diff --git a/Modules/CppRestSdk/include/mitkIRESTManager.h b/Modules/CppRestSdk/include/mitkIRESTManager.h
index 288ee47c12..c1eb34d68b 100644
--- a/Modules/CppRestSdk/include/mitkIRESTManager.h
+++ b/Modules/CppRestSdk/include/mitkIRESTManager.h
@@ -1,31 +1,29 @@
 #ifndef mitkIRESTManager_h
 #define mitkIRESTManager_h
 
+#include "cpprest/uri.h"
 #include <MitkCoreExports.h>
 #include <mitkServiceInterface.h>
-#include "cpprest/uri.h"
+#include <mitkIRESTObserver.h>
 
 namespace mitk
 {
   class IRESTManager
   {
   public:
     virtual ~IRESTManager();
 
     enum RequestType
     {
       get,
       post,
       put
     };
     virtual void sendRequest(RequestType type) = 0;
-    virtual void receiveRequest(web::uri uri) = 0;
-
-
-
+    virtual void receiveRequest(web::uri uri, IRESTObserver *observer) = 0;
   };
 } // namespace mitk
 
 MITK_DECLARE_SERVICE_INTERFACE(mitk::IRESTManager, "org.mitk.IRESTManager")
 
 #endif
diff --git a/Modules/CppRestSdk/include/mitkRESTManager.h b/Modules/CppRestSdk/include/mitkRESTManager.h
index 02b0ec317e..9964edbd4b 100644
--- a/Modules/CppRestSdk/include/mitkRESTManager.h
+++ b/Modules/CppRestSdk/include/mitkRESTManager.h
@@ -1,26 +1,28 @@
 #ifndef mitkRESTManager_h
 #define mitkRESTManager_h
 
 #include <mitkIRESTManager.h>
 #include <mitkRESTClientMicroService.h>
 #include <mitkRESTServerMicroService.h>
+#include <mitkIRESTObserver.h>
 
 namespace mitk
 {
   class RESTManager : public IRESTManager
   {
   public:
     RESTManager();
     ~RESTManager() override;
 
     //calls RESTClient
     void sendRequest(RequestType type) override;
     //calls RESTServer
-    void receiveRequest(web::uri uri) override;
+    void receiveRequest(web::uri uri, IRESTObserver *observer) override;
 
   private:
     std::map<int, RESTClientMicroService*> m_ClientMap; // Map with port client pairs
     std::map<int, RESTServerMicroService*> m_ServerMap; // Map with port server pairs
+    std::map<web::uri, IRESTObserver *> m_Observer; //Map with all observers
   };
 } // namespace mitk
 #endif // !mitkRESTManager_h
diff --git a/Modules/CppRestSdk/src/mitkRESTManager.cpp b/Modules/CppRestSdk/src/mitkRESTManager.cpp
index 10d74f3d42..9f038b7c16 100644
--- a/Modules/CppRestSdk/src/mitkRESTManager.cpp
+++ b/Modules/CppRestSdk/src/mitkRESTManager.cpp
@@ -1,50 +1,69 @@
 #include "mitkRESTManager.h"
 #include <mitkCommon.h>
 
 mitk::RESTManager::RESTManager() {}
 
 mitk::RESTManager::~RESTManager() {}
 
 void mitk::RESTManager::sendRequest(RequestType type) 
 {
   switch (type)
   {
     case get:
       //Call get in mitkRESTClientMicroService
       break;
     case post:
       //Call post in mitkRESTClientMicroService
       break;
     case put:
       //Call put in mitkRESTClientMicroService
       break;
   }
 }
 
-void mitk::RESTManager::receiveRequest(web::uri uri) 
+void mitk::RESTManager::receiveRequest(web::uri uri, mitk::IRESTObserver *observer)
 {
   //New instance of RESTServerMicroservice in m_ServerMap, key is port of the request
   int port = uri.port();
   
   if (m_ServerMap.count(port) == 0)
   {
     //new observer has to be added
+    m_Observer[uri] = observer;
+
+    //testing if entry has been added to map
+    utility::string_t uristringt = uri.to_string();
+    std::string uristring(uristringt.begin(), uristringt.end());
+    MITK_INFO << uristring << " : Number of elements in map: " << m_Observer.count(uri);
+
+    //creating server instance
     RESTServerMicroService *server = new RESTServerMicroService(uri.authority());
+    //add reference to server instance to map
     m_ServerMap[port] = server;
+
+    //info output
     utility::string_t host = uri.authority().to_string();
     std::string hoststring(host.begin(), host.end());
     MITK_INFO << "new server" << hoststring<<" at port" << port;
   }
   else
   {
     if (m_ServerMap[port]->GetUri() == uri.authority())
     {
       //new observer has to be added
-      MITK_INFO << "started listening";
+      m_Observer[uri] = observer;
+
+      // testing if entry has been added to map
+      utility::string_t uristringt = uri.to_string();
+      std::string uristring(uristringt.begin(), uristringt.end());
+      MITK_INFO << uristring << " : Number of elements in map: " << m_Observer.count(uri);
+
+      //info output
+      MITK_INFO << "started listening, no new server instance has been created";
     }
     else
     {
       MITK_ERROR << "there is already another server listening under this port";
     }
   }
 }
diff --git a/Modules/CppRestSdk/src/mitkRESTTest.cpp b/Modules/CppRestSdk/src/mitkRESTTest.cpp
index b975b2fde2..c74c73bd4e 100644
--- a/Modules/CppRestSdk/src/mitkRESTTest.cpp
+++ b/Modules/CppRestSdk/src/mitkRESTTest.cpp
@@ -1,29 +1,29 @@
 #include "mitkRESTTest.h"
 #include <usGetModuleContext.h>
 #include <usModule.h>
 #include <mitkCommon.h>
 
 mitk::RestTest::RestTest() {}
 
 mitk::RestTest::~RestTest() {}
 
 void mitk::RestTest::TestRESTServer()
 {
   us::ModuleContext *context = us::GetModuleContext();
   auto managerRef = context->GetServiceReference<IRESTManager>();
   if (managerRef)
   {
     auto managerService = context->GetService(managerRef);
     if (managerService)
     {
-      managerService->receiveRequest(L"http://localhost:8080/test");
-      managerService->receiveRequest(L"http://localhost:8080/example");
-      managerService->receiveRequest(L"http://localhost:8090");
+      managerService->receiveRequest(L"http://localhost:8080/test", this);
+      managerService->receiveRequest(L"http://localhost:8080/example", this);
+      managerService->receiveRequest(L"http://localhost:8090", this);
     }
   }
 }
 
 bool mitk::RestTest::notify() 
 {
   return true;
 }