diff --git a/src/Requests/Header.php b/src/Requests/Header.php
new file mode 100644
index 0000000..8a4201b
--- /dev/null
+++ b/src/Requests/Header.php
@@ -0,0 +1,50 @@
+<?php
+
+namespace Msr\LaravelBitunixApi\Requests;
+
+class Header
+{
+    public static function sortQueryParameters(array $parameters): ?array
+    {
+        $sortableParameters = $parameters;
+
+        if (!count($sortableParameters)) {
+            return [];
+        }
+
+        ksort($sortableParameters, SORT_LOCALE_STRING);
+        return $sortableParameters;
+    }
+
+    public static function digestQueryParameters(array $parameters): ?string
+    {
+        if (!count($parameters)) {
+            return null;
+        }
+
+        $sortedParameters = self::sortQueryParameters($parameters);
+        return implode('', array_map(
+            fn($k, $v) => $k . $v,
+            array_keys($sortedParameters),
+            array_values($sortedParameters)
+        ));
+    }
+
+    public static function generateNonce(): ?string
+    {
+        return md5(uniqid(mt_rand(), true));
+    }
+
+    public static function generateSignValue(array $queryParams = [], string $body = '', string $randomNonce = ''): string
+    {
+        $apiKey = config('bitunix-api.api_key');
+        $apiSecret = config('bitunix-api.api_secret');
+        $timeStamp = (string)round(microtime(true) * 1000);
+        $digestedQueryParam = self::digestQueryParameters($queryParams);
+
+        $digestedHeader = $randomNonce . $timeStamp . $apiKey . $digestedQueryParam . $body;
+        $hash = hash('sha256', $digestedHeader);
+        $sign = $hash . $apiSecret;
+        return hash('sha256', $sign);
+    }
+}
diff --git a/tests/AuthHeaderTest.php b/tests/AuthHeaderTest.php
new file mode 100644
index 0000000..3f39327
--- /dev/null
+++ b/tests/AuthHeaderTest.php
@@ -0,0 +1,48 @@
+<?php
+
+use Msr\LaravelBitunixApi\Requests\Header;
+
+it('sort query parameters', function () {
+
+    $emptyQuery = Header::sortQueryParameters([]);
+    expect($emptyQuery)->toBeEmpty();
+
+    $params = [
+        'z_index' => 'z value',
+        'a_index' => 'a value',
+        'b_index' => 'b value',
+    ];
+    $sortedParams = Header::sortQueryParameters($params);
+    expect($sortedParams)
+        ->toMatchArray([
+            'a_index' => 'a value',
+            'b_index' => 'b value',
+            'z_index' => 'z value',
+        ]);
+});
+
+it('get sorted query params as string value', function () {
+
+    $digestedParam = Header::digestQueryParameters([]);
+    expect($digestedParam)->toBeNull();
+
+    $params = [
+        'z_index' => 'z_value',
+        'a_index' => 'a_value',
+        'b_index' => 'b_value',
+    ];
+    $sortedParams = Header::digestQueryParameters($params);
+    expect($sortedParams)->toEqual('a_indexa_valueb_indexb_valuez_indexz_value');
+});
+
+it('get some random string 32 bit', function () {
+
+    $firstRandom = Header::generateNonce();
+    $secondRandom = Header::generateNonce();
+
+    expect($firstRandom)
+        ->toBeString()
+        ->toHaveLength(32)
+        ->not()->toEqual($secondRandom)
+        ->not()->toBeNull();
+});
diff --git a/tests/ExampleTest.php b/tests/ExampleTest.php
deleted file mode 100644
index 5d36321..0000000
--- a/tests/ExampleTest.php
+++ /dev/null
@@ -1,5 +0,0 @@
-<?php
-
-it('can test', function () {
-    expect(true)->toBeTrue();
-});