diff --git a/include/mbedtls/ssl.h b/include/mbedtls/ssl.h
index c754b9bb2..abe7d2844 100644
--- a/include/mbedtls/ssl.h
+++ b/include/mbedtls/ssl.h
@@ -445,7 +445,7 @@ struct mbedtls_ssl_session
 #endif
     int ciphersuite;            /*!< chosen ciphersuite */
     int compression;            /*!< chosen compression */
-    size_t length;              /*!< session id length  */
+    size_t id_len;              /*!< session id length  */
     unsigned char id[32];       /*!< session identifier */
     unsigned char master[48];   /*!< the master secret  */
 
diff --git a/library/ssl_cache.c b/library/ssl_cache.c
index e05bd8831..162b47a44 100644
--- a/library/ssl_cache.c
+++ b/library/ssl_cache.c
@@ -86,11 +86,11 @@ int mbedtls_ssl_cache_get( void *data, mbedtls_ssl_session *session )
 
         if( session->ciphersuite != entry->session.ciphersuite ||
             session->compression != entry->session.compression ||
-            session->length != entry->session.length )
+            session->id_len != entry->session.id_len )
             continue;
 
         if( memcmp( session->id, entry->session.id,
-                    entry->session.length ) != 0 )
+                    entry->session.id_len ) != 0 )
             continue;
 
         memcpy( session->master, entry->session.master, 48 );
@@ -167,7 +167,7 @@ int mbedtls_ssl_cache_set( void *data, const mbedtls_ssl_session *session )
         }
 #endif
 
-        if( memcmp( session->id, cur->session.id, cur->session.length ) == 0 )
+        if( memcmp( session->id, cur->session.id, cur->session.id_len ) == 0 )
             break; /* client reconnected, keep timestamp for session id */
 
 #if defined(MBEDTLS_HAVE_TIME)
diff --git a/library/ssl_cli.c b/library/ssl_cli.c
index e2c2d3fa9..58ca440f4 100644
--- a/library/ssl_cli.c
+++ b/library/ssl_cli.c
@@ -587,7 +587,7 @@ static int ssl_write_client_hello( mbedtls_ssl_context *ssl )
      *   ..   . ..    extensions length (2 bytes)
      *   ..   . ..    extensions
      */
-    n = ssl->session_negotiate->length;
+    n = ssl->session_negotiate->id_len;
 
     if( n < 16 || n > 32 ||
 #if defined(MBEDTLS_SSL_RENEGOTIATION)
@@ -615,7 +615,7 @@ static int ssl_write_client_hello( mbedtls_ssl_context *ssl )
             if( ret != 0 )
                 return( ret );
 
-            ssl->session_negotiate->length = n = 32;
+            ssl->session_negotiate->id_len = n = 32;
         }
     }
 #endif /* MBEDTLS_SSL_SESSION_TICKETS */
@@ -1345,7 +1345,7 @@ static int ssl_parse_server_hello( mbedtls_ssl_context *ssl )
 #endif
         ssl->session_negotiate->ciphersuite != i ||
         ssl->session_negotiate->compression != comp ||
-        ssl->session_negotiate->length != n ||
+        ssl->session_negotiate->id_len != n ||
         memcmp( ssl->session_negotiate->id, buf + 35, n ) != 0 )
     {
         ssl->state++;
@@ -1355,7 +1355,7 @@ static int ssl_parse_server_hello( mbedtls_ssl_context *ssl )
 #endif
         ssl->session_negotiate->ciphersuite = i;
         ssl->session_negotiate->compression = comp;
-        ssl->session_negotiate->length = n;
+        ssl->session_negotiate->id_len = n;
         memcpy( ssl->session_negotiate->id, buf + 35, n );
     }
     else
@@ -2902,7 +2902,7 @@ static int ssl_parse_new_session_ticket( mbedtls_ssl_context *ssl )
      * discards any Session ID that was sent in the ServerHello."
      */
     MBEDTLS_SSL_DEBUG_MSG( 3, ( "ticket in use, discarding session id" ) );
-    ssl->session_negotiate->length = 0;
+    ssl->session_negotiate->id_len = 0;
 
     MBEDTLS_SSL_DEBUG_MSG( 2, ( "<= parse new session ticket" ) );
 
diff --git a/library/ssl_srv.c b/library/ssl_srv.c
index 457362f96..f09c9168b 100644
--- a/library/ssl_srv.c
+++ b/library/ssl_srv.c
@@ -454,8 +454,8 @@ static int ssl_parse_session_ticket_ext( mbedtls_ssl_context *ssl,
      * Keep the session ID sent by the client, since we MUST send it back to
      * inform them we're accepting the ticket  (RFC 5077 section 3.4)
      */
-    session.length = ssl->session_negotiate->length;
-    memcpy( &session.id, ssl->session_negotiate->id, session.length );
+    session.id_len = ssl->session_negotiate->id_len;
+    memcpy( &session.id, ssl->session_negotiate->id, session.id_len );
 
     mbedtls_ssl_session_free( ssl->session_negotiate );
     memcpy( ssl->session_negotiate, &session, sizeof( mbedtls_ssl_session ) );
@@ -888,10 +888,10 @@ static int ssl_parse_client_hello_v2( mbedtls_ssl_context *ssl )
                    buf + 6 + ciph_len + sess_len, chal_len );
 
     p = buf + 6 + ciph_len;
-    ssl->session_negotiate->length = sess_len;
+    ssl->session_negotiate->id_len = sess_len;
     memset( ssl->session_negotiate->id, 0,
             sizeof( ssl->session_negotiate->id ) );
-    memcpy( ssl->session_negotiate->id, p, ssl->session_negotiate->length );
+    memcpy( ssl->session_negotiate->id, p, ssl->session_negotiate->id_len );
 
     p += sess_len;
     memset( ssl->handshake->randbytes, 0, 64 );
@@ -1338,11 +1338,11 @@ read_record_header:
 
     MBEDTLS_SSL_DEBUG_BUF( 3, "client hello, session id", buf + 35, sess_len );
 
-    ssl->session_negotiate->length = sess_len;
+    ssl->session_negotiate->id_len = sess_len;
     memset( ssl->session_negotiate->id, 0,
             sizeof( ssl->session_negotiate->id ) );
     memcpy( ssl->session_negotiate->id, buf + 35,
-            ssl->session_negotiate->length );
+            ssl->session_negotiate->id_len );
 
     /*
      * Check the cookie length and content
@@ -2180,7 +2180,7 @@ static int ssl_write_server_hello( mbedtls_ssl_context *ssl )
 #if defined(MBEDTLS_SSL_RENEGOTIATION)
         ssl->renego_status == MBEDTLS_SSL_INITIAL_HANDSHAKE &&
 #endif
-        ssl->session_negotiate->length != 0 &&
+        ssl->session_negotiate->id_len != 0 &&
         ssl->conf->f_get_cache != NULL &&
         ssl->conf->f_get_cache( ssl->conf->p_cache, ssl->session_negotiate ) == 0 )
     {
@@ -2203,13 +2203,13 @@ static int ssl_write_server_hello( mbedtls_ssl_context *ssl )
 #if defined(MBEDTLS_SSL_SESSION_TICKETS)
         if( ssl->handshake->new_session_ticket != 0 )
         {
-            ssl->session_negotiate->length = n = 0;
+            ssl->session_negotiate->id_len = n = 0;
             memset( ssl->session_negotiate->id, 0, 32 );
         }
         else
 #endif /* MBEDTLS_SSL_SESSION_TICKETS */
         {
-            ssl->session_negotiate->length = n = 32;
+            ssl->session_negotiate->id_len = n = 32;
             if( ( ret = ssl->conf->f_rng( ssl->conf->p_rng, ssl->session_negotiate->id,
                                     n ) ) != 0 )
                 return( ret );
@@ -2220,7 +2220,7 @@ static int ssl_write_server_hello( mbedtls_ssl_context *ssl )
         /*
          * Resuming a session
          */
-        n = ssl->session_negotiate->length;
+        n = ssl->session_negotiate->id_len;
         ssl->state = MBEDTLS_SSL_SERVER_CHANGE_CIPHER_SPEC;
 
         if( ( ret = mbedtls_ssl_derive_keys( ssl ) ) != 0 )
@@ -2238,9 +2238,9 @@ static int ssl_write_server_hello( mbedtls_ssl_context *ssl )
      *   42+n . 43+n    extensions length
      *   44+n . 43+n+m  extensions
      */
-    *p++ = (unsigned char) ssl->session_negotiate->length;
-    memcpy( p, ssl->session_negotiate->id, ssl->session_negotiate->length );
-    p += ssl->session_negotiate->length;
+    *p++ = (unsigned char) ssl->session_negotiate->id_len;
+    memcpy( p, ssl->session_negotiate->id, ssl->session_negotiate->id_len );
+    p += ssl->session_negotiate->id_len;
 
     MBEDTLS_SSL_DEBUG_MSG( 3, ( "server hello, session id len.: %d", n ) );
     MBEDTLS_SSL_DEBUG_BUF( 3,   "server hello, session id", buf + 39, n );
diff --git a/library/ssl_tls.c b/library/ssl_tls.c
index f14c9dde0..bbec08a9c 100644
--- a/library/ssl_tls.c
+++ b/library/ssl_tls.c
@@ -4610,7 +4610,7 @@ void mbedtls_ssl_handshake_wrapup( mbedtls_ssl_context *ssl )
      * Add cache entry
      */
     if( ssl->conf->f_set_cache != NULL &&
-        ssl->session->length != 0 &&
+        ssl->session->id_len != 0 &&
         resume == 0 )
     {
         if( ssl->conf->f_set_cache( ssl->conf->p_cache, ssl->session ) != 0 )