diff --git a/include/fastdds/rtps/network/NetworkBuffer.hpp b/include/fastdds/rtps/network/NetworkBuffer.hpp
index f9f49db3e65..6048ec75aab 100644
--- a/include/fastdds/rtps/network/NetworkBuffer.hpp
+++ b/include/fastdds/rtps/network/NetworkBuffer.hpp
@@ -19,8 +19,7 @@
 #ifndef _FASTDDS_RTPS_NETWORK_NETWORKBUFFER_HPP
 #define _FASTDDS_RTPS_NETWORK_NETWORKBUFFER_HPP
 
-#include <cstdint>  // uint32_t
-#include <cstdlib>  // size_t
+#include <cstdint>
 #include <asio.hpp>
 
 namespace eprosima {
@@ -36,11 +35,11 @@ struct NetworkBuffer final
     //! Pointer to the buffer where the data is stored.
     const void* buffer;
     //! Number of bytes to use starting at @c buffer.
-    size_t size;
+    uint32_t size;
 
     NetworkBuffer(
             const void* ptr,
-            size_t s)
+            uint32_t s)
         : buffer(ptr)
         , size(s)
     {
@@ -54,7 +53,7 @@ struct NetworkBuffer final
 
     NetworkBuffer(
             const fastrtps::rtps::octet* ptr,
-            size_t s)
+            uint32_t s)
         : buffer(ptr)
         , size(s)
     {
diff --git a/src/cpp/rtps/messages/RTPSMessageGroup.cpp b/src/cpp/rtps/messages/RTPSMessageGroup.cpp
index 8565f64a5f5..558b93cc162 100644
--- a/src/cpp/rtps/messages/RTPSMessageGroup.cpp
+++ b/src/cpp/rtps/messages/RTPSMessageGroup.cpp
@@ -108,8 +108,8 @@ bool RTPSMessageGroup::append_submessage()
     // - If header_msg_ is not reseted, put submessage_msg_ into a new buffer and add it to buffers_to_send_
     //   Final msg Struct: | header_msg_ + submessage_msg_ | payload | padding | submessage_msg_ | payload | padding | ...
     //
-
-    if (participant_->security_attributes().is_rtps_protected)
+#if HAVE_SECURITY
+    if (protect_rtps = participant_->security_attributes().is_rtps_protected)
     {
         // If the RTPS message is protected, the whole message will be encrypted at once
         // so we need to keep the whole message in a single buffer
@@ -118,8 +118,11 @@ bool RTPSMessageGroup::append_submessage()
             EPROSIMA_LOG_ERROR(RTPS_WRITER, "Cannot add RTPS submesage to the CDRMessage. Buffer too small");
             return false;
         }
+        return true;
     }
-    else if (header_msg_->pos == RTPSMESSAGE_HEADER_SIZE && header_msg_->length == RTPSMESSAGE_HEADER_SIZE)
+#endif // if HAVE_SECURITY
+
+    if (header_msg_->pos == RTPSMESSAGE_HEADER_SIZE && header_msg_->length == RTPSMESSAGE_HEADER_SIZE)
     {
         // header_msg_ is reseted. This is the first submessage
         if (!append_message(participant_, header_msg_, submessage_msg_))
diff --git a/src/cpp/rtps/transport/TCPChannelResource.h b/src/cpp/rtps/transport/TCPChannelResource.h
index 673fd4956e3..8473472fcea 100644
--- a/src/cpp/rtps/transport/TCPChannelResource.h
+++ b/src/cpp/rtps/transport/TCPChannelResource.h
@@ -152,7 +152,7 @@ class TCPChannelResource : public ChannelResource
             const fastrtps::rtps::octet* header,
             size_t header_size,
             const fastrtps::rtps::octet* data,
-            size_t data_size,
+            uint32_t data_size,
             asio::error_code& ec)
     {
         NetworkBuffer buffers(data, data_size);
diff --git a/src/cpp/rtps/transport/test_UDPv4Transport.cpp b/src/cpp/rtps/transport/test_UDPv4Transport.cpp
index 6df9b8aac86..bf032d24045 100644
--- a/src/cpp/rtps/transport/test_UDPv4Transport.cpp
+++ b/src/cpp/rtps/transport/test_UDPv4Transport.cpp
@@ -494,6 +494,7 @@ bool test_UDPv4Transport::log_drop(
         const std::list<NetworkBuffer>& buffers,
         uint32_t size)
 {
+    static_cast<void>(size);
     if (test_UDPv4Transport_DropLog.size() < test_UDPv4Transport_DropLogLength)
     {
         vector<octet> message;