diff --git a/README.md b/README.md
index 41c9c368..ab975f57 100644
--- a/README.md
+++ b/README.md
@@ -9,7 +9,7 @@ Add `plivo/plivo-php` as a dependency in your project's `composer.json` file:
 ```json
 {
 	"require": {
-		"plivo/plivo-php": "v1.0.2"
+		"plivo/plivo-php": "v1.1.1"
 	}
 }
 ```
diff --git a/plivo.php b/plivo.php
index f3354bfb..6b1d91da 100644
--- a/plivo.php
+++ b/plivo.php
@@ -26,6 +26,15 @@ function __construct($auth_id, $auth_token, $url = "https://api.plivo.com", $ver
         $this->auth_token = $auth_token;
     }
 
+    public static function validate_signature($uri, $post_params=array(), $signature, $auth_token) {
+        ksort($post_params);
+        foreach($post_params as $key => $value) {
+            $uri .= "$key$value";
+        }
+        $generated_signature = base64_encode(hash_hmac("sha1",$uri, $auth_token, true));
+        return $generated_signature == $signature;
+    }
+
     private function request($method, $path, $params = array()) {
         $url = $this->api.rtrim($path, '/').'/';