diff --git a/detailed_docs/PutFile/CRC_Data_Integrity_Check/CRC_Data_Integrity_Check_TRS.md b/detailed_docs/PutFile/CRC_Data_Integrity_Check/CRC_Data_Integrity_Check_TRS.md
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+## Functional requirements
+
+1.   
+In case
+
+Mobile application sends a PutFile "Single Frame" with a known counted checksum to the SDL    
+
+SDL must  
+- receive PutFile "Single Frame"  
+- verify the counted checksum from the app (by comparing actual and received checksum) 
+- respond the app  with result code "SUCCESS"    
+
+2.   
+In case  
+
+Mobile application sends a PutFile "Single Frame" with a known wrong counted checksum to the SDL  
+
+SDL must  
+- receive PutFile "Single Frame"  
+- verify the counted checksum from the app 
+- respond with result code "CORRUPTED_DATA"  
+
+3.   
+In case  
+
+Mobile application sends a PutFile "Multiple Frame" with a known counted checksum to the SDL.  
+
+SDL must
+- receive PutFile "Multiple Frame" 
+- verify the counted checksum from the app
+- respond with result code "SUCCESS"
+
+4.  
+In case  
+
+Mobile application sends a PutFile "Multiple Frame" with a incorrect counted checksum to the SDL  
+
+SDL must  
+- receive PutFile "Multiple Frame"  
+- verify the counted checksum from the app   
+- respond with result code "CORRUPTED_DATA"
+
+5. 
+In case  
+
+Mobile application sends a PutFile without parameter `crc` to the SDL  
+
+SDL must
+- receive PutFile without parameter `crc`  
+- upload data  
+- respond with resultCode: "SUCCESS"
+
+6.   
+In case  
+
+Mobile application sends file via PutFile chunks  
+and SDL process some part of chunks with success result code  
+and one chunk came with wrong crc value and SDL responds with result code "CORRUPTED_DATA" to mobile app  
+
+SDL must  
+- response "CORRUPTED_DATA"  
+- process all other chunks with resultCode "INVALID_DATA"
+
+7.  
+In case  
+
+Mobile application sends a PutFile "Single Frame" with a negative (not valid) checksum to the SDL  
+
+SDL must  
+- SDL receive putfile "Single Frame" and counted checksum 
+- respond with result code "INVALID_DATA"
+
+8.  
+In case  
+
+Mobile application sends a PutFile "Multiple Frame" with a negative (not valid) checksum to the SDL  
+
+SDL must  
+- SDL receive putfile "Multiple Frame" and counted checksum  
+- respond with result code "INVALID_DATA"
+
+9.  
+In case  
+
+Mobile application sends a putfile "Single Frame" with a more than maxvalue (not valid) checksum to the SDL  
+
+SDL must  
+- receive putfile "Single Frame" and counted checksum 
+- respond with result code "INVALID_DATA" 
+
+10.  
+In case  
+
+Mobile application sends a putfile "Multiple Frame" with a more than maxvalue (not valid) checksum to the SDL  
+
+SDL must  
+- receive putfile "Multiple Frame" and counted checksum  
+- respond with result code "INVALID_DATA"
+
+
+11.  
+In case  
+
+Mobile application sends a PutFile with correct checksum  
+and some bytes of the data were corrupted  
+
+SDL must  
+- receive PutFile  
+- verify counted checksum  
+- respond with result code "CORRUPTED_DATA"  
+
+## Non-functional requirements  
+Addition to MOBILE API:
+```
+<enum name="Result" internal_scope="base">
+  <element name="CORRUPTED_DATA">
+    <description>The data sent failed to pass CRC check in receiver end</description>
+  </element>
+</enum>
+
+
+<function name="putFile" functionID="putFileID" messagetype="request">
+  [...]
+  <param name="crc" type="Integer" minvalue="0" maxvalue="4294967295" mandatory="false">
+    <description> Additional CRC32 checksum to protect data integrity up to 512 Mbits . </description>
+  </param>
+  [...]
+</function>
+
+
+<function name="putFile" functionID="putFileID" messagetype="response">
+  [...]
+  <param name="resultCode" type="Result" platform="documentation">
+      <description>See Result</description>
+      <element name=" CORRUPTED_DATA "/>
+  </param>
+  [...]
+</function>
+```
diff --git a/detailed_docs/PutFile/CRC_Data_Integrity_Check/CRC_Data_Integrity_Check_UC.md b/detailed_docs/PutFile/CRC_Data_Integrity_Check/CRC_Data_Integrity_Check_UC.md
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+## Use Case 1: Processing putFile request with CRC32 checksum
+
+_Pre-conditions:_
+a. SDL and HMI are started  
+b. Mobile application is successfully registered and running on SDL 
+
+_Steps:_  
+
+1. Mobile application sends a request to uploade a file as chunks to SDL  
+2. The request has known correct counted checksum  
+
+_Expected:_ 
+
+3. SDL verifies the counted checksum from the mobile application - valid 
+4. SDL responds with successful result code to mobile application  
+
+**Exception 1:**  
+
+2.1.1 The request has known wrong counted checksum 
+2.1.2 SDL responds with result code "CORRUPTED_DATA" to mobile application  
+
+**Exception 2:**  
+2.2.1 The request has negative (not valid) checksum  
+2.2.2 SDL responds with result code "INVALID_DATA" to mobile application  
+
+**Exception 3:**  
+2.3.1 The request has `value` more than `maxvalue`  
+2.3.2 SDL responds with result code "INVALID_DATA" to mobile application  
+
+**Exception 4:**  
+2.4.1 The request has no counted checksum  
+2.4.2 SDL uploads data and responds with successful result code to mobile application          
+
+**Alternative flow 1**  
+2.a.1 SDL processes some parts of chunks successfully and one chunk comes with wrong checksum value  
+2.a.2 SDL responds with result code "CORRUPTED_DATA" to mobile application  
+2.a.3 SDL responds with result code "INVALID_DATA" if mobile application sends further chanks 
+
+**Alternative flow 2** 
+2.b.1 The request has correct checksum and some bytes of the data were corrupted  
+2.b.2 SDL responds with result code "CORRUPTED_DATA" to mobile application   
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