diff --git a/src/mhd2/Makefile.am b/src/mhd2/Makefile.am
index 1c1caab5..074a41d6 100644
--- a/src/mhd2/Makefile.am
+++ b/src/mhd2/Makefile.am
@@ -49,7 +49,7 @@ libmicrohttpd2_la_SOURCES = \
   mhd_lib_init.c            mhd_lib_init_impl.h       mhd_lib_init.h \
   mhd_lib_init_auto.h \
   mhd_dlinked_list.h \
-  mhd_connection.h \
+  mhd_conn_socket.h         mhd_connection.h \
   mhd_locks.h \
   mhd_itc.c                 mhd_itc.h                 mhd_itc_types.h \
   mhd_threads.c             mhd_threads.h             sys_thread_entry_type.h \
diff --git a/src/mhd2/conn_data_process.c b/src/mhd2/conn_data_process.c
index 7c873504..ec4e5368 100644
--- a/src/mhd2/conn_data_process.c
+++ b/src/mhd2/conn_data_process.c
@@ -57,7 +57,7 @@ mhd_conn_process_recv_send_data (struct MHD_Connection *restrict c)
     ((mhd_D_IS_USING_EDGE_TRIG (c->daemon)) ||
      (0 != (MHD_EVENT_LOOP_INFO_SEND & c->event_loop_info)));
   const bool has_sock_err =
-    (0 != (mhd_SOCKET_NET_STATE_ERROR_READY & c->sk_ready));
+    (0 != (mhd_SOCKET_NET_STATE_ERROR_READY & c->sk.ready));
   bool data_processed;
 
   data_processed = false;
@@ -65,9 +65,9 @@ mhd_conn_process_recv_send_data (struct MHD_Connection *restrict c)
   if (0 != (MHD_EVENT_LOOP_INFO_RECV & c->event_loop_info))
   {
     bool use_recv;
-    use_recv = (0 != (mhd_SOCKET_NET_STATE_RECV_READY & c->sk_ready));
+    use_recv = (0 != (mhd_SOCKET_NET_STATE_RECV_READY & c->sk.ready));
     use_recv = use_recv ||
-               (has_sock_err && c->sk_nonblck);
+               (has_sock_err && c->sk.props.is_nonblck);
 
     if (use_recv)
     {
@@ -89,11 +89,12 @@ mhd_conn_process_recv_send_data (struct MHD_Connection *restrict c)
     /* Assuming that after finishing receiving phase, connection send system
        buffers should have some space as sending was performed before receiving
        or has not been performed yet. */
-    use_send = (0 != (mhd_SOCKET_NET_STATE_SEND_READY & c->sk_ready));
+    use_send = (0 != (mhd_SOCKET_NET_STATE_SEND_READY & c->sk.ready));
     use_send = use_send ||
-               (data_processed && (! send_ready_state_known) && c->sk_nonblck);
+               (data_processed && (! send_ready_state_known)
+                && c->sk.props.is_nonblck);
     use_send = use_send ||
-               (has_sock_err && c->sk_nonblck);
+               (has_sock_err && c->sk.props.is_nonblck);
 
     if (use_send)
     {
@@ -142,7 +143,7 @@ mhd_conn_process_recv_send_data (struct MHD_Connection *restrict c)
      only for non-blocking sockets. */
   /* No need to check 'ret' as connection is always in
    * MHD_CONNECTION_CLOSED state if 'ret' is equal 'MHD_NO'. */
-  else if (on_fasttrack && c->sk_nonblck)
+  else if (on_fasttrack && c->sk.props.is_nonblck)
   {
     if (MHD_CONNECTION_HEADERS_SENDING == c->state)
     {
diff --git a/src/mhd2/conn_data_recv.c b/src/mhd2/conn_data_recv.c
index 1bb4a0da..6c94f6c9 100644
--- a/src/mhd2/conn_data_recv.c
+++ b/src/mhd2/conn_data_recv.c
@@ -53,8 +53,8 @@ mhd_conn_data_recv (struct MHD_Connection *restrict c,
   mhd_assert (NULL != c->read_buffer);
   mhd_assert (c->read_buffer_size > c->read_buffer_offset);
   mhd_assert (! has_err || \
-              (0 != (c->sk_ready & mhd_SOCKET_NET_STATE_ERROR_READY)));
-  mhd_assert ((0 == (c->sk_ready & mhd_SOCKET_NET_STATE_ERROR_READY)) || \
+              (0 != (c->sk.ready & mhd_SOCKET_NET_STATE_ERROR_READY)));
+  mhd_assert ((0 == (c->sk.ready & mhd_SOCKET_NET_STATE_ERROR_READY)) || \
               has_err);
 
   // TODO: TLS support: handshake/transport layer
@@ -69,10 +69,10 @@ mhd_conn_data_recv (struct MHD_Connection *restrict c,
     /* Handle errors */
     if ((mhd_SOCKET_ERR_NO_ERROR == res) && (0 == received))
     {
-      c->sk_rmt_shut_wr = true;
+      c->sk.state.rmt_shut_wr = true;
       res = mhd_SOCKET_ERR_REMT_DISCONN;
     }
-    if (has_err && ! mhd_SOCKET_ERR_IS_HARD (res) && c->sk_nonblck)
+    if (has_err && ! mhd_SOCKET_ERR_IS_HARD (res) && c->sk.props.is_nonblck)
     {
       /* Re-try last time to detect the error */
       uint_fast64_t dummy_buf;
@@ -80,16 +80,16 @@ mhd_conn_data_recv (struct MHD_Connection *restrict c,
     }
     if (mhd_SOCKET_ERR_IS_HARD (res))
     {
-      c->sk_discnt_err = res;
-      c->sk_ready =
-        (enum mhd_SocketNetState) (((unsigned int) c->sk_ready)
+      c->sk.state.discnt_err = res;
+      c->sk.ready =
+        (enum mhd_SocketNetState) (((unsigned int) c->sk.ready)
                                    | mhd_SOCKET_NET_STATE_ERROR_READY);
     }
     return;
   }
 
   if (0 == received)
-    c->sk_rmt_shut_wr = true;
+    c->sk.state.rmt_shut_wr = true;
 
   c->read_buffer_offset += received;
   mhd_stream_update_activity_mark (c); // TODO: centralise activity update
@@ -132,7 +132,7 @@ if ((bytes_read < 0) || socket_error)
 #if 0 // TODO: handle remote shut WR
 if (0 == bytes_read)
 { /* Remote side closed c. */   // FIXME: Actually NOT!
-  c->sk_rmt_shut_wr = true;
+  c->sk.state.rmt_shut_wr = true;
   if ( (MHD_CONNECTION_INIT < c->state) &&
        (MHD_CONNECTION_FULL_REQ_RECEIVED > c->state) )
   {
diff --git a/src/mhd2/conn_data_send.c b/src/mhd2/conn_data_send.c
index ca27decc..ad90a6be 100644
--- a/src/mhd2/conn_data_send.c
+++ b/src/mhd2/conn_data_send.c
@@ -343,9 +343,9 @@ mhd_conn_data_send (struct MHD_Connection *restrict c)
   }
   else if (mhd_SOCKET_ERR_IS_HARD (res))
   {
-    c->sk_discnt_err = res;
-    c->sk_ready =
-      (enum mhd_SocketNetState) (((unsigned int) c->sk_ready)
+    c->sk.state.discnt_err = res;
+    c->sk.ready =
+      (enum mhd_SocketNetState) (((unsigned int) c->sk.ready)
                                  | mhd_SOCKET_NET_STATE_ERROR_READY);
   }
 }
diff --git a/src/mhd2/daemon_add_conn.c b/src/mhd2/daemon_add_conn.c
index d17e9016..16018179 100644
--- a/src/mhd2/daemon_add_conn.c
+++ b/src/mhd2/daemon_add_conn.c
@@ -168,18 +168,18 @@ new_connection_prepare_ (struct MHD_Daemon *restrict daemon,
 
   if (! external_add)
   {
-    connection->sk_corked = mhd_T_NO;
-    connection->sk_nodelay = mhd_T_NO;
+    connection->sk.state.corked = mhd_T_NO;
+    connection->sk.state.nodelay = mhd_T_NO;
   }
   else
   {
-    connection->sk_corked = mhd_T_MAYBE;
-    connection->sk_nodelay = mhd_T_MAYBE;
+    connection->sk.state.corked = mhd_T_MAYBE;
+    connection->sk.state.nodelay = mhd_T_MAYBE;
   }
 
   if (0 < addrlen)
   {
-    if (NULL == (connection->addr = malloc (addrlen)))
+    if (NULL == (connection->sk.addr.data = malloc (addrlen)))
     {
       mhd_LOG_MSG (daemon, MHD_SC_CONNECTION_MALLOC_FAILURE,
                    "Failed to allocate memory for the new connection");
@@ -187,17 +187,17 @@ new_connection_prepare_ (struct MHD_Daemon *restrict daemon,
       free (connection);
       return MHD_SC_CONNECTION_MALLOC_FAILURE;
     }
-    memcpy (connection->addr,
+    memcpy (connection->sk.addr.data,
             addr,
             addrlen);
   }
   else
-    connection->addr = NULL;
-  connection->addr_len = addrlen;
-  connection->socket_fd = client_socket;
-  connection->sk_nonblck = non_blck;
-  connection->is_nonip = sk_is_nonip;
-  connection->sk_spipe_suppress = sk_spipe_supprs;
+    connection->sk.addr.data = NULL;
+  connection->sk.addr.size = addrlen;
+  connection->sk.fd = client_socket;
+  connection->sk.props.is_nonblck = non_blck;
+  connection->sk.props.is_nonip = sk_is_nonip;
+  connection->sk.props.has_spipe_supp = sk_spipe_supprs;
 #ifdef MHD_USE_THREADS
   mhd_thread_handle_ID_set_invalid (&connection->tid);
 #endif /* MHD_USE_THREADS */
@@ -317,7 +317,7 @@ new_connection_process_ (struct MHD_Daemon *restrict daemon,
           event.data.ptr = connection;
           if (0 != epoll_ctl (daemon->events.data.epoll.e_fd,
                               EPOLL_CTL_ADD,
-                              connection->socket_fd,
+                              connection->sk.fd,
                               &event))
           {
             mhd_LOG_MSG (daemon, MHD_SC_EPOLL_CTL_ADD_FAILED,
@@ -328,7 +328,7 @@ new_connection_process_ (struct MHD_Daemon *restrict daemon,
           {
             if (0) // TODO: implement turbo
             {
-              connection->sk_ready = mhd_SOCKET_NET_STATE_RECV_READY
+              connection->sk.ready = mhd_SOCKET_NET_STATE_RECV_READY
                                      | mhd_SOCKET_NET_STATE_SEND_READY;
               mhd_conn_mark_ready (connection, daemon);
             }
@@ -360,9 +360,9 @@ new_connection_process_ (struct MHD_Daemon *restrict daemon,
 
   // TODO: per IP limit
 
-  if (NULL != connection->addr)
-    free (connection->addr);
-  (void) mhd_socket_close (connection->socket_fd);
+  if (NULL != connection->sk.addr.data)
+    free (connection->sk.addr.data);
+  (void) mhd_socket_close (connection->sk.fd);
   free (connection);
   mhd_assert (MHD_SC_OK != res);
   return res;  /* *** Function failure exit point *** */
@@ -543,8 +543,8 @@ MHD_daemon_add_connection (struct MHD_Daemon *daemon,
         return MHD_SC_CONFIGURATION_WRONG_SA_SIZE;
       }
 #ifdef HAVE_STRUCT_SOCKADDR_SA_LEN
-      if ((0 != addr->sa_len) &&
-          (sizeof(struct sockaddr_in) > (size_t) addr->sa_len) )
+      if ((0 != sk.addr.data->sa_len) &&
+          (sizeof(struct sockaddr_in) > (size_t) sk.addr.data->sa_len) )
       {
         mhd_LOG_MSG (daemon, MHD_SC_CONFIGURATION_WRONG_SA_SIZE, \
                      "MHD_add_connection() has been called with " \
@@ -567,8 +567,8 @@ MHD_daemon_add_connection (struct MHD_Daemon *daemon,
         return MHD_SC_CONFIGURATION_WRONG_SA_SIZE;
       }
 #ifdef HAVE_STRUCT_SOCKADDR_SA_LEN
-      if ((0 != addr->sa_len) &&
-          (sizeof(struct sockaddr_in6) > (size_t) addr->sa_len) )
+      if ((0 != sk.addr.data->sa_len) &&
+          (sizeof(struct sockaddr_in6) > (size_t) sk.addr.data->sa_len) )
       {
         mhd_LOG_MSG (daemon, MHD_SC_CONFIGURATION_WRONG_SA_SIZE, \
                      "MHD_add_connection() has been called with " \
@@ -580,9 +580,9 @@ MHD_daemon_add_connection (struct MHD_Daemon *daemon,
 #endif /* HAVE_STRUCT_SOCKADDR_SA_LEN */
     }
 #ifdef HAVE_STRUCT_SOCKADDR_SA_LEN
-    if ((0 != addr->sa_len) &&
-        (addrlen > (size_t) addr->sa_len))
-      addrlen = (size_t) addr->sa_len;   /* Use safest value */
+    if ((0 != sk.addr.data->sa_len) &&
+        (addrlen > (size_t) sk.addr.data->sa_len))
+      addrlen = (size_t) sk.addr.data->sa_len;   /* Use safest value */
 #endif /* HAVE_STRUCT_SOCKADDR_SA_LEN */
 #endif /* HAVE_INET6 */
   }
@@ -975,9 +975,9 @@ mhd_conn_close_final (struct MHD_Connection *restrict c)
   mhd_assert (c != mhd_DLINKEDL_GET_FIRST (&(c->daemon->conns), all_conn));
   mhd_assert (c != mhd_DLINKEDL_GET_LAST (&(c->daemon->conns), all_conn));
 
-  if (NULL != c->addr)
-    free (c->addr);
-  mhd_socket_close (c->socket_fd);
+  if (NULL != c->sk.addr.data)
+    free (c->sk.addr.data);
+  mhd_socket_close (c->sk.fd);
 
   free (c);
 }
diff --git a/src/mhd2/events_process.c b/src/mhd2/events_process.c
index 1f299596..55bc30b3 100644
--- a/src/mhd2/events_process.c
+++ b/src/mhd2/events_process.c
@@ -101,10 +101,10 @@ update_conn_net_status (struct MHD_Daemon *restrict d,
   if (err_state)
     sk_state = (enum mhd_SocketNetState)
                (sk_state | (unsigned int) mhd_SOCKET_NET_STATE_ERROR_READY);
-  c->sk_ready = sk_state;
+  c->sk.ready = sk_state;
 
   if ((0 !=
-       (((unsigned int) c->sk_ready) & ((unsigned int) c->event_loop_info)
+       (((unsigned int) c->sk.ready) & ((unsigned int) c->event_loop_info)
         & (MHD_EVENT_LOOP_INFO_RECV | MHD_EVENT_LOOP_INFO_SEND)))
       || err_state)
     mhd_conn_mark_ready (c, d);
@@ -470,16 +470,16 @@ select_update_fdsets (struct MHD_Daemon *restrict d,
       continue;
 
     if (0 != (c->event_loop_info & MHD_EVENT_LOOP_INFO_RECV))
-      fd_set_wrap (c->socket_fd,
+      fd_set_wrap (c->sk.fd,
                    rfds,
                    &ret,
                    d);
     if (0 != (c->event_loop_info & MHD_EVENT_LOOP_INFO_SEND))
-      fd_set_wrap (c->socket_fd,
+      fd_set_wrap (c->sk.fd,
                    wfds,
                    &ret,
                    d);
-    fd_set_wrap (c->socket_fd,
+    fd_set_wrap (c->sk.fd,
                  efds,
                  &ret,
                  d);
@@ -575,7 +575,7 @@ select_update_statuses_from_fdsets (struct MHD_Daemon *d,
     if (is_conn_excluded_from_http_comm (c))
       continue;
 
-    sk = c->socket_fd;
+    sk = c->sk.fd;
     recv_ready = FD_ISSET (sk, rfds);
     send_ready = FD_ISSET (sk, wfds);
     err_state = FD_ISSET (sk, efds);
@@ -737,7 +737,7 @@ poll_update_fds (struct MHD_Daemon *restrict d,
     mhd_assert (i_c < d->dbg.num_events_elements);
     mhd_assert (MHD_CONNECTION_CLOSED != c->state);
 
-    d->events.data.poll.fds[i_c].fd = c->socket_fd;
+    d->events.data.poll.fds[i_c].fd = c->sk.fd;
     d->events.data.poll.rel[i_c].connection = c;
     events = 0;
     if (0 != (c->event_loop_info & MHD_EVENT_LOOP_INFO_RECV))
@@ -846,7 +846,7 @@ poll_update_statuses_from_fds (struct MHD_Daemon *restrict d,
 
     c = d->events.data.poll.rel[i_c].connection;
     mhd_assert (! is_conn_excluded_from_http_comm (c));
-    mhd_assert (c->socket_fd == d->events.data.poll.fds[i_c].fd);
+    mhd_assert (c->sk.fd == d->events.data.poll.fds[i_c].fd);
     revents = d->events.data.poll.fds[i_c].revents;
     recv_ready = (0 != (revents & (MHD_POLL_IN | POLLIN)));
     send_ready = (0 != (revents & (MHD_POLL_OUT | POLLOUT)));
diff --git a/src/mhd2/mhd_conn_socket.h b/src/mhd2/mhd_conn_socket.h
new file mode 100644
index 00000000..66ea0285
--- /dev/null
+++ b/src/mhd2/mhd_conn_socket.h
@@ -0,0 +1,169 @@
+/*
+  This file is part of GNU libmicrohttpd
+  Copyright (C) 2024 Evgeny Grin (Karlson2k)
+
+  GNU libmicrohttpd is free software; you can redistribute it and/or
+  modify it under the terms of the GNU Lesser General Public
+  License as published by the Free Software Foundation; either
+  version 2.1 of the License, or (at your option) any later version.
+
+  GNU libmicrohttpd is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+  Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public
+  License along with this library; if not, write to the Free Software
+  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+
+*/
+
+/**
+ * @file src/mhd2/mhd_conn_socket.h
+ * @brief  The definition of the connection-specific socket data
+ * @author Karlson2k (Evgeny Grin)
+ */
+
+#ifndef MHD_CONN_SOCKET_H
+#define MHD_CONN_SOCKET_H 1
+
+#include "mhd_sys_options.h"
+
+#include "sys_bool_type.h"
+
+#include "mhd_socket_type.h"
+#include "mhd_tristate.h"
+#include "mhd_socket_error.h"
+
+
+struct sockaddr_storage; /* Forward declaration */
+
+/**
+ * The network states for connected sockets
+ * An internal version of #MHD_FdState. Keep in sync!
+ */
+enum MHD_FIXED_FLAGS_ENUM_ mhd_SocketNetState
+{
+  /**
+   * No active states of the socket
+   */
+  mhd_SOCKET_NET_STATE_NOTHING = 0
+  ,
+  /**
+   * The socket is ready for receiving
+   */
+  mhd_SOCKET_NET_STATE_RECV_READY = 1 << 0
+  ,
+  /**
+   * The socket is ready for sending
+   */
+  mhd_SOCKET_NET_STATE_SEND_READY = 1 << 1
+  ,
+  /**
+   * The socket has some unrecoverable error
+   */
+  mhd_SOCKET_NET_STATE_ERROR_READY = 1 << 2
+};
+
+/**
+ * Connection-specific socket state data
+ */
+struct mhd_ConnSocketState
+{
+  /**
+   * The current state of TCP_NODELAY socket setting
+   */
+  enum mhd_Tristate nodelay;
+
+// #ifndef MHD_SOCKETS_KIND_WINSOCK // TODO: conditionally use in the code
+  /**
+   * The current state of TCP_CORK / TCP_NOPUSH socket setting
+   */
+  enum mhd_Tristate corked;
+// #endif
+
+  /**
+   * Set to 'true' when the remote side shut down write/send and
+   * __the last byte from the remote has been read__.
+   */
+  bool rmt_shut_wr;
+
+  /**
+   * The type of the error when the socket disconnected early
+   */
+  enum mhd_SocketError discnt_err;
+};
+
+/**
+ * Connection-specific socket properties
+ */
+struct mhd_ConnSocketProperties
+{
+  /**
+   * The type of the socket: TCP/IP or non TCP/IP (a UNIX domain socket, a pipe)
+   */
+  enum mhd_Tristate is_nonip;
+
+  /**
+   * true if the socket is non-blocking, false otherwise.
+   */
+  bool is_nonblck;
+
+  /**
+   * true if the socket has set SIGPIPE suppression
+   */
+  bool has_spipe_supp;
+};
+
+
+/**
+ * The connection socket remote address information
+ */
+struct mhd_ConnSocketAddr
+{
+  /**
+   * The remote address.
+   * Allocated by malloc() (not in the connection memory pool!).
+   * Could be NULL if the address is not known.
+   */
+  struct sockaddr_storage *data;
+
+  /**
+   * The size of the address pointed by @a data.
+   * Zero is @a data is NULL.
+   */
+  size_t size;
+};
+
+/**
+ * Connection-specific socket data
+ */
+struct mhd_ConnSocket
+{
+  /**
+   * The network socket.
+   */
+  MHD_Socket fd;
+
+  /**
+   * Connection-specific socket state data
+   */
+  struct mhd_ConnSocketState state;
+
+  /**
+   * The receive / send / error readiness the socket
+   */
+  enum mhd_SocketNetState ready;
+
+  /**
+   * Connection-specific socket properties
+   */
+  struct mhd_ConnSocketProperties props;
+
+  /**
+   * The connection socket remote address information
+   */
+  struct mhd_ConnSocketAddr addr;
+};
+
+#endif /* ! MHD_CONN_SOCKET_H */
diff --git a/src/mhd2/mhd_connection.h b/src/mhd2/mhd_connection.h
index be6c3f60..9e738528 100644
--- a/src/mhd2/mhd_connection.h
+++ b/src/mhd2/mhd_connection.h
@@ -37,7 +37,8 @@
 
 #include "sys_bool_type.h"
 #include "sys_base_types.h"
-#include "mhd_socket_type.h"
+
+#include "mhd_conn_socket.h"
 
 #include "mhd_threads.h"
 
@@ -114,81 +115,53 @@ enum MHD_FIXED_FLAGS_ENUM_ MHD_ConnectionEventLoopInfo
 
 
 /**
- * The network states for connected sockets
- * An internal version of #MHD_FdState. Keep in sync!
+ * The reason for the connection closure
  */
-enum MHD_FIXED_FLAGS_ENUM_ mhd_SocketNetState
-{
-  /**
-   * No active states of the socket
-   */
-  mhd_SOCKET_NET_STATE_NOTHING = 0
-  ,
-  /**
-   * The socket is ready for receiving
-   */
-  mhd_SOCKET_NET_STATE_RECV_READY = 1 << 0
-  ,
-  /**
-   * The socket is ready for sending
-   */
-  mhd_SOCKET_NET_STATE_SEND_READY = 1 << 1
-  ,
-  /**
-   * The socket has some unrecoverable error
-   */
-  mhd_SOCKET_NET_STATE_ERROR_READY = 1 << 2
-};
-
-
-/**
- * The reason for the socket closure
- */
-enum mhd_SocketClosureReason
+enum mhd_ConnClosureReason
 {
   /**
    * The socket is not closed / closing.
    */
-  mhd_SCOKET_CLOSURE_REASON_NO_CLOSURE = 0
+  mhd_CONN_CLOSURE_REASON_NO_CLOSURE = 0
   ,
   /**
    * Socket has to be closed because HTTP protocol successfully finished data
    * exchange.
    */
-  mhd_SCOKET_CLOSURE_REASON_PROTOCOL_SUCCESS
+  mhd_CONN_CLOSURE_REASON_PROTOCOL_SUCCESS
   ,
   /**
    * Socket has to be closed because remote side violated some HTTP
    * specification requirements or request processed with an error.
    * The HTTP error response should be sent.
    */
-  mhd_SCOKET_CLOSURE_REASON_PROTOCOL_FAILURE_SOFT
+  mhd_CONN_CLOSURE_REASON_PROTOCOL_FAILURE_SOFT
   ,
   /**
    * Timeout expired
    */
-  mhd_SCOKET_CLOSURE_REASON_TIMEOUT
+  mhd_CONN_CLOSURE_REASON_TIMEOUT
   ,
   /**
    * Socket has to be closed because received data cannot be interpreted as
    * valid HTTP data.
    */
-  mhd_SCOKET_CLOSURE_REASON_PROTOCOL_FAILURE_HARD
+  mhd_CONN_CLOSURE_REASON_PROTOCOL_FAILURE_HARD
   ,
   /**
    * Unrecoverable TLS error
    */
-  mhd_SCOKET_CLOSURE_REASON_TLS_ERROR
+  mhd_CONN_CLOSURE_REASON_TLS_ERROR
   ,
   /**
    * The remote side closed connection in abortive way
    */
-  mhd_SCOKET_CLOSURE_REASON_REMOTE_HARD_DISCONN
+  mhd_CONN_CLOSURE_REASON_REMOTE_HARD_DISCONN
   ,
   /**
    * The connection has been broken for some reason
    */
-  mhd_SCOKET_CLOSURE_REASON_CONN_BROKEN
+  mhd_CONN_CLOSURE_REASON_CONN_BROKEN
 };
 
 /**
@@ -423,20 +396,9 @@ struct MHD_Connection
   mhd_DLNKDL_LINKS (MHD_Connection,all_conn);
 
   /**
-   * The state of the connected socket
+   * The connection socket data
    */
-  enum mhd_SocketNetState sk_ready;
-
-  /**
-   * The type of the error when disconnected early
-   */
-  enum mhd_SocketError sk_discnt_err;
-
-  /**
-   * Set to 'true' when the client shut down write/send and
-   * __the last byte from the remote has been read__.
-   */
-  bool sk_rmt_shut_wr;
+  struct mhd_ConnSocket sk;
 
   /**
    * 'true' if connection is in 'process ready' list,
@@ -530,12 +492,6 @@ struct MHD_Connection
    */
   char *write_buffer;
 
-  /**
-   * Foreign address (of length @e addr_len).  MALLOCED (not
-   * in pool!).
-   */
-  struct sockaddr_storage *addr;
-
 #if defined(MHD_USE_THREADS)
   /**
    * Thread handle for this connection (if we are using
@@ -579,11 +535,6 @@ struct MHD_Connection
    */
   size_t continue_message_write_offset;
 
-  /**
-   * Length of the foreign address.
-   */
-  size_t addr_len;
-
   /**
    * Last time this connection had any activity
    * (reading or writing).
@@ -597,40 +548,6 @@ struct MHD_Connection
    */
   uint_fast64_t connection_timeout_ms;
 
-  /**
-   * Socket for this connection.  Set to #MHD_INVALID_SOCKET if
-   * this connection has died (daemon should clean
-   * up in that case).
-   */
-  MHD_Socket socket_fd;
-
-  /**
-   * The type of the socket: TCP/IP or non TCP/IP (a UNIX domain socket, a pipe)
-   */
-  enum mhd_Tristate is_nonip;
-
-  /**
-   * true if @a socket_fd is non-blocking, false otherwise.
-   */
-  bool sk_nonblck;
-
-  /**
-   * true if connection socket has set SIGPIPE suppression
-   */
-  bool sk_spipe_suppress;
-
-// #ifndef MHD_SOCKETS_KIND_WINSOCK // TODO: conditionally use in the code
-  /**
-   * Tracks TCP_CORK / TCP_NOPUSH of the connection socket.
-   */
-  enum mhd_Tristate sk_corked;
-// #endif
-
-  /**
-   * Tracks TCP_NODELAY state of the connection socket.
-   */
-  enum mhd_Tristate sk_nodelay;
-
   /**
    * Some error happens during processing the connection therefore this
    * connection must be closed.
diff --git a/src/mhd2/mhd_recv.c b/src/mhd2/mhd_recv.c
index 979e4b53..27b2cdda 100644
--- a/src/mhd2/mhd_recv.c
+++ b/src/mhd2/mhd_recv.c
@@ -52,13 +52,13 @@ mhd_plain_recv (struct MHD_Connection *restrict c,
   if (MHD_SCKT_SEND_MAX_SIZE_ < buf_size)
     buf_size = MHD_SCKT_SEND_MAX_SIZE_;
 
-  res = mhd_sys_recv (c->socket_fd, buf, buf_size);
+  res = mhd_sys_recv (c->sk.fd, buf, buf_size);
   if (0 <= res)
   {
     *received = (size_t) res;
     if (buf_size > (size_t) res)
-      c->sk_ready = (enum mhd_SocketNetState) /* Clear 'recv-ready' */
-                    (((unsigned int) c->sk_ready)
+      c->sk.ready = (enum mhd_SocketNetState) /* Clear 'recv-ready' */
+                    (((unsigned int) c->sk.ready)
                      & (~(enum mhd_SocketNetState)
                         mhd_SOCKET_NET_STATE_RECV_READY));
     return mhd_SOCKET_ERR_NO_ERROR; /* Success exit point */
@@ -67,8 +67,8 @@ mhd_plain_recv (struct MHD_Connection *restrict c,
   err = mhd_socket_error_get_from_sys_err (mhd_SCKT_GET_LERR ());
 
   if (mhd_SOCKET_ERR_AGAIN == err)
-    c->sk_ready = (enum mhd_SocketNetState) /* Clear 'recv-ready' */
-                  (((unsigned int) c->sk_ready)
+    c->sk.ready = (enum mhd_SocketNetState) /* Clear 'recv-ready' */
+                  (((unsigned int) c->sk.ready)
                    & (~(enum mhd_SocketNetState)
                       mhd_SOCKET_NET_STATE_RECV_READY));
 
@@ -83,7 +83,7 @@ mhd_recv (struct MHD_Connection *restrict c,
           char buf[MHD_FN_PAR_DYN_ARR_SIZE_ (buf_size)],
           size_t *restrict received)
 {
-  mhd_assert (MHD_INVALID_SOCKET != c->socket_fd);
+  mhd_assert (MHD_INVALID_SOCKET != c->sk.fd);
   mhd_assert (MHD_CONNECTION_CLOSED != c->state);
 
   // TODO: implement TLS support
diff --git a/src/mhd2/mhd_recv.h b/src/mhd2/mhd_recv.h
index c6a79c8d..17dc57da 100644
--- a/src/mhd2/mhd_recv.h
+++ b/src/mhd2/mhd_recv.h
@@ -36,7 +36,7 @@ struct MHD_Connection; /* forward declaration */
 
 /**
  * Receive the data from the network socket.
- * Clear #mhd_SOCKET_NET_STATE_RECV_READY in sk_ready if necessary.
+ * Clear #mhd_SOCKET_NET_STATE_RECV_READY in sk.ready if necessary.
  *
  * @param c the connection to use
  * @param buf_size the size of the @a buf buffer
diff --git a/src/mhd2/mhd_send.c b/src/mhd2/mhd_send.c
index 7ab652b5..cc61c3e9 100644
--- a/src/mhd2/mhd_send.c
+++ b/src/mhd2/mhd_send.c
@@ -198,26 +198,26 @@ mhd_connection_set_nodelay_state (struct MHD_Connection *connection,
   static const mhd_SCKT_OPT_BOOL on_val = 1;
   int err_code;
 
-  if (mhd_T_IS_YES (connection->is_nonip))
+  if (mhd_T_IS_YES (connection->sk.props.is_nonip))
     return false;
 
-  if (0 == setsockopt (connection->socket_fd,
+  if (0 == setsockopt (connection->sk.fd,
                        IPPROTO_TCP,
                        TCP_NODELAY,
                        (const void *) (nodelay_state ? &on_val : &off_val),
                        sizeof (off_val)))
   {
-    connection->sk_nodelay = nodelay_state ? mhd_T_YES : mhd_T_NO;
+    connection->sk.state.nodelay = nodelay_state ? mhd_T_YES : mhd_T_NO;
     return true;
   }
 
   err_code = mhd_SCKT_GET_LERR ();
-  if ((mhd_T_IS_NOT_YES (connection->is_nonip)) &&
+  if ((mhd_T_IS_NOT_YES (connection->sk.props.is_nonip)) &&
       (mhd_SCKT_ERR_IS_EINVAL (err_code) ||
        mhd_SCKT_ERR_IS_NOPROTOOPT (err_code) ||
        mhd_SCKT_ERR_IS_NOTSOCK (err_code)))
   {
-    connection->is_nonip = mhd_T_YES;
+    connection->sk.props.is_nonip = mhd_T_YES;
   }
   else
   {
@@ -226,7 +226,7 @@ mhd_connection_set_nodelay_state (struct MHD_Connection *connection,
   }
 #else  /* ! TCP_NODELAY */
   (void) nodelay_state; /* Mute compiler warnings */
-  connection->sk_nodelay = mhd_T_NO;
+  connection->sk.state.nodelay = mhd_T_NO;
 #endif /* ! TCP_NODELAY */
   return false;
 }
@@ -241,26 +241,26 @@ mhd_connection_set_cork_state (struct MHD_Connection *connection,
   static const mhd_SCKT_OPT_BOOL on_val = 1;
   int err_code;
 
-  if (mhd_T_IS_YES (connection->is_nonip))
+  if (mhd_T_IS_YES (connection->sk.props.is_nonip))
     return false;
 
-  if (0 == setsockopt (connection->socket_fd,
+  if (0 == setsockopt (connection->sk.fd,
                        IPPROTO_TCP,
                        mhd_TCP_CORK_NOPUSH,
                        (const void *) (cork_state ? &on_val : &off_val),
                        sizeof (off_val)))
   {
-    connection->sk_corked = cork_state ? mhd_T_YES : mhd_T_NO;
+    connection->sk.state.corked = cork_state ? mhd_T_YES : mhd_T_NO;
     return true;
   }
 
   err_code = mhd_SCKT_GET_LERR ();
-  if ((mhd_T_IS_NOT_YES (connection->is_nonip)) &&
+  if ((mhd_T_IS_NOT_YES (connection->sk.props.is_nonip)) &&
       (mhd_SCKT_ERR_IS_EINVAL (err_code) ||
        mhd_SCKT_ERR_IS_NOPROTOOPT (err_code) ||
        mhd_SCKT_ERR_IS_NOTSOCK (err_code)))
   {
-    connection->is_nonip = mhd_T_YES;
+    connection->sk.props.is_nonip = mhd_T_YES;
   }
   else
   {
@@ -275,7 +275,7 @@ mhd_connection_set_cork_state (struct MHD_Connection *connection,
 
 #else  /* ! mhd_TCP_CORK_NOPUSH */
   (void) cork_state; /* Mute compiler warnings. */
-  connection->sk_corked = mhd_T_NO;
+  connection->sk.state.corked = mhd_T_NO;
 #endif /* ! mhd_TCP_CORK_NOPUSH */
   return false;
 }
@@ -300,7 +300,7 @@ pre_send_setopt (struct MHD_Connection *connection,
    * Final piece is indicated by push_data == true. */
   const bool buffer_data = (! push_data);
 
-  if (mhd_T_IS_YES (connection->is_nonip))
+  if (mhd_T_IS_YES (connection->sk.props.is_nonip))
     return;
 
   // TODO: support inheriting of TCP_NODELAY and TCP_NOPUSH
@@ -322,7 +322,7 @@ pre_send_setopt (struct MHD_Connection *connection,
 #endif /* ! mhd_USE_MSG_MORE */
 
 #ifdef mhd_TCP_CORK_NOPUSH
-    if (mhd_T_IS_YES (connection->sk_corked))
+    if (mhd_T_IS_YES (connection->sk.state.corked))
       return; /* The connection was already corked. */
 
     /* Prefer 'cork' over 'no delay' as the 'cork' buffers better, regardless
@@ -333,7 +333,7 @@ pre_send_setopt (struct MHD_Connection *connection,
     /* Failed to cork the connection.
      * Really unlikely to happen on TCP connections. */
 #endif /* mhd_TCP_CORK_NOPUSH */
-    if (mhd_T_IS_NO (connection->sk_nodelay))
+    if (mhd_T_IS_NO (connection->sk.state.nodelay))
       return; /* TCP_NODELAY was not set for the socket.
                * Nagle's algorithm will buffer some data. */
 
@@ -397,17 +397,17 @@ pre_send_setopt (struct MHD_Connection *connection,
   /* This is typical modern FreeBSD and OpenBSD behaviour. */
 #        endif /* ! mhd_NODELAY_SET_PUSH_DATA */
 
-  if (mhd_T_IS_YES (connection->sk_corked))
+  if (mhd_T_IS_YES (connection->sk.state.corked))
     return; /* Socket is corked. Data can be pushed by resetting of
              * TCP_CORK / TCP_NOPUSH after send() */
-  else if (mhd_T_IS_NO (connection->sk_corked))
+  else if (mhd_T_IS_NO (connection->sk.state.corked))
   {
     /* The socket is not corked. */
-    if (mhd_T_IS_YES (connection->sk_nodelay))
+    if (mhd_T_IS_YES (connection->sk.state.nodelay))
       return; /* TCP_NODELAY was already set,
                * data will be pushed automatically by the next send() */
 #        ifdef mhd_NODELAY_SET_PUSH_DATA
-    else if (mhd_T_IS_MAYBE (connection->sk_nodelay))
+    else if (mhd_T_IS_MAYBE (connection->sk.state.nodelay))
     {
       /* Setting TCP_NODELAY may push data NOW.
        * Cork socket here and uncork after send(). */
@@ -470,7 +470,7 @@ pre_send_setopt (struct MHD_Connection *connection,
              * TCP_CORK / TCP_NOPUSH after send() */
   /* The socket cannot be corked.
    * Really unlikely to happen on TCP connections */
-  if (mhd_T_IS_YES (connection->sk_nodelay))
+  if (mhd_T_IS_YES (connection->sk.state.nodelay))
     return; /* TCP_NODELAY was already set,
              * data will be pushed by the next send() */
 
@@ -499,11 +499,11 @@ pre_send_setopt (struct MHD_Connection *connection,
   /* This is old FreeBSD and Darwin behaviour. */
 
   /* Uncork socket if socket wasn't uncorked. */
-  if (mhd_T_IS_NOT_NO (connection->sk_corked))
+  if (mhd_T_IS_NOT_NO (connection->sk.state.corked))
     mhd_connection_set_cork_state (connection, false);
 
   /* Set TCP_NODELAY if it wasn't set. */
-  if (mhd_T_IS_NOT_YES (connection->sk_nodelay))
+  if (mhd_T_IS_NOT_YES (connection->sk.state.nodelay))
     mhd_connection_set_nodelay_state (connection, true);
 
   return;
@@ -525,7 +525,7 @@ pre_send_setopt (struct MHD_Connection *connection,
   /* Buffering of data is controlled only by
    * Nagel's algorithm. */
   /* Set TCP_NODELAY if it wasn't set. */
-  if (mhd_T_IS_NOT_YES (connection->sk_nodelay))
+  if (mhd_T_IS_NOT_YES (connection->sk.state.nodelay))
     mhd_connection_set_nodelay_state (connection, true);
 #endif /* ! mhd_TCP_CORK_NOPUSH */
 }
@@ -548,11 +548,11 @@ zero_send (struct MHD_Connection *connection)
 {
   static const int dummy = 0;
 
-  if (mhd_T_IS_YES (connection->is_nonip))
+  if (mhd_T_IS_YES (connection->sk.props.is_nonip))
     return false;
-  mhd_assert (mhd_T_IS_NO (connection->sk_corked));
-  mhd_assert (mhd_T_IS_YES (connection->sk_nodelay));
-  if (0 == mhd_sys_send (connection->socket_fd, &dummy, 0))
+  mhd_assert (mhd_T_IS_NO (connection->sk.state.corked));
+  mhd_assert (mhd_T_IS_YES (connection->sk.state.nodelay));
+  if (0 == mhd_sys_send (connection->sk.fd, &dummy, 0))
     return true;
   mhd_LOG_MSG (connection->daemon, MHD_SC_SOCKET_ZERO_SEND_FAILED, \
                "Failed to push the data by zero-sized send.");
@@ -581,7 +581,7 @@ post_send_setopt (struct MHD_Connection *connection,
    * Final piece is indicated by push_data == true. */
   const bool buffer_data = (! push_data);
 
-  if (mhd_T_IS_YES (connection->is_nonip))
+  if (mhd_T_IS_YES (connection->sk.props.is_nonip))
     return;
   if (buffer_data)
     return; /* Nothing to do after the send(). */
@@ -592,8 +592,8 @@ post_send_setopt (struct MHD_Connection *connection,
 
   /* Need to push data. */
 #ifdef mhd_TCP_CORK_NOPUSH
-  if (mhd_T_IS_YES (connection->sk_nodelay) && \
-      mhd_T_IS_NO (connection->sk_corked))
+  if (mhd_T_IS_YES (connection->sk.state.nodelay) && \
+      mhd_T_IS_NO (connection->sk.state.corked))
     return; /* Data has been already pushed by last send(). */
 
 #  ifdef mhd_CORK_RESET_PUSH_DATA_ALWAYS
@@ -620,7 +620,7 @@ post_send_setopt (struct MHD_Connection *connection,
    * resetting of TCP_CORK so next final send without MSG_MORE will push
    * data to the network (without additional sys-call to push data).  */
 
-  if (mhd_T_IS_NOT_YES (connection->sk_nodelay) ||
+  if (mhd_T_IS_NOT_YES (connection->sk.state.nodelay) ||
       (! plain_send_next))
   {
     if (mhd_connection_set_nodelay_state (connection, true))
@@ -672,9 +672,9 @@ post_send_setopt (struct MHD_Connection *connection,
 #  else  /* ! mhd_CORK_RESET_PUSH_DATA_ALWAYS */
   /* This is old FreeBSD or Darwin kernel. */
 
-  if (mhd_T_IS_NO (connection->sk_corked))
+  if (mhd_T_IS_NO (connection->sk.state.corked))
   {
-    mhd_assert (mhd_T_IS_NOT_YES (connection->sk_nodelay));
+    mhd_assert (mhd_T_IS_NOT_YES (connection->sk.state.nodelay));
 
     /* Unlikely to reach this code.
      * TCP_NODELAY should be turned on before send(). */
@@ -692,7 +692,7 @@ post_send_setopt (struct MHD_Connection *connection,
   else
   {
 #ifdef mhd_CORK_RESET_PUSH_DATA
-    enum mhd_Tristate old_cork_state = connection->sk_corked;
+    enum mhd_Tristate old_cork_state = connection->sk.state.corked;
 #endif /* mhd_CORK_RESET_PUSH_DATA */
     /* The socket is corked or cork state is unknown. */
 
@@ -707,7 +707,7 @@ post_send_setopt (struct MHD_Connection *connection,
       /* Unlikely to reach this code.
        * The data should be pushed by uncorking (FreeBSD) or
        * the socket should be uncorked before send(). */
-      if (mhd_T_IS_YES (connection->sk_nodelay) ||
+      if (mhd_T_IS_YES (connection->sk.state.nodelay) ||
           (mhd_connection_set_nodelay_state (connection, true)))
       {
         /* TCP_NODELAY is turned ON on uncorked socket.
@@ -722,8 +722,8 @@ post_send_setopt (struct MHD_Connection *connection,
 #else  /* ! mhd_TCP_CORK_NOPUSH */
   /* Corking is not supported. Buffering is controlled
    * by TCP_NODELAY only. */
-  mhd_assert (mhd_T_IS_NOT_YES (connection->sk_corked));
-  if (mhd_T_IS_YES (connection->sk_nodelay))
+  mhd_assert (mhd_T_IS_NOT_YES (connection->sk.state.corked));
+  if (mhd_T_IS_YES (connection->sk.state.nodelay))
     return; /* Data was already pushed by send(). */
 
   /* Unlikely to reach this code.
@@ -768,12 +768,12 @@ mhd_plain_send (struct MHD_Connection *restrict c,
 
   pre_send_setopt (c, true, push_data);
 #ifdef mhd_USE_MSG_MORE
-  res = mhd_sys_send4 (c->socket_fd,
+  res = mhd_sys_send4 (c->sk.fd,
                        buf,
                        buf_size,
                        push_data ? 0 : MSG_MORE);
 #else
-  res = mhd_sys_send4 (c->socket_fd,
+  res = mhd_sys_send4 (c->sk.fd,
                        buf,
                        buf_size,
                        0);
@@ -786,8 +786,8 @@ mhd_plain_send (struct MHD_Connection *restrict c,
     err = mhd_socket_error_get_from_sys_err (mhd_SCKT_GET_LERR ());
 
     if (mhd_SOCKET_ERR_AGAIN == err)
-      c->sk_ready = (enum mhd_SocketNetState) /* Clear 'send-ready' */
-                    (((unsigned int) c->sk_ready)
+      c->sk.ready = (enum mhd_SocketNetState) /* Clear 'send-ready' */
+                    (((unsigned int) c->sk.ready)
                      & (~(enum mhd_SocketNetState)
                         mhd_SOCKET_NET_STATE_SEND_READY));
 
@@ -798,8 +798,8 @@ mhd_plain_send (struct MHD_Connection *restrict c,
   full_buf_sent = (buf_size == (size_t) res);
 
   if (! full_buf_sent)
-    c->sk_ready = (enum mhd_SocketNetState) /* Clear 'send-ready' */
-                  (((unsigned int) c->sk_ready)
+    c->sk.ready = (enum mhd_SocketNetState) /* Clear 'send-ready' */
+                  (((unsigned int) c->sk.ready)
                    & (~(enum mhd_SocketNetState)
                       mhd_SOCKET_NET_STATE_SEND_READY));
 
@@ -826,7 +826,7 @@ mhd_send_data (struct MHD_Connection *restrict connection,
 {
   const bool tls_conn = false; // TODO: TLS support
 
-  mhd_assert (MHD_INVALID_SOCKET != connection->socket_fd);
+  mhd_assert (MHD_INVALID_SOCKET != connection->sk.fd);
   mhd_assert (MHD_CONNECTION_CLOSED != connection->state);
 
   if (tls_conn)
@@ -869,7 +869,7 @@ mhd_send_hdr_and_body (struct MHD_Connection *restrict connection,
   bool send_error;
   bool push_hdr;
   bool push_body;
-  MHD_Socket s = connection->socket_fd;
+  MHD_Socket s = connection->sk.fd;
 #ifdef mhd_USE_VECT_SEND
 #if defined(HAVE_SENDMSG) || defined(HAVE_WRITEV)
   struct iovec vector[2];
@@ -891,7 +891,7 @@ mhd_send_hdr_and_body (struct MHD_Connection *restrict connection,
   defined(mhd_SEND_SPIPE_SUPPRESS_POSSIBLE) && \
   defined(mhd_SEND_SPIPE_SUPPRESS_NEEDED)
   no_vec = no_vec || (! connection->daemon->sigpipe_blocked &&
-                      ! connection->sk_spipe_suppress);
+                      ! connection->sk.props.has_spipe_supp);
 #endif /* (!HAVE_SENDMSG || ! MSG_NOSIGNAL) &&
           mhd_SEND_SPIPE_SUPPRESS_POSSIBLE &&
           mhd_SEND_SPIPE_SUPPRESS_NEEDED */
@@ -951,7 +951,7 @@ mhd_send_hdr_and_body (struct MHD_Connection *restrict connection,
         (header_size == *sent) &&
         (0 != body_size) &&
         (header_size < header_size + body_size) &&
-        (connection->sk_nonblck))
+        (connection->sk.props.is_nonblck))
     {
       size_t sent_b;
       /* The header has been sent completely.
@@ -1053,16 +1053,16 @@ mhd_send_hdr_and_body (struct MHD_Connection *restrict connection,
     err = mhd_socket_error_get_from_sys_err (mhd_SCKT_GET_LERR ());
 
     if (mhd_SOCKET_ERR_AGAIN == err)
-      connection->sk_ready = (enum mhd_SocketNetState) /* Clear 'send-ready' */
-                             (((unsigned int) connection->sk_ready)
+      connection->sk.ready = (enum mhd_SocketNetState) /* Clear 'send-ready' */
+                             (((unsigned int) connection->sk.ready)
                               & (~(enum mhd_SocketNetState)
                                  mhd_SOCKET_NET_STATE_SEND_READY));
 
     return err;
   }
   if ((header_size + body_size) > *sent)
-    connection->sk_ready = (enum mhd_SocketNetState) /* Clear 'send-ready' */
-                           (((unsigned int) connection->sk_ready)
+    connection->sk.ready = (enum mhd_SocketNetState) /* Clear 'send-ready' */
+                           (((unsigned int) connection->sk.ready)
                             & (~(enum mhd_SocketNetState)
                                mhd_SOCKET_NET_STATE_SEND_READY));
 
@@ -1178,12 +1178,12 @@ mhd_send_sendfile (struct MHD_Connection *restrict c,
   {
     ssize_t res;
 #ifndef HAVE_SENDFILE64
-    ret = sendfile (c->socket_fd,
+    ret = sendfile (c->sk.fd,
                     file_fd,
                     &offset,
                     send_size);
 #else  /* HAVE_SENDFILE64 */
-    res = sendfile64 (c->socket_fd,
+    res = sendfile64 (c->sk.fd,
                       file_fd,
                       &offset,
                       send_size);
@@ -1219,7 +1219,7 @@ mhd_send_sendfile (struct MHD_Connection *restrict c,
             freebsd_sendfile_flags_thd_p_c_ : freebsd_sendfile_flags_;
 #endif /* SF_FLAGS */
     if (0 != sendfile (file_fd,
-                       c->socket_fd,
+                       c->sk.fd,
                        offset,
                        send_size,
                        NULL,
@@ -1263,7 +1263,7 @@ mhd_send_sendfile (struct MHD_Connection *restrict c,
     len = (off_t) send_size; /* chunk always fit */
 
     if (0 != sendfile (file_fd,
-                       c->socket_fd,
+                       c->sk.fd,
                        offset,
                        &len,
                        NULL,
@@ -1312,8 +1312,8 @@ mhd_send_sendfile (struct MHD_Connection *restrict c,
 
   if ((mhd_SOCKET_ERR_AGAIN == ret) ||
       ((mhd_SOCKET_ERR_NO_ERROR == ret) && (send_size > sent_bytes)))
-    c->sk_ready = (enum mhd_SocketNetState) /* Clear 'send-ready' */
-                  (((unsigned int) c->sk_ready)
+    c->sk.ready = (enum mhd_SocketNetState) /* Clear 'send-ready' */
+                  (((unsigned int) c->sk.ready)
                    & (~(enum mhd_SocketNetState)
                       mhd_SOCKET_NET_STATE_SEND_READY));
 
@@ -1374,7 +1374,7 @@ send_iov_nontls (struct MHD_Connection *restrict connection,
 
   // TODO: assert for non-TLS
 
-  mhd_assert (MHD_INVALID_SOCKET != connection->socket_fd);
+  mhd_assert (MHD_INVALID_SOCKET != connection->sk.fd);
   mhd_assert (MHD_CONNECTION_CLOSED != connection->state);
 
   send_error = false;
@@ -1400,7 +1400,7 @@ send_iov_nontls (struct MHD_Connection *restrict connection,
   msg.msg_flags = 0;
 
   pre_send_setopt (connection, true, push_data);
-  res = sendmsg (connection->socket_fd, &msg,
+  res = sendmsg (connection->sk.fd, &msg,
                  mhd_MSG_NOSIGNAL | (push_data ? 0 : mhd_MSG_MORE));
   if (0 < res)
     *sent = (size_t) res;
@@ -1408,7 +1408,7 @@ send_iov_nontls (struct MHD_Connection *restrict connection,
     send_error = true;
 #elif defined(HAVE_WRITEV)
   pre_send_setopt (connection, false, push_data);
-  res = writev (connection->socket_fd, r_iov->iov + r_iov->sent,
+  res = writev (connection->sk.fd, r_iov->iov + r_iov->sent,
                 items_to_send);
   if (0 < res)
     *sent = (size_t) res;
@@ -1427,7 +1427,7 @@ send_iov_nontls (struct MHD_Connection *restrict connection,
   cnt_w = (DWORD) items_to_send;
 #endif /* ! _WIN64 */
   pre_send_setopt (connection, true, push_data);
-  if (0 == WSASend (connection->socket_fd,
+  if (0 == WSASend (connection->sk.fd,
                     (LPWSABUF) (r_iov->iov + r_iov->sent),
                     cnt_w,
                     &bytes_sent, 0, NULL, NULL))
@@ -1445,8 +1445,8 @@ send_iov_nontls (struct MHD_Connection *restrict connection,
     err = mhd_socket_error_get_from_sys_err (mhd_SCKT_GET_LERR ());
 
     if (mhd_SOCKET_ERR_AGAIN == err)
-      connection->sk_ready = (enum mhd_SocketNetState) /* Clear 'send-ready' */
-                             (((unsigned int) connection->sk_ready)
+      connection->sk.ready = (enum mhd_SocketNetState) /* Clear 'send-ready' */
+                             (((unsigned int) connection->sk.ready)
                               & (~(enum mhd_SocketNetState)
                                  mhd_SOCKET_NET_STATE_SEND_READY));
 
@@ -1470,8 +1470,8 @@ send_iov_nontls (struct MHD_Connection *restrict connection,
       post_send_setopt (connection, true, push_data);
     else
     {
-      connection->sk_ready = (enum mhd_SocketNetState) /* Clear 'send-ready' */
-                             (((unsigned int) connection->sk_ready)
+      connection->sk.ready = (enum mhd_SocketNetState) /* Clear 'send-ready' */
+                             (((unsigned int) connection->sk.ready)
                               & (~(enum mhd_SocketNetState)
                                  mhd_SOCKET_NET_STATE_SEND_READY));
       if (0 != track_sent)
@@ -1518,7 +1518,7 @@ send_iov_emu (struct MHD_Connection *restrict connection,
               bool push_data,
               size_t *restrict sent)
 {
-  const bool non_blk = connection->sk_nonblck;
+  const bool non_blk = connection->sk.props.is_nonblck;
   size_t total_sent;
   size_t max_elelements_to_sent;
 
@@ -1603,7 +1603,7 @@ mhd_send_iovec (struct MHD_Connection *restrict connection,
 #endif /* HTTPS_SUPPORT */
 #ifdef mhd_VECT_SEND_NEEDS_SPIPE_SUPPRESSED
   use_iov_send = use_iov_send && (connection->daemon->sigpipe_blocked ||
-                                  connection->sk_spipe_suppress);
+                                  connection->sk.props.has_spipe_supp);
 #endif /* mhd_VECT_SEND_NEEDS_SPIPE_SUPPRESSED */
   if (use_iov_send)
 #endif /* HTTPS_SUPPORT || mhd_VECT_SEND_NEEDS_SPIPE_SUPPRESSED */
diff --git a/src/mhd2/mhd_send.h b/src/mhd2/mhd_send.h
index 0d2e2c37..8000c063 100644
--- a/src/mhd2/mhd_send.h
+++ b/src/mhd2/mhd_send.h
@@ -144,7 +144,7 @@ MHD_FN_PAR_NONNULL_ALL_ MHD_FN_PAR_OUT_ (4);
 /**
  * Set required TCP_NODELAY state for connection socket
  *
- * The function automatically updates sk_nodelay state.
+ * The function automatically updates sk.nodelay state.
  * @param connection the connection to manipulate
  * @param nodelay_state the requested new state of socket
  * @return true if succeed, false if failed or not supported
@@ -159,7 +159,7 @@ MHD_FN_PAR_NONNULL_ALL_;
 /**
  * Set required cork state for connection socket
  *
- * The function automatically updates sk_corked state.
+ * The function automatically updates sk.corked state.
  *
  * @param connection the connection to manipulate
  * @param cork_state the requested new state of socket
diff --git a/src/mhd2/stream_funcs.c b/src/mhd2/stream_funcs.c
index 65a7b836..28fee317 100644
--- a/src/mhd2/stream_funcs.c
+++ b/src/mhd2/stream_funcs.c
@@ -726,7 +726,7 @@ mhd_conn_start_closing (struct MHD_Connection *restrict c,
     break;
   case mhd_CONN_CLOSE_SOCKET_ERR:
     close_hard = true;
-    switch (c->sk_discnt_err)
+    switch (c->sk.state.discnt_err)
     {
     case mhd_SOCKET_ERR_NOMEM:
       end_code = MHD_REQUEST_ENDED_NO_RESOURCES;
@@ -816,13 +816,13 @@ mhd_conn_start_closing (struct MHD_Connection *restrict c,
   if (close_hard)
   {
     /* Use abortive closing, send RST to remote to indicate a problem */
-    (void) mhd_socket_set_hard_close (c->socket_fd);
+    (void) mhd_socket_set_hard_close (c->sk.fd);
     c->state = MHD_CONNECTION_PRE_CLOSING;
     c->event_loop_info = MHD_EVENT_LOOP_INFO_CLEANUP;
   }
   else
   {
-    if (mhd_socket_shut_wr (c->socket_fd) && (! c->sk_rmt_shut_wr))
+    if (mhd_socket_shut_wr (c->sk.fd) && (! c->sk.state.rmt_shut_wr))
     {
       (void) 0; // TODO: start local lingering phase
       c->state = MHD_CONNECTION_PRE_CLOSING; // TODO: start local lingering phase
@@ -893,7 +893,7 @@ mhd_conn_pre_clean_part1 (struct MHD_Connection *restrict c)
     event.data.ptr = NULL;
     if (0 != epoll_ctl (c->daemon->events.data.epoll.e_fd,
                         EPOLL_CTL_DEL,
-                        c->socket_fd,
+                        c->sk.fd,
                         &event))
     {
       mhd_LOG_MSG (c->daemon, MHD_SC_EPOLL_CTL_REMOVE_FAILED,
diff --git a/src/mhd2/stream_process_reply.c b/src/mhd2/stream_process_reply.c
index 6138ba50..685d1805 100644
--- a/src/mhd2/stream_process_reply.c
+++ b/src/mhd2/stream_process_reply.c
@@ -136,7 +136,7 @@ get_conn_reuse (struct MHD_Connection *c)
     return mhd_CONN_MUST_CLOSE;
 
   mhd_assert ( (! c->stop_with_error) || (c->discard_request));
-  if ((c->sk_rmt_shut_wr) || (c->discard_request))
+  if ((c->sk.state.rmt_shut_wr) || (c->discard_request))
     return mhd_CONN_MUST_CLOSE;
 
   if (rp->cfg.close_forced)
diff --git a/src/mhd2/stream_process_states.c b/src/mhd2/stream_process_states.c
index 600b8494..84856930 100644
--- a/src/mhd2/stream_process_states.c
+++ b/src/mhd2/stream_process_states.c
@@ -66,7 +66,7 @@ update_active_state (struct MHD_Connection *restrict c)
   /* Do not update states of suspended connection */
   mhd_assert (! c->suspended);
 
-  if (0 != (c->sk_ready & mhd_SOCKET_NET_STATE_ERROR_READY))
+  if (0 != (c->sk.ready & mhd_SOCKET_NET_STATE_ERROR_READY))
   {
     mhd_assert (0 && "Should be handled earlier");
     mhd_conn_start_closing_skt_err (c);
@@ -208,10 +208,10 @@ update_active_state (struct MHD_Connection *restrict c)
   mhd_assert (MHD_EVENT_LOOP_INFO_PROCESS != c->event_loop_info);
 
   /* Sockets errors must be already handled */
-  mhd_assert (0 == (c->sk_ready & mhd_SOCKET_NET_STATE_ERROR_READY));
+  mhd_assert (0 == (c->sk.ready & mhd_SOCKET_NET_STATE_ERROR_READY));
 
   if (0 !=
-      (((unsigned int) c->sk_ready) & ((unsigned int) c->event_loop_info)
+      (((unsigned int) c->sk.ready) & ((unsigned int) c->event_loop_info)
        & (MHD_EVENT_LOOP_INFO_RECV | MHD_EVENT_LOOP_INFO_SEND)))
     mhd_conn_mark_ready (c, c->daemon);
   else
@@ -230,7 +230,7 @@ mhd_conn_process_data (struct MHD_Connection *restrict c)
   /* 'daemon' is not used if epoll is not available and asserts are disabled */
   (void) d; /* Mute compiler warning */
 
-  if ((c->sk_rmt_shut_wr) && (MHD_CONNECTION_START_REPLY > c->state))
+  if ((c->sk.state.rmt_shut_wr) && (MHD_CONNECTION_START_REPLY > c->state))
   {
     if (0 == c->read_buffer_offset)
     { /* Read buffer is empty, connection state is actual */
@@ -251,14 +251,14 @@ mhd_conn_process_data (struct MHD_Connection *restrict c)
     (void) 0;
   }
 
-  if ((mhd_SOCKET_ERR_NO_ERROR != c->sk_discnt_err) ||
-      (0 != (c->sk_ready & mhd_SOCKET_NET_STATE_ERROR_READY)))
+  if ((mhd_SOCKET_ERR_NO_ERROR != c->sk.state.discnt_err) ||
+      (0 != (c->sk.ready & mhd_SOCKET_NET_STATE_ERROR_READY)))
   {
-    mhd_assert ((mhd_SOCKET_ERR_NO_ERROR == c->sk_discnt_err) || \
-                mhd_SOCKET_ERR_IS_HARD (c->sk_discnt_err));
-    if ((mhd_SOCKET_ERR_NO_ERROR == c->sk_discnt_err) ||
-        (mhd_SOCKET_ERR_NOT_CHECKED == c->sk_discnt_err))
-      c->sk_discnt_err = mhd_socket_error_get_from_socket (c->socket_fd);
+    mhd_assert ((mhd_SOCKET_ERR_NO_ERROR == c->sk.state.discnt_err) || \
+                mhd_SOCKET_ERR_IS_HARD (c->sk.state.discnt_err));
+    if ((mhd_SOCKET_ERR_NO_ERROR == c->sk.state.discnt_err) ||
+        (mhd_SOCKET_ERR_NOT_CHECKED == c->sk.state.discnt_err))
+      c->sk.state.discnt_err = mhd_socket_error_get_from_socket (c->sk.fd);
     mhd_conn_start_closing_skt_err (c);
     return false;
   }
@@ -459,7 +459,7 @@ mhd_conn_process_data (struct MHD_Connection *restrict c)
         c,
         mhd_CONN_KEEPALIVE_POSSIBLE == c->conn_reuse
         && ! c->discard_request
-        && ! c->sk_rmt_shut_wr);
+        && ! c->sk.state.rmt_shut_wr);
       continue;
 #ifdef MHD_UPGRADE_SUPPORT
     case MHD_CONNECTION_UPGRADING:
@@ -506,7 +506,7 @@ mhd_conn_process_data (struct MHD_Connection *restrict c)
     return true;
   }
 
-  if ((c->sk_rmt_shut_wr) && (MHD_CONNECTION_START_REPLY > c->state))
+  if ((c->sk.state.rmt_shut_wr) && (MHD_CONNECTION_START_REPLY > c->state))
   {
     mhd_conn_start_closing (c,
                             (MHD_CONNECTION_INIT == c->state) ?
diff --git a/src/mhd2/upgraded_net.c b/src/mhd2/upgraded_net.c
index b331c0aa..cd7b3c14 100644
--- a/src/mhd2/upgraded_net.c
+++ b/src/mhd2/upgraded_net.c
@@ -110,7 +110,7 @@ MHD_upgraded_recv (struct MHD_UpgradedHandle *MHD_RESTRICT urh,
 {
   struct MHD_Connection *restrict c = urh->c;
 #if defined(MHD_USE_POLL) || defined(MHD_USE_SELECT)
-  const MHD_Socket socket_fd = c->socket_fd;
+  const MHD_Socket socket_fd = c->sk.fd;
 #endif /* MHD_USE_POLL || MHD_USE_SELECT */
   char *restrict buf_char = (char *) recv_buf;
   size_t last_block_size;
@@ -167,7 +167,7 @@ MHD_upgraded_recv (struct MHD_UpgradedHandle *MHD_RESTRICT urh,
   if (mhd_SOCKET_ERR_NO_ERROR == res)
   {
     if (0 == last_block_size)
-      c->sk_rmt_shut_wr = true;
+      c->sk.state.rmt_shut_wr = true;
     *received_size += last_block_size;
     return MHD_SC_OK;
   }
@@ -220,7 +220,7 @@ MHD_upgraded_recv (struct MHD_UpgradedHandle *MHD_RESTRICT urh,
 #  if defined(MHD_USE_SELECT)
       bool use_select;
 #    ifdef MHD_SOCKETS_KIND_POSIX
-      use_select = (socket_fd < FD_SETSIZE);
+      use_select = (sk.fd < FD_SETSIZE);
 #    else  /* MHD_SOCKETS_KIND_WINSOCK */
       use_select = true;
 #    endif /* MHD_SOCKETS_KIND_WINSOCK */
@@ -245,9 +245,9 @@ MHD_upgraded_recv (struct MHD_UpgradedHandle *MHD_RESTRICT urh,
         else
           tmvl.tv_usec = (int) (max_wait_millisec % 1000);
         FD_ZERO (&rfds);
-        FD_SET (socket_fd, &rfds);
+        FD_SET (sk.fd, &rfds);
 
-        sel_res = select (c->socket_fd + 1,
+        sel_res = select (c->sk.fd + 1,
                           &rfds,
                           NULL,
                           NULL,
@@ -295,7 +295,7 @@ MHD_upgraded_recv (struct MHD_UpgradedHandle *MHD_RESTRICT urh,
       if (mhd_SOCKET_ERR_NO_ERROR == res)
       {
         if (0 == last_block_size)
-          c->sk_rmt_shut_wr = true;
+          c->sk.state.rmt_shut_wr = true;
         *received_size += last_block_size;
         return MHD_SC_OK;
       }
@@ -327,7 +327,7 @@ MHD_upgraded_send (struct MHD_UpgradedHandle *MHD_RESTRICT urh,
 {
   struct MHD_Connection *restrict c = urh->c;
 #if defined(MHD_USE_POLL) || defined(MHD_USE_SELECT)
-  const MHD_Socket socket_fd = c->socket_fd;
+  const MHD_Socket socket_fd = c->sk.fd;
 #endif /* MHD_USE_POLL || MHD_USE_SELECT */
   const char *restrict buf_char = (const char *) send_buf;
   const bool push_data = (MHD_NO == more_data_to_come);
@@ -452,7 +452,7 @@ MHD_upgraded_send (struct MHD_UpgradedHandle *MHD_RESTRICT urh,
 #else /* ! MHD_USE_POLL */
 #  if defined(MHD_USE_SELECT)
 #    ifdef MHD_SOCKETS_KIND_POSIX
-    use_select = (socket_fd < FD_SETSIZE);
+    use_select = (sk.fd < FD_SETSIZE);
 #    else  /* MHD_SOCKETS_KIND_WINSOCK */
     use_select = true;
 #    endif /* MHD_SOCKETS_KIND_WINSOCK */
@@ -488,9 +488,9 @@ MHD_upgraded_send (struct MHD_UpgradedHandle *MHD_RESTRICT urh,
           tmvl.tv_usec = (int) (max_wait_millisec % 1000);
       }
       FD_ZERO (&wfds);
-      FD_SET (socket_fd, &wfds);
+      FD_SET (sk.fd, &wfds);
 
-      sel_res = select (c->socket_fd + 1,
+      sel_res = select (c->sk.fd + 1,
                         NULL,
                         &wfds,
                         NULL,