diff --git a/include/protocol/protocol.hpp b/include/protocol/protocol.hpp
index 359ab40..c92f957 100644
--- a/include/protocol/protocol.hpp
+++ b/include/protocol/protocol.hpp
@@ -35,6 +35,10 @@ namespace protocol {
         void absorb(const std::string& input);
         void send(const token::list_t& tokens);
 
+        void send_result(const session_key_t& session_key, token::list_t tokens);
+        void proceed(const session_key_t& session_key);
+        void fail(const session_key_t& session_key);
+
         void submit_message(const session_key_t& session_key, const std::vector<std::string>& header, const std::vector<std::string>& body);
 
     protected:
diff --git a/src/protocol/protocol.cpp b/src/protocol/protocol.cpp
index 00e593a..bd74168 100644
--- a/src/protocol/protocol.cpp
+++ b/src/protocol/protocol.cpp
@@ -37,16 +37,34 @@ namespace protocol {
     void protocol_t::absorb(const std::string& input) {
         auto tokens = token::decompose(input, max_pattern_length);
         auto pattern = token::pattern_t(tokens, false);
-        debug && cout << "Received pattern " << pattern << endl;
+        debug && cerr << "Received pattern " << pattern << endl;
 
         auto element = handlers.find(pattern);
-        if(element != handlers.end()) {
+        if(element == handlers.end()) {
+            debug && cerr << "Unknown pattern " << pattern << endl;
+        } else {
             element->second(*this, {input, element->first});
         }
     }
 
+    void protocol_t::send_result(const session_key_t& session_key, token::list_t tokens) {
+        token::list_t result{"filter-result", session_key.session, session_key.token};
+        for(auto& token : tokens) {
+            result.push_back(token);
+        }
+        send(result);
+    }
+
+    void protocol_t::proceed(const session_key_t& session_key) {
+        send_result(session_key, {"proceed"});
+    }
+
+    void protocol_t::fail(const session_key_t& session_key) {
+        send_result(session_key, {"disconnect", "451 Aborted"});
+    }
+
     void protocol_t::send_data_line(const session_key_t& session_key, const string& data_line) {
-        send({"filter-dataline", session_key.session, session_key.token, session_key.token, data_line});
+        send({"filter-dataline", session_key.session, session_key.token, data_line});
     }
 
     void protocol_t::submit_message(const session_key_t& session_key, const vector<string>& header, const vector<string>& body) {