diff --git a/.gitignore b/.gitignore
index cdd81d5d..a21f71d9 100644
--- a/.gitignore
+++ b/.gitignore
@@ -66,5 +66,7 @@ compile_commands.json
 notes.txt
 sanitizer-suppressions.txt
 snapserver.conf
+certs
+server/etc/certs
 
 extras/package/debian/snap*.debhelper.log
diff --git a/client/client_connection.cpp b/client/client_connection.cpp
index db160c3e..603c3d43 100644
--- a/client/client_connection.cpp
+++ b/client/client_connection.cpp
@@ -29,6 +29,7 @@
 #include <boost/asio/write.hpp>
 
 // standard headers
+#include <cstdint>
 #include <iostream>
 
 
@@ -91,8 +92,8 @@ bool PendingRequest::operator<(const PendingRequest& other) const
 
 
 
-ClientConnection::ClientConnection(boost::asio::io_context& io_context, const ClientSettings::Server& server)
-    : strand_(boost::asio::make_strand(io_context.get_executor())), resolver_(strand_), socket_(strand_), reqId_(1), server_(server)
+ClientConnection::ClientConnection(boost::asio::io_context& io_context, ClientSettings::Server server)
+    : strand_(boost::asio::make_strand(io_context.get_executor())), resolver_(strand_), socket_(strand_), reqId_(1), server_(std::move(server))
 {
     base_msg_size_ = base_message_.getSize();
     buffer_.resize(base_msg_size_);
@@ -247,10 +248,11 @@ void ClientConnection::sendRequest(const msg::message_ptr& message, const chrono
     boost::asio::post(strand_, [this, message, timeout, handler]()
     {
         pendingRequests_.erase(
-            std::remove_if(pendingRequests_.begin(), pendingRequests_.end(), [](std::weak_ptr<PendingRequest> request) { return request.expired(); }),
+            std::remove_if(pendingRequests_.begin(), pendingRequests_.end(), [](const std::weak_ptr<PendingRequest>& request) { return request.expired(); }),
             pendingRequests_.end());
         unique_ptr<msg::BaseMessage> response(nullptr);
-        if (++reqId_ >= 10000)
+        static constexpr uint16_t max_req_id = 10000;
+        if (++reqId_ >= max_req_id)
             reqId_ = 1;
         message->id = reqId_;
         auto request = make_shared<PendingRequest>(strand_, reqId_, handler);
diff --git a/client/client_connection.hpp b/client/client_connection.hpp
index 62843888..5298637e 100644
--- a/client/client_connection.hpp
+++ b/client/client_connection.hpp
@@ -83,10 +83,11 @@ private:
 class ClientConnection
 {
 public:
+    /// Result callback with boost::error_code
     using ResultHandler = std::function<void(const boost::system::error_code&)>;
 
     /// c'tor
-    ClientConnection(boost::asio::io_context& io_context, const ClientSettings::Server& server);
+    ClientConnection(boost::asio::io_context& io_context, ClientSettings::Server server);
     /// d'tor
     virtual ~ClientConnection();
 
@@ -122,6 +123,7 @@ public:
         });
     }
 
+    /// @return MAC address of the client
     std::string getMacAddress();
 
     /// async get the next message
@@ -129,26 +131,42 @@ public:
     void getNextMessage(const MessageHandler<msg::BaseMessage>& handler);
 
 protected:
+    /// Send next pending message from messages_
     void sendNext();
 
+    /// Base message holding the received message
     msg::BaseMessage base_message_;
+    /// Receive buffer
     std::vector<char> buffer_;
+    /// Size of a base message (= message header)
     size_t base_msg_size_;
 
+    /// Strand to serialize send/receive
     boost::asio::strand<boost::asio::any_io_executor> strand_;
+    /// TCP resolver
     tcp::resolver resolver_;
+    /// TCP socket
     tcp::socket socket_;
+    /// List of pending requests, waiting for a response (Message::refersTo)
     std::vector<std::weak_ptr<PendingRequest>> pendingRequests_;
+    /// unique request id to match a response
     uint16_t reqId_;
+    /// Server settings (host and port)
     ClientSettings::Server server_;
 
+    /// A pending request
     struct PendingMessage
     {
-        PendingMessage(const msg::message_ptr& msg, ResultHandler handler) : msg(msg), handler(handler)
+        /// C'tor
+        PendingMessage(msg::message_ptr msg, ResultHandler handler) : msg(std::move(msg)), handler(std::move(handler))
         {
         }
+        /// Pointer to the request
         msg::message_ptr msg;
+        /// Response handler
         ResultHandler handler;
     };
+
+    /// Pending messages to be sent
     std::deque<PendingMessage> messages_;
 };