diff --git a/taoyao-client-media/src/Config.js b/taoyao-client-media/src/Config.js
index e8c9389..b1d632c 100644
--- a/taoyao-client-media/src/Config.js
+++ b/taoyao-client-media/src/Config.js
@@ -65,8 +65,9 @@ module.exports = {
       ],
       // 日志级别：debug | warn | error | none
       logLevel  : "warn",
-      // RTP端口范围
+      // RTP端口范围（最小）
       rtcMinPort: process.env.MEDIASOUP_MIN_PORT || 40000,
+      // RTP端口范围（最大）
       rtcMaxPort: process.env.MEDIASOUP_MAX_PORT || 49999,
     },
     // Router配置：https://mediasoup.org/documentation/v3/mediasoup/api/#RouterOptions
diff --git a/taoyao-signal-server/taoyao-signal/src/main/java/com/acgist/taoyao/signal/utils/CipherUtils.java b/taoyao-signal-server/taoyao-signal/src/main/java/com/acgist/taoyao/signal/utils/CipherUtils.java
index 9339552..927a048 100644
--- a/taoyao-signal-server/taoyao-signal/src/main/java/com/acgist/taoyao/signal/utils/CipherUtils.java
+++ b/taoyao-signal-server/taoyao-signal/src/main/java/com/acgist/taoyao/signal/utils/CipherUtils.java
@@ -20,12 +20,14 @@ import lombok.extern.slf4j.Slf4j;
  * @author acgist
  */
 @Slf4j
-public class CipherUtils {
+public final class CipherUtils {
 
     private CipherUtils() {
     }
     
     /**
+     * 创建加密工具
+     * 
      * @param mode    模式
      * @param encrypt 算法
      * @param secret  密钥
diff --git a/taoyao-signal-server/taoyao-signal/src/test/java/com/acgist/taoyao/signal/utils/CipherUtilsTest.java b/taoyao-signal-server/taoyao-signal/src/test/java/com/acgist/taoyao/signal/utils/CipherUtilsTest.java
new file mode 100644
index 0000000..3a1a80a
--- /dev/null
+++ b/taoyao-signal-server/taoyao-signal/src/test/java/com/acgist/taoyao/signal/utils/CipherUtilsTest.java
@@ -0,0 +1,22 @@
+package com.acgist.taoyao.signal.utils;
+
+import static org.junit.jupiter.api.Assertions.assertNotNull;
+import static org.junit.jupiter.api.Assertions.assertNull;
+
+import javax.crypto.Cipher;
+
+import org.junit.jupiter.api.Test;
+
+import com.acgist.taoyao.boot.config.SocketProperties.Encrypt;
+
+public class CipherUtilsTest {
+    
+    @Test
+    public void testBuildCipher() {
+        final String secret = "2SPWy+TF1zM=".strip();
+        assertNull(CipherUtils.buildCipher(Cipher.ENCRYPT_MODE, Encrypt.PLAINTEXT, secret));
+        assertNull(CipherUtils.buildCipher(Cipher.ENCRYPT_MODE, Encrypt.DES, null));
+        assertNotNull(CipherUtils.buildCipher(Cipher.ENCRYPT_MODE, Encrypt.DES, secret));
+    }
+
+}