Update README

README.md

@@ -73,6 +73,7 @@ Good mood
 - Output Feedback ([OFB](http://en.wikipedia.org/wiki/Block_cipher_mode_of_operation#Output_Feedback_.28OFB.29))
 - Counter Mode ([CTR](https://en.wikipedia.org/wiki/Block_cipher_mode_of_operation#Counter_.28CTR.29))
 - Galois/Counter Mode ([GCM](https://csrc.nist.gov/publications/detail/sp/800-38d/final))
+- Counter with Cipher Block Chaining-Message Authentication Code ([CCM](https://csrc.nist.gov/publications/detail/sp/800-38c/final))
 
 #### Password-Based Key Derivation Function
 - [PBKDF1](http://tools.ietf.org/html/rfc2898#section-5.1) (Password-Based Key Derivation Function 1)
@@ -450,7 +451,7 @@ decryption
 
 ```swift
 do {
-    // In combined mode, the authentication tag is directly appended to the encrypted message. This is usually what you want.
+    // In combined mode, the authentication tag is appended to the encrypted message. This is usually what you want.
     let gcm = GCM(iv: iv, mode: .combined)
     let aes = try AES(key: key, blockMode: gcm, padding: .noPadding)
     return try aes.decrypt(encrypted)
@@ -459,9 +460,26 @@ do {
 }
 ```
 
-
 **Note**: GCM instance is not intended to be reused. So you can't use the `GCM` from encoding, do decoding.
 
+##### AES-CCM
+
+The result of Counter with Cipher Block Chaining-Message Authentication Code encryption is ciphertext and **authentication tag**, that is later used to decryption.
+
+```
+do {
+    // The authentication tag is appended to the encrypted message.
+	let tagLength = 8
+	let ccm = CCM(iv: iv, tagLength: tagLength, messageLength: ciphertext.count - tagLength, additionalAuthenticatedData: data)
+    let aes = try AES(key: key, blockMode: ccm, padding: .noPadding)
+    return try aes.decrypt(encrypted)
+} catch {
+    // failed
+}
+```
+
+Check documentation or CCM specification for valid parameters for CCM.
+
 ##### AEAD
 
 ```swift