diff --git a/configs/baremetal.h b/configs/baremetal.h
index 43a488c2f..038b06026 100644
--- a/configs/baremetal.h
+++ b/configs/baremetal.h
@@ -165,7 +165,7 @@
 #define MBEDTLS_SSL_KEEP_PEER_CERTIFICATE
 #define MBEDTLS_DELAYED_SERVER_CERT_VERIFICATION
 #define MBEDTLS_SSL_FREE_SERVER_CERTIFICATE
-#define MBEDTLS_IMMEDIATE_TRANSMISSION
+#define MBEDTLS_SSL_IMMEDIATE_TRANSMISSION
 #define MBEDTLS_EARLY_KEY_COMPUTATION
 
 #if defined(MBEDTLS_USER_CONFIG_FILE)
diff --git a/include/mbedtls/config.h b/include/mbedtls/config.h
index 3c3c1ce56..0fca50a89 100644
--- a/include/mbedtls/config.h
+++ b/include/mbedtls/config.h
@@ -1616,13 +1616,13 @@
 
 
 /**
- * \def MBEDTLS_IMMEDIATE_TRANSMISSION
+ * \def MBEDTLS_SSL_IMMEDIATE_TRANSMISSION
  *
  * Force stack to immediately transmit messages.
  *
  * Requires: MBEDTLS_SSL_PROTO_DTLS
  */
-//#define MBEDTLS_IMMEDIATE_TRANSMISSION
+//#define MBEDTLS_SSL_IMMEDIATE_TRANSMISSION
 
 /**
  * \def MBEDTLS_EARLY_KEY_COMPUTATION
diff --git a/include/mbedtls/ssl_internal.h b/include/mbedtls/ssl_internal.h
index 80da3ac1a..bd2169ef3 100644
--- a/include/mbedtls/ssl_internal.h
+++ b/include/mbedtls/ssl_internal.h
@@ -1203,7 +1203,7 @@ void mbedtls_ssl_send_flight_completed( mbedtls_ssl_context *ssl );
 void mbedtls_ssl_recv_flight_completed( mbedtls_ssl_context *ssl );
 int mbedtls_ssl_resend( mbedtls_ssl_context *ssl );
 int mbedtls_ssl_flight_transmit( mbedtls_ssl_context *ssl );
-#if defined(MBEDTLS_IMMEDIATE_TRANSMISSION)
+#if defined(MBEDTLS_SSL_IMMEDIATE_TRANSMISSION)
 void mbedtls_ssl_immediate_flight_done( mbedtls_ssl_context *ssl );
 #endif
 #endif
diff --git a/library/ssl_cli.c b/library/ssl_cli.c
index eba30fa72..bde7d10ff 100644
--- a/library/ssl_cli.c
+++ b/library/ssl_cli.c
@@ -1143,7 +1143,7 @@ static int ssl_write_client_hello( mbedtls_ssl_context *ssl )
 #if defined(MBEDTLS_SSL_PROTO_DTLS)
     if( MBEDTLS_SSL_TRANSPORT_IS_DTLS( ssl->conf->transport ) )
     {
-#if defined(MBEDTLS_IMMEDIATE_TRANSMISSION)
+#if defined(MBEDTLS_SSL_IMMEDIATE_TRANSMISSION)
         mbedtls_ssl_immediate_flight_done( ssl );
 #else
         if( ( ret = mbedtls_ssl_flight_transmit( ssl ) ) != 0 )
diff --git a/library/ssl_srv.c b/library/ssl_srv.c
index ce92f98dc..7ef263c49 100644
--- a/library/ssl_srv.c
+++ b/library/ssl_srv.c
@@ -2745,7 +2745,7 @@ static int ssl_write_hello_verify_request( mbedtls_ssl_context *ssl )
 #if defined(MBEDTLS_SSL_PROTO_DTLS)
     if( MBEDTLS_SSL_TRANSPORT_IS_DTLS( ssl->conf->transport ) )
     {
-#if defined(MBEDTLS_IMMEDIATE_TRANSMISSION)
+#if defined(MBEDTLS_SSL_IMMEDIATE_TRANSMISSION)
         mbedtls_ssl_immediate_flight_done( ssl );
 #else
         if( ( ret = mbedtls_ssl_flight_transmit( ssl ) ) != 0 )
@@ -3810,7 +3810,7 @@ static int ssl_write_server_hello_done( mbedtls_ssl_context *ssl )
 #if defined(MBEDTLS_SSL_PROTO_DTLS)
     if( MBEDTLS_SSL_TRANSPORT_IS_DTLS( ssl->conf->transport ) )
     {
-#if defined(MBEDTLS_IMMEDIATE_TRANSMISSION)
+#if defined(MBEDTLS_SSL_IMMEDIATE_TRANSMISSION)
         mbedtls_ssl_immediate_flight_done( ssl );
 #else
         if( ( ret = mbedtls_ssl_flight_transmit( ssl ) ) != 0 )
diff --git a/library/ssl_tls.c b/library/ssl_tls.c
index b1205a4dc..75ec82170 100644
--- a/library/ssl_tls.c
+++ b/library/ssl_tls.c
@@ -4527,7 +4527,7 @@ static int ssl_flight_append( mbedtls_ssl_context *ssl )
         cur->next = msg;
     }
 
-#if defined(MBEDTLS_IMMEDIATE_TRANSMISSION)
+#if defined(MBEDTLS_SSL_IMMEDIATE_TRANSMISSION)
     ssl->handshake->cur_msg = msg;
     ssl->handshake->cur_msg_p = msg->p + 12;
     {
@@ -4634,7 +4634,7 @@ int mbedtls_ssl_resend( mbedtls_ssl_context *ssl )
     return( ret );
 }
 
-#if defined(MBEDTLS_IMMEDIATE_TRANSMISSION)
+#if defined(MBEDTLS_SSL_IMMEDIATE_TRANSMISSION)
 void mbedtls_ssl_immediate_flight_done( mbedtls_ssl_context *ssl )
 {
     MBEDTLS_SSL_DEBUG_MSG( 2, ( "=> mbedtls_ssl_immediate_flight_done" ) );
@@ -8743,7 +8743,7 @@ int mbedtls_ssl_write_finished( mbedtls_ssl_context *ssl )
 #if defined(MBEDTLS_SSL_PROTO_DTLS)
     if( MBEDTLS_SSL_TRANSPORT_IS_DTLS( ssl->conf->transport ) )
     {
-#if defined(MBEDTLS_IMMEDIATE_TRANSMISSION)
+#if defined(MBEDTLS_SSL_IMMEDIATE_TRANSMISSION)
         mbedtls_ssl_immediate_flight_done( ssl );
 #else
         if( ( ret = mbedtls_ssl_flight_transmit( ssl ) ) != 0 )
diff --git a/library/version_features.c b/library/version_features.c
index 26bade403..11045f8bc 100644
--- a/library/version_features.c
+++ b/library/version_features.c
@@ -495,9 +495,9 @@ static const char *features[] = {
 #if defined(MBEDTLS_SSL_FREE_SERVER_CERTIFICATE)
     "MBEDTLS_SSL_FREE_SERVER_CERTIFICATE",
 #endif /* MBEDTLS_SSL_FREE_SERVER_CERTIFICATE */
-#if defined(MBEDTLS_IMMEDIATE_TRANSMISSION)
-    "MBEDTLS_IMMEDIATE_TRANSMISSION",
-#endif /* MBEDTLS_IMMEDIATE_TRANSMISSION */
+#if defined(MBEDTLS_SSL_IMMEDIATE_TRANSMISSION)
+    "MBEDTLS_SSL_IMMEDIATE_TRANSMISSION",
+#endif /* MBEDTLS_SSL_IMMEDIATE_TRANSMISSION */
 #if defined(MBEDTLS_EARLY_KEY_COMPUTATION)
     "MBEDTLS_EARLY_KEY_COMPUTATION",
 #endif /* MBEDTLS_EARLY_KEY_COMPUTATION */
diff --git a/programs/ssl/query_config.c b/programs/ssl/query_config.c
index baf513b33..6f4e67fb3 100644
--- a/programs/ssl/query_config.c
+++ b/programs/ssl/query_config.c
@@ -1362,13 +1362,13 @@ int query_config( const char *config )
     }
 #endif /* MBEDTLS_SSL_FREE_SERVER_CERTIFICATE */
 
-#if defined(MBEDTLS_IMMEDIATE_TRANSMISSION)
-    if( strcmp( "MBEDTLS_IMMEDIATE_TRANSMISSION", config ) == 0 )
+#if defined(MBEDTLS_SSL_IMMEDIATE_TRANSMISSION)
+    if( strcmp( "MBEDTLS_SSL_IMMEDIATE_TRANSMISSION", config ) == 0 )
     {
-        MACRO_EXPANSION_TO_STR( MBEDTLS_IMMEDIATE_TRANSMISSION );
+        MACRO_EXPANSION_TO_STR( MBEDTLS_SSL_IMMEDIATE_TRANSMISSION );
         return( 0 );
     }
-#endif /* MBEDTLS_IMMEDIATE_TRANSMISSION */
+#endif /* MBEDTLS_SSL_IMMEDIATE_TRANSMISSION */
 
 #if defined(MBEDTLS_EARLY_KEY_COMPUTATION)
     if( strcmp( "MBEDTLS_EARLY_KEY_COMPUTATION", config ) == 0 )
diff --git a/scripts/config.pl b/scripts/config.pl
index d9aef53db..1fc156cbd 100755
--- a/scripts/config.pl
+++ b/scripts/config.pl
@@ -64,7 +64,7 @@
 #   MBEDTLS_PLATFORM_FAULT_CALLBACKS
 #   MBEDTLS_DELAYED_SERVER_CERT_VERIFICATION
 #   MBEDTLS_SSL_FREE_SERVER_CERTIFICATE
-#   MBEDTLS_IMMEDIATE_TRANSMISSION
+#   MBEDTLS_SSL_IMMEDIATE_TRANSMISSION
 #   MBEDTLS_EARLY_KEY_COMPUTATION
 #   and any symbol beginning _ALT
 #
@@ -156,7 +156,7 @@ MBEDTLS_AES_128_BIT_MASKED
 MBEDTLS_PLATFORM_FAULT_CALLBACKS
 MBEDTLS_DELAYED_SERVER_CERT_VERIFICATION
 MBEDTLS_SSL_FREE_SERVER_CERTIFICATE
-MBEDTLS_IMMEDIATE_TRANSMISSION
+MBEDTLS_SSL_IMMEDIATE_TRANSMISSION
 MBEDTLS_EARLY_KEY_COMPUTATION
 _ALT\s*$
 );
diff --git a/tests/ssl-opt.sh b/tests/ssl-opt.sh
index e452ca3cd..bcefb8e34 100755
--- a/tests/ssl-opt.sh
+++ b/tests/ssl-opt.sh
@@ -1368,7 +1368,7 @@ run_test    "SHA-256 allowed by default in client certificate" \
             0
 
 # Tests for datagram packing
-requires_config_disabled MBEDTLS_IMMEDIATE_TRANSMISSION
+requires_config_disabled MBEDTLS_SSL_IMMEDIATE_TRANSMISSION
 run_test    "DTLS: multiple records in same datagram, client and server" \
             "$P_SRV dtls=1 dgram_packing=1 debug_level=2" \
             "$P_CLI dtls=1 dgram_packing=1 debug_level=2" \
@@ -1376,7 +1376,7 @@ run_test    "DTLS: multiple records in same datagram, client and server" \
             -c "next record in same datagram" \
             -s "next record in same datagram"
 
-requires_config_disabled MBEDTLS_IMMEDIATE_TRANSMISSION
+requires_config_disabled MBEDTLS_SSL_IMMEDIATE_TRANSMISSION
 run_test    "DTLS: multiple records in same datagram, client only" \
             "$P_SRV dtls=1 dgram_packing=0 debug_level=2" \
             "$P_CLI dtls=1 dgram_packing=1 debug_level=2" \
@@ -1384,7 +1384,7 @@ run_test    "DTLS: multiple records in same datagram, client only" \
             -s "next record in same datagram" \
             -C "next record in same datagram"
 
-requires_config_disabled MBEDTLS_IMMEDIATE_TRANSMISSION
+requires_config_disabled MBEDTLS_SSL_IMMEDIATE_TRANSMISSION
 run_test    "DTLS: multiple records in same datagram, server only" \
             "$P_SRV dtls=1 dgram_packing=1 debug_level=2" \
             "$P_CLI dtls=1 dgram_packing=0 debug_level=2" \