diff --git a/components/net/Kconfig b/components/net/Kconfig
index 97e97ca4b7967cac1cb7f935f12c443ebbc8ee16..30f25cda94056817020c6a36e794752e10147993 100644
--- a/components/net/Kconfig
+++ b/components/net/Kconfig
@@ -5,7 +5,6 @@ menu "Socket abstraction layer"
 config RT_USING_SAL
     bool "Enable socket abstraction layer"
     default n
-    select RT_USING_DFS
 
     if RT_USING_SAL
 
@@ -28,14 +27,24 @@ config RT_USING_SAL
 
         config SAL_USING_POSIX
             bool "Enable BSD socket operated by file system API"
+            default y if RT_USING_POSIX
+            default n
+            select RT_USING_DFS
             select RT_USING_LIBC
             select RT_USING_POSIX
-            default n
             help
                 Let BSD socket operated by file system API, such as read/write and involveed in select/poll POSIX APIs.
+                
+        if !SAL_USING_POSIX
+            
+            config SAL_SOCKETS_NUM
+                int "the maximum number of sockets"
+                default 16
+       
+        endif
         
         config SAL_PROTO_FAMILIES_NUM
-            int "the number of protocol family"
+            int "the maximum number of protocol families"
             default 4
 
     endif
diff --git a/components/net/at/at_socket/at_socket.c b/components/net/at/at_socket/at_socket.c
index a95c7aec539f93488688bac9bfcdf26bf3af3d7f..f754ad52a703f113bf3015ee1beaaa3bf6378706 100644
--- a/components/net/at/at_socket/at_socket.c
+++ b/components/net/at/at_socket/at_socket.c
@@ -46,7 +46,7 @@
         ((unsigned char *)&addr)[2], \
         ((unsigned char *)&addr)[3]
 
-#ifdef AT_DEVICE_NOT_SELECTED
+#if !defined(AT_DEVICE_SOCKETS_NUM) || defined(AT_DEVICE_NOT_SELECTED)
 #error The AT socket device is not selected, please select it through the env menuconfig.
 #endif
 
@@ -398,7 +398,7 @@ int at_closesocket(int socket)
 
     if (last_state == AT_SOCKET_CONNECT)
     {
-        if (at_dev_ops->close(socket) != 0)
+        if (at_dev_ops->at_closesocket(socket) != 0)
         {
             LOG_E("AT socket (%d) closesocket failed!", socket);
         }
@@ -424,7 +424,7 @@ int at_shutdown(int socket, int how)
 
     if (sock->state == AT_SOCKET_CONNECT)
     {
-        if (at_dev_ops->close(socket) != 0)
+        if (at_dev_ops->at_closesocket(socket) != 0)
         {
             LOG_E("AT socket (%d) shutdown failed!", socket);
         }
@@ -535,7 +535,7 @@ int at_connect(int socket, const struct sockaddr *name, socklen_t namelen)
     socketaddr_to_ipaddr_port(name, &remote_addr, &remote_port);
     ipaddr_to_ipstr(name, ipstr);
 
-    if (at_dev_ops->connect(socket, ipstr, remote_port, sock->type, RT_TRUE) < 0)
+    if (at_dev_ops->at_connect(socket, ipstr, remote_port, sock->type, RT_TRUE) < 0)
     {
         LOG_E("AT socket(%d) connect failed!", socket);
         result = -1;
@@ -545,8 +545,8 @@ int at_connect(int socket, const struct sockaddr *name, socklen_t namelen)
     sock->state = AT_SOCKET_CONNECT;
 
     /* set AT socket receive data callback function */
-    at_dev_ops->set_event_cb(AT_SOCKET_EVT_RECV, at_recv_notice_cb);
-    at_dev_ops->set_event_cb(AT_SOCKET_EVT_CLOSED, at_closed_notice_cb);
+    at_dev_ops->at_set_event_cb(AT_SOCKET_EVT_RECV, at_recv_notice_cb);
+    at_dev_ops->at_set_event_cb(AT_SOCKET_EVT_CLOSED, at_closed_notice_cb);
 
 __exit:
 
@@ -593,7 +593,7 @@ int at_recvfrom(int socket, void *mem, size_t len, int flags, struct sockaddr *f
         socketaddr_to_ipaddr_port(from, &remote_addr, &remote_port);
         ipaddr_to_ipstr(from, ipstr);
 
-        if (at_dev_ops->connect(socket, ipstr, remote_port, sock->type, RT_TRUE) < 0)
+        if (at_dev_ops->at_connect(socket, ipstr, remote_port, sock->type, RT_TRUE) < 0)
         {
             LOG_E("AT socket UDP connect failed!");
             result = -1;
@@ -719,7 +719,7 @@ int at_sendto(int socket, const void *data, size_t size, int flags, const struct
             goto __exit;
         }
 
-        if ((len = at_dev_ops->send(sock->socket, (const char *) data, size, sock->type)) < 0)
+        if ((len = at_dev_ops->at_send(sock->socket, (const char *) data, size, sock->type)) < 0)
         {
             result = -1;
             goto __exit;
@@ -736,7 +736,7 @@ int at_sendto(int socket, const void *data, size_t size, int flags, const struct
             socketaddr_to_ipaddr_port(to, &remote_addr, &remote_port);
             ipaddr_to_ipstr(to, ipstr);
 
-            if (at_dev_ops->connect(socket, ipstr, remote_port, sock->type, RT_TRUE) < 0)
+            if (at_dev_ops->at_connect(socket, ipstr, remote_port, sock->type, RT_TRUE) < 0)
             {
                 LOG_E("AT socket (%d) UDP connect failed!", socket);
                 result = -1;
@@ -745,7 +745,7 @@ int at_sendto(int socket, const void *data, size_t size, int flags, const struct
             sock->state = AT_SOCKET_CONNECT;
         }
 
-        if ((len = at_dev_ops->send(sock->socket, (char *) data, size, sock->type)) < 0)
+        if ((len = at_dev_ops->at_send(sock->socket, (char *) data, size, sock->type)) < 0)
         {
             result = -1;
             goto __exit;
@@ -940,7 +940,7 @@ struct hostent *at_gethostbyname(const char *name)
 
     if (idx < strlen(name))
     {
-        if (at_dev_ops->domain_resolve(name, ipstr) < 0)
+        if (at_dev_ops->at_domain_resolve(name, ipstr) < 0)
         {
             LOG_E("AT domain (%s) resolve error!", name);
             return RT_NULL;
@@ -1040,7 +1040,7 @@ int at_getaddrinfo(const char *nodename, const char *servname,
 
             if(idx < strlen(nodename))
             {
-                if (at_dev_ops->domain_resolve((char *) nodename, ip_str) != 0)
+                if (at_dev_ops->at_domain_resolve((char *) nodename, ip_str) != 0)
                 {
                     return EAI_FAIL;
                 }
@@ -1129,10 +1129,10 @@ void at_freeaddrinfo(struct addrinfo *ai)
 void at_scoket_device_register(const struct at_device_ops *ops)
 {
     RT_ASSERT(ops);
-    RT_ASSERT(ops->connect);
-    RT_ASSERT(ops->close);
-    RT_ASSERT(ops->send);
-    RT_ASSERT(ops->domain_resolve);
-    RT_ASSERT(ops->set_event_cb);
+    RT_ASSERT(ops->at_connect);
+    RT_ASSERT(ops->at_closesocket);
+    RT_ASSERT(ops->at_send);
+    RT_ASSERT(ops->at_domain_resolve);
+    RT_ASSERT(ops->at_set_event_cb);
     at_dev_ops = (struct at_device_ops *) ops;
 }
diff --git a/components/net/at/at_socket/at_socket.h b/components/net/at/at_socket/at_socket.h
index 7d9ce91f39dee16140f019aed8c48f92852f4303..f6e2a69d5b183c3fafbfa83c51cc3fd948d81b05 100644
--- a/components/net/at/at_socket/at_socket.h
+++ b/components/net/at/at_socket/at_socket.h
@@ -77,11 +77,11 @@ typedef void (* at_socket_callback)(struct at_socket *conn, int event, uint16_t
 /* AT device socket options function */
 struct at_device_ops
 {
-    int (*connect)(int socket, char *ip, int32_t port, enum at_socket_type type, rt_bool_t is_client);
-    int (*close)(int socket);
-    int (*send)(int socket, const char *buff, size_t bfsz, enum at_socket_type type);
-    int (*domain_resolve)(const char *name, char ip[16]);
-    void (*set_event_cb)(at_socket_evt_t event, at_evt_cb_t cb);
+    int (*at_connect)(int socket, char *ip, int32_t port, enum at_socket_type type, rt_bool_t is_client);
+    int (*at_closesocket)(int socket);
+    int (*at_send)(int socket, const char *buff, size_t bfsz, enum at_socket_type type);
+    int (*at_domain_resolve)(const char *name, char ip[16]);
+    void (*at_set_event_cb)(at_socket_evt_t event, at_evt_cb_t cb);
 };
 
 /* AT receive package list structure */
diff --git a/components/net/lwip-2.0.2/SConscript b/components/net/lwip-2.0.2/SConscript
index 0fc63f4b26ce2eb4fd65efc65ae64161a2382446..d99556af90a10e4b0a7009495d79dbde640b4e44 100644
--- a/components/net/lwip-2.0.2/SConscript
+++ b/components/net/lwip-2.0.2/SConscript
@@ -67,7 +67,7 @@ path = [GetCurrentDir() + '/src',
     GetCurrentDir() + '/src/arch/include',
     GetCurrentDir() + '/src/include/netif']
 
-if not GetDepend('RT_USING_POSIX') or not GetDepend('SAL_USING_POSIX'):
+if not GetDepend('RT_USING_SAL'):
     path += [GetCurrentDir() + '/src/include/posix']
 
 if GetDepend(['RT_LWIP_SNMP']):
diff --git a/components/net/sal_socket/SConscript b/components/net/sal_socket/SConscript
index 3dcb5c3fe420f04ef691d0924737fac4ec6e5c17..e9621933592c2a9b94739603948e92cb4731b2eb 100644
--- a/components/net/sal_socket/SConscript
+++ b/components/net/sal_socket/SConscript
@@ -5,10 +5,9 @@ from building import *
 cwd = GetCurrentDir()
 
 src = Glob('src/*.c')
-src += Glob('socket/*.c')
+src += Glob('socket/net_netdb.c')
 
 CPPPATH = [cwd + '/include']
-CPPPATH += [cwd + '/include/dfs_net']
 CPPPATH += [cwd + '/include/socket']
 
 if GetDepend('SAL_USING_LWIP'):
@@ -21,6 +20,8 @@ if GetDepend('SAL_USING_LWIP') or GetDepend('SAL_USING_AT'):
     CPPPATH += [cwd + '/impl']
 
 if GetDepend('SAL_USING_POSIX'):
+    CPPPATH += [cwd + '/include/dfs_net']
+    src += Glob('socket/net_sockets.c')
     src += Glob('dfs_net/*.c')
     
     if not GetDepend('HAVE_SYS_SELECT_H'):
diff --git a/components/net/sal_socket/impl/af_inet_at.c b/components/net/sal_socket/impl/af_inet_at.c
index 3337af419446f8f0aceff27aa39dc5d2969834a3..f921e721eb30b4cf53a083f159c96db82c0c0225 100644
--- a/components/net/sal_socket/impl/af_inet_at.c
+++ b/components/net/sal_socket/impl/af_inet_at.c
@@ -22,6 +22,8 @@
  * 2018-06-06     ChenYong     First version
  */
 
+#include <rtthread.h>
+
 #include <netdb.h>
 #include <sal.h>
 
@@ -91,8 +93,6 @@ static const struct proto_ops at_inet_stream_ops =
 
 #ifdef SAL_USING_POSIX
     at_poll,
-#else
-    NULL,
 #endif /* SAL_USING_POSIX */
 };
 
diff --git a/components/net/sal_socket/impl/af_inet_lwip.c b/components/net/sal_socket/impl/af_inet_lwip.c
index c45e39e39e31d3378aff6b05a047001a57a6e11c..563f8947d0819593d7df84aec90fefed86879872 100644
--- a/components/net/sal_socket/impl/af_inet_lwip.c
+++ b/components/net/sal_socket/impl/af_inet_lwip.c
@@ -44,6 +44,7 @@
 #endif
 #endif
 
+#ifdef SAL_USING_POSIX
 /*
  * Re-define lwip socket
  *
@@ -73,9 +74,7 @@ struct lwip_sock {
     /** counter of how many threads are waiting for this socket using select */
     SELWAIT_T select_waiting;
 
-#ifdef SAL_USING_POSIX
     rt_wqueue_t wait_head;
-#endif
 };
 
 extern struct lwip_sock *lwip_tryget_socket(int s);
@@ -160,14 +159,14 @@ static void event_callback(struct netconn *conn, enum netconn_evt evt, u16_t len
 
     if (event)
     {
-#ifdef SAL_USING_POSIX
         rt_wqueue_wakeup(&sock->wait_head, (void*) event);
-#endif
     }
 }
+#endif /* SAL_USING_POSIX */
 
 static int inet_socket(int domain, int type, int protocol)
 {
+#ifdef SAL_USING_POSIX
     int socket;
 
     socket = lwip_socket(domain, type, protocol);
@@ -178,17 +177,18 @@ static int inet_socket(int domain, int type, int protocol)
         lwsock = lwip_tryget_socket(socket);
         lwsock->conn->callback = event_callback;
 
-#ifdef SAL_USING_POSIX
         rt_wqueue_init(&lwsock->wait_head);
-#endif
-
     }
 
     return socket;
+#else
+    return lwip_socket(domain, type, protocol);
+#endif /* SAL_USING_POSIX */
 }
 
 static int inet_accept(int socket, struct sockaddr *addr, socklen_t *addrlen)
 {
+#ifdef SAL_USING_POSIX
     int new_socket;
 
     new_socket = lwip_accept(socket, addr, addrlen);
@@ -198,12 +198,13 @@ static int inet_accept(int socket, struct sockaddr *addr, socklen_t *addrlen)
 
         lwsock = lwip_tryget_socket(new_socket);
 
-#ifdef SAL_USING_POSIX
         rt_wqueue_init(&lwsock->wait_head);
-#endif
     }
 
     return new_socket;
+#else
+    return lwip_accept(socket, addr, addrlen);
+#endif /* SAL_USING_POSIX */
 }
 
 static int inet_getsockname(int socket, struct sockaddr *name, socklen_t *namelen)
@@ -216,6 +217,7 @@ static int inet_getsockname(int socket, struct sockaddr *name, socklen_t *namele
     return lwip_getsockname(socket, name, namelen);
 }
 
+#ifdef SAL_USING_POSIX
 static int inet_poll(struct dfs_fd *file, struct rt_pollreq *req)
 {
     int mask = 0;
@@ -253,6 +255,7 @@ static int inet_poll(struct dfs_fd *file, struct rt_pollreq *req)
 
     return mask;
 }
+#endif
 
 static const struct proto_ops lwip_inet_stream_ops = {
     inet_socket,
@@ -270,7 +273,9 @@ static const struct proto_ops lwip_inet_stream_ops = {
     lwip_getpeername,
     inet_getsockname,
     lwip_ioctl,
+#ifdef SAL_USING_POSIX
     inet_poll,
+#endif
 };
 
 static int inet_create(struct sal_socket *socket, int type, int protocol)
diff --git a/components/net/sal_socket/include/sal.h b/components/net/sal_socket/include/sal.h
index 62ffaa303efb66888d2d3ff0533dc02ea2c3b74f..480167c91d206ea72d8117c83319f7711961c9a0 100644
--- a/components/net/sal_socket/include/sal.h
+++ b/components/net/sal_socket/include/sal.h
@@ -25,9 +25,12 @@
 #ifndef SAL_H__
 #define SAL_H__
 
-#include <dfs_file.h>
 #include <rtdevice.h>
 
+#ifdef SAL_USING_POSIX
+#include <dfs_file.h>
+#endif
+
 #ifdef __cplusplus
 extern "C" {
 #endif
@@ -40,7 +43,9 @@ typedef uint32_t socklen_t;
 #define SAL_SOCKET_MAGIC               0x5A10
 
 /* The maximum number of sockets structure */
+#ifndef SAL_SOCKETS_NUM
 #define SAL_SOCKETS_NUM                DFS_FD_MAX
+#endif
 
 /* The maximum number of protocol families */
 #ifndef SAL_PROTO_FAMILIES_NUM
@@ -68,7 +73,9 @@ struct proto_ops
     int (*getpeername)(int s, struct sockaddr *name, socklen_t *namelen);
     int (*getsockname)(int s, struct sockaddr *name, socklen_t *namelen);
     int (*ioctlsocket)(int s, long cmd, void *arg);
+#ifdef SAL_USING_POSIX
     int (*poll)       (struct dfs_fd *file, struct rt_pollreq *req);
+#endif
 };
 
 struct sal_socket
diff --git a/components/net/sal_socket/include/socket/sys_socket/sys/socket.h b/components/net/sal_socket/include/socket/sys_socket/sys/socket.h
index 2b0357ff819826a6ff3f6026c312b021ec95561a..ec7f7b87ea4095cae9148d30b54640d058e76943 100644
--- a/components/net/sal_socket/include/socket/sys_socket/sys/socket.h
+++ b/components/net/sal_socket/include/socket/sys_socket/sys/socket.h
@@ -26,19 +26,21 @@
 #ifndef SYS_SOCKET_H_
 #define SYS_SOCKET_H_
 
+#include <rtthread.h>
 #include <sal_socket.h>
 
 #ifdef __cplusplus
 extern "C" {
 #endif
 
+#ifdef SAL_USING_POSIX
 int accept(int s, struct sockaddr *addr, socklen_t *addrlen);
 int bind(int s, const struct sockaddr *name, socklen_t namelen);
 int shutdown(int s, int how);
-int getpeername (int s, struct sockaddr *name, socklen_t *namelen);
-int getsockname (int s, struct sockaddr *name, socklen_t *namelen);
-int getsockopt (int s, int level, int optname, void *optval, socklen_t *optlen);
-int setsockopt (int s, int level, int optname, const void *optval, socklen_t optlen);
+int getpeername(int s, struct sockaddr *name, socklen_t *namelen);
+int getsockname(int s, struct sockaddr *name, socklen_t *namelen);
+int getsockopt(int s, int level, int optname, void *optval, socklen_t *optlen);
+int setsockopt(int s, int level, int optname, const void *optval, socklen_t optlen);
 int connect(int s, const struct sockaddr *name, socklen_t namelen);
 int listen(int s, int backlog);
 int recv(int s, void *mem, size_t len, int flags);
@@ -50,6 +52,24 @@ int sendto(int s, const void *dataptr, size_t size, int flags,
 int socket(int domain, int type, int protocol);
 int closesocket(int s);
 int ioctlsocket(int s, long cmd, void *arg);
+#else
+#define accept(s, addr, addrlen)                           sal_accept(s, addr, addrlen)
+#define bind(s, name, namelen)                             sal_bind(s, name, namelen)
+#define shutdown(s, how)                                   sal_shutdown(s, how)
+#define getpeername(s, name, namelen)                      sal_getpeername(s, name, namelen)
+#define getsockname(s, name, namelen)                      sal_getsockname(s, name, namelen)
+#define getsockopt(s, level, optname, optval, optlen)      sal_getsockopt(s, level, optname, optval, optlen)
+#define setsockopt(s, level, optname, optval, optlen)      sal_setsockopt(s, level, optname, optval, optlen)
+#define connect(s, name, namelen)                          sal_connect(s, name, namelen)
+#define listen(s, backlog)                                 sal_listen(s, backlog)
+#define recv(s, mem, len, flags)                           sal_recvfrom(s, mem, len, flags, NULL, NULL)
+#define recvfrom(s, mem, len, flags, from, fromlen)        sal_recvfrom(s, mem, len, flags, from, fromlen)
+#define send(s, dataptr, size, flags)                      sal_sendto(s, dataptr, size, flags, NULL, NULL)
+#define sendto(s, dataptr, size, flags, to, tolen)         sal_sendto(s, dataptr, size, flags, to, tolen)
+#define socket(domain, type, protocol)                     sal_socket(domain, type, protocol)
+#define closesocket(s)                                     sal_closesocket(s)
+#define ioctlsocket(s, cmd, arg)                           sal_ioctlsocket(s, cmd, arg)
+#endif /* SAL_USING_POSIX */
 
 #ifdef __cplusplus
 }
diff --git a/components/net/sal_socket/src/sal_socket.c b/components/net/sal_socket/src/sal_socket.c
index 7b6683a69cd56408d7f2b9761c94572cde5a5b0a..f43492069e0665c3ee3caa3bb8eb5449f3501bd5 100644
--- a/components/net/sal_socket/src/sal_socket.c
+++ b/components/net/sal_socket/src/sal_socket.c
@@ -705,6 +705,7 @@ int sal_ioctlsocket(int socket, long cmd, void *arg)
     return sock->ops->ioctlsocket((int) sock->user_data, cmd, arg);
 }
 
+#ifdef SAL_USING_POSIX
 int sal_poll(struct dfs_fd *file, struct rt_pollreq *req)
 {
     struct sal_socket *sock;
@@ -723,6 +724,7 @@ int sal_poll(struct dfs_fd *file, struct rt_pollreq *req)
 
     return sock->ops->poll(file, req);
 }
+#endif
 
 struct hostent *sal_gethostbyname(const char *name)
 {