 @@ class TL
      */
     public function deserialize($bytes_io, $type_ = null, $subtype = null)
     {
-        assert(get_resource_type($bytes_io) == 'file' || get_resource_type($bytes_io) == 'stream');
+        if(!(get_resource_type($bytes_io) == 'file' || get_resource_type($bytes_io) == 'stream')) throw new Exception("An invalid bytes_io handle provided.");
         switch ($type_) {
             case 'int':
                 $x = $this->struct->unpack('<i', fread($bytes_io, 4)) [0];
@@ -167,7 +167,7 @@ class TL
             case 'string':
             case 'bytes':
                 $l = $this->struct->unpack('<B', fread($bytes_io, 1)) [0];
-                assert($l <= 254);
+                if($l > 254) throw new Exception("Length is too big");;
                 if ($l == 254) {
                     $long_len = $this->struct->unpack('<I', fread($bytes_io, 3).string2bin('\x00')) [0];
                     $x = fread($bytes_io, $long_len);
@@ -176,10 +176,10 @@ class TL
                     $x = fread($bytes_io, $l);
                     fread($bytes_io, posmod(-($l + 1), 4));
                 }
-                assert(is_string($x));
+                if(!is_string($x)) throw new Exception("deserialize: generated value isn't a string");
                 break;
             case 'vector':
-                assert($subtype != null);
+                if($subtype == null) throw new Exception("deserialize: subtype isn't null");;
                 $count = $this->struct->unpack('<l', fread($bytes_io, 4)) [0];
                 $x = [];
                 foreach (pyjslib_range($count) as $i) {
diff --git a/mtproto.php b/mtproto.php
index e20e74b5..377656ac 100755
--- a/mtproto.php
+++ b/mtproto.php
@@ -1,5 +1,4 @@
 <?php
-
 set_include_path(get_include_path().PATH_SEPARATOR.dirname(__FILE__).DIRECTORY_SEPARATOR.'libpy2php');
 require_once 'libpy2php.php';
 require_once 'os_path.php';
@@ -196,8 +195,8 @@ class Session
             $encrypted_data = substr($packet, 28, -4 - 28);
             list($aes_key, $aes_iv) = $this->aes_calculate($message_key, 'from server');
             $decrypted_data = crypt::ige_decrypt($encrypted_data, $aes_key, $aes_iv);
-            assert((substr($decrypted_data, 0, 8 - 0) == $this->server_salt));
-            assert((substr($decrypted_data, 8, 16 - 8) == $this->session_id));
+            if (substr($decrypted_data, 0, 8) != $this->server_salt) throw new Exception("Server salt does not match.");
+            if (substr($decrypted_data, 8, 8) != $this->session_id) throw new Exception("Session id does not match.");
             $message_id = substr($decrypted_data, 16, 24 - 16);
             $seq_no = $this->struct->unpack('<I', substr($decrypted_data, 24, 28 - 24)) [0];
             $message_data_length = $this->struct->unpack('<I', substr($decrypted_data, 28, 32 - 28)) [0];
@@ -220,9 +219,13 @@ class Session
                 echo 'An error occurred while calling method '.$method.': '.$e->getMessage().PHP_EOL.'Stack trace:'.$e->getTraceAsString().PHP_EOL.'Retrying to call method...'.PHP_EOL.PHP_EOL;
                 continue;
             }
-
+            if ($server_answer == null) {
+                throw new Exception("An error occurred while calling method ".$method.'.');
+            }
             return $this->tl->deserialize(fopen_and_write('php://memory', 'rw+b', $server_answer));
         }
+        throw new Exception("An error occurred while calling method ".$method.'.');
+
     }
 
     public function create_auth_key()
@@ -230,6 +233,9 @@ class Session
         $nonce = \phpseclib\Crypt\Random::string(16);
         pyjslib_printnl('Requesting pq');
         $ResPQ = $this->method_call('req_pq', ['nonce' => $nonce]);
+        if ($ResPQ['nonce'] !== $nonce) {
+            throw new Exception("Handshake: wrong nonce");
+        }
         $server_nonce = $ResPQ['server_nonce'];
         $public_key_fingerprint = (int) $ResPQ['server_public_key_fingerprints'][0];
         $pq_bytes = $ResPQ['pq'];
@@ -241,23 +247,23 @@ class Session
         if ($p->compare($q) > 0) {
             list($p, $q) = [$q, $p];
         }
-        assert(($pq->equals($p->multiply($q))) && ($p < $q));
+        if(!(($pq->equals($p->multiply($q))) && ($p < $q))) throw new Exception("Handshake: couldn't compute p or q.");
         pyjslib_printnl(sprintf('Factorization %s = %s * %s', $pq, $p, $q));
-        $p_bytes = $this->struct->pack('>I', (string) $p);
-        $q_bytes = $this->struct->pack('>I', (string) $q);
+        $p_bytes = $this->struct->pack('>Q', (string) $p);
+        $q_bytes = $this->struct->pack('>Q', (string) $q);
         $f = file_get_contents(__DIR__.'/rsa.pub');
         $key = new \phpseclib\Crypt\RSA();
         $key->load($f);
         $new_nonce = \phpseclib\Crypt\Random::string(32);
         $data = $this->tl->serialize_obj('p_q_inner_data', ['pq' => $pq_bytes, 'p' => $p_bytes, 'q' => $q_bytes, 'nonce' => $nonce, 'server_nonce' => $server_nonce, 'new_nonce' => $new_nonce]);
         $sha_digest = sha1($data, true);
-        $random_bytes = \phpseclib\Crypt\Random::string(((255 - strlen($data)) - strlen($sha_digest)));
+        $random_bytes = \phpseclib\Crypt\Random::string(255 - strlen($data) - strlen($sha_digest));
         $to_encrypt = $sha_digest.$data.$random_bytes;
         $encrypted_data = $key->_raw_encrypt($to_encrypt);
         pyjslib_printnl('Starting Diffie Hellman key exchange');
         $server_dh_params = $this->method_call('req_DH_params', ['nonce' => $nonce, 'server_nonce' => $server_nonce, 'p' => $p_bytes, 'q' => $q_bytes, 'public_key_fingerprint' => $public_key_fingerprint, 'encrypted_data' => $encrypted_data]);
-        assert($nonce == $server_dh_params['nonce']);
-        assert($server_nonce == $server_dh_params['server_nonce']);
+        if($nonce != $server_dh_params['nonce']) throw new Exception("Handshake: wrong nonce.");
+        if($server_nonce != $server_dh_params['server_nonce']) throw new Exception("Handshake: wrong server nonce.");
         $encrypted_answer = $server_dh_params['encrypted_answer'];
         $tmp_aes_key = sha1($new_nonce.$server_nonce, true).substr(sha1($server_nonce.$new_nonce, true), 0, 12);
         $tmp_aes_iv = substr(sha1($server_nonce.$new_nonce, true), 12, 8).sha1($new_nonce.$new_nonce, true).substr($new_nonce, 0, 4);
@@ -265,8 +271,8 @@ class Session
         $answer_hash = substr($answer_with_hash, 0, 20);
         $answer = substr($answer_with_hash, 20);
         $server_DH_inner_data = deserialize(fopen_and_write('php://memory', 'rw+b', $answer));
-        assert($nonce == $server_DH_inner_data['nonce']);
-        assert($server_nonce == $server_DH_inner_data['server_nonce']);
+        if($nonce != $server_DH_inner_data['nonce']) throw new Exception("Handshake: wrong nonce");
+        if($server_nonce != $server_DH_inner_data['server_nonce']) throw new Exception("Handshake: wrong server nonce");;
         $dh_prime_str = $server_DH_inner_data['dh_prime'];
         $g = $server_DH_inner_data['g'];
         $g_a_str = $server_DH_inner_data['g_a'];
@@ -275,7 +281,7 @@ class Session
         pyjslib_printnl(sprintf('Server-client time delta = %.1f s', $this->timedelta));
         $dh_prime = $this->struct->unpack('>Q', $dh_prime_str);
         $g_a = $this->struct->unpack('>Q', $g_a_str);
-        assert($this->PrimeModule->isprime($dh_prime));
+        if(!$this->PrimeModule->isprime($dh_prime)) throw new Exception("Handshake: dh_prime isn't a prime.");;
         $retry_id = 0;
         $b_str = \phpseclib\Crypt\Random::string(256);
         $b = $this->struct->unpack('>Q', $b_str);
@@ -294,10 +300,10 @@ class Session
             $new_nonce_hash1 = substr(sha1($new_nonce.'
'.$auth_key_aux_hash, true), -16);
             $new_nonce_hash2 = substr(sha1($new_nonce.''.$auth_key_aux_hash, true), -16);
             $new_nonce_hash3 = substr(sha1($new_nonce.''.$auth_key_aux_hash, true), -16);
-            assert($Set_client_DH_params_answer['nonce'] == $nonce);
-            assert($Set_client_DH_params_answer['server_nonce'] == $server_nonce);
+            if($Set_client_DH_params_answer['nonce'] != $nonce) throw new Exception("Handshake: wrong nonce.");
+            if($Set_client_DH_params_answer['server_nonce'] != $server_nonce) throw new Exception("Handshake: wrong server nonce");;
             if ($Set_client_DH_params_answer->name == 'dh_gen_ok') {
-                assert($Set_client_DH_params_answer['new_nonce_hash1'] == $new_nonce_hash1);
+                if($Set_client_DH_params_answer['new_nonce_hash1'] != $new_nonce_hash1) throw new Exception("Handshake: wrong new_nonce_hash1");;
                 pyjslib_printnl('Diffie Hellman key exchange processed successfully');
                 $this->server_salt = new strxor(substr($new_nonce, 0, 8 - 0), substr($server_nonce, 0, 8 - 0));
                 $this->auth_key = $auth_key_str;
@@ -305,11 +311,11 @@ class Session
                 pyjslib_printnl('Auth key generated');
 
                 return 'Auth Ok';
-            } elseif (($Set_client_DH_params_answer->name == 'dh_gen_retry')) {
-                assert($Set_client_DH_params_answer['new_nonce_hash2'] == $new_nonce_hash2);
+            } elseif ($Set_client_DH_params_answer->name == 'dh_gen_retry') {
+                if($Set_client_DH_params_answer['new_nonce_hash2'] != $new_nonce_hash2) throw new Exception("Handshake: wrong new_nonce_hash_2");
                 pyjslib_printnl('Retry Auth');
-            } elseif (($Set_client_DH_params_answer->name == 'dh_gen_fail')) {
-                assert($Set_client_DH_params_answer['new_nonce_hash3'] == $new_nonce_hash3);
+            } elseif ($Set_client_DH_params_answer->name == 'dh_gen_fail') {
+                if($Set_client_DH_params_answer['new_nonce_hash3'] != $new_nonce_hash3) throw new Exception("Handshake: wrong new_nonce_hash_3");
                 pyjslib_printnl('Auth Failed');
                 throw new Exception('Auth Failed');
             } else {