diff --git a/include/mbedtls/check_config.h b/include/mbedtls/check_config.h
index 413713c..6895118 100644
--- a/include/mbedtls/check_config.h
+++ b/include/mbedtls/check_config.h
@@ -595,18 +595,18 @@
 #error "MBEDTLS_SSL_DTLS_ANTI_REPLAY  defined, but not all prerequisites"
 #endif
 
-#if defined(MBEDTLS_SSL_CID) &&                              \
+#if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID) &&                              \
     ( !defined(MBEDTLS_SSL_TLS_C) || !defined(MBEDTLS_SSL_PROTO_DTLS) )
-#error "MBEDTLS_SSL_CID  defined, but not all prerequisites"
+#error "MBEDTLS_SSL_DTLS_CONNECTION_ID  defined, but not all prerequisites"
 #endif
 
-#if defined(MBEDTLS_SSL_CID)            &&                 \
+#if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)            &&                 \
     defined(MBEDTLS_SSL_CID_IN_LEN_MAX) &&                 \
     MBEDTLS_SSL_CID_IN_LEN_MAX > 255
 #error "MBEDTLS_SSL_CID_IN_LEN_MAX too large (max 255)"
 #endif
 
-#if defined(MBEDTLS_SSL_CID)            &&                  \
+#if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)            &&                  \
     defined(MBEDTLS_SSL_CID_OUT_LEN_MAX) &&                 \
     MBEDTLS_SSL_CID_OUT_LEN_MAX > 255
 #error "MBEDTLS_SSL_CID_OUT_LEN_MAX too large (max 255)"
diff --git a/include/mbedtls/config.h b/include/mbedtls/config.h
index a7a17aa..b8ec64d 100644
--- a/include/mbedtls/config.h
+++ b/include/mbedtls/config.h
@@ -1270,7 +1270,7 @@
 #define MBEDTLS_SSL_ALL_ALERT_MESSAGES
 
 /**
- * \def MBEDTLS_SSL_CID
+ * \def MBEDTLS_SSL_DTLS_CONNECTION_ID
  *
  * Enable support for the DTLS Connection ID extension
  * (version draft-ietf-tls-dtls-connection-id-05,
@@ -1295,7 +1295,7 @@
  *
  * Uncomment to enable the Connection ID extension.
  */
-#define MBEDTLS_SSL_CID
+#define MBEDTLS_SSL_DTLS_CONNECTION_ID
 
 /**
  * \def MBEDTLS_SSL_ASYNC_PRIVATE
diff --git a/include/mbedtls/ssl.h b/include/mbedtls/ssl.h
index 2896f1d..ad434aa 100644
--- a/include/mbedtls/ssl.h
+++ b/include/mbedtls/ssl.h
@@ -917,9 +917,9 @@
     void *p_export_keys;            /*!< context for key export callback    */
 #endif
 
-#if defined(MBEDTLS_SSL_CID)
+#if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
     size_t cid_len; /*!< The length of CIDs for incoming DTLS records.      */
-#endif /* MBEDTLS_SSL_CID */
+#endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */
 
 #if defined(MBEDTLS_X509_CRT_PARSE_C)
     const mbedtls_x509_crt_profile *cert_profile; /*!< verification profile */
@@ -1045,11 +1045,11 @@
     unsigned int cert_req_ca_list : 1;  /*!< enable sending CA list in
                                           Certificate Request messages?     */
 #endif
-#if defined(MBEDTLS_SSL_CID)
+#if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
     unsigned int ignore_unexpected_cid : 1; /*!< Determines whether DTLS
                                              *   record with unexpected CID
                                              *   should lead to failure.    */
-#endif /* MBEDTLS_SSL_CID */
+#endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */
 };
 
 
@@ -1117,10 +1117,10 @@
                                      TLS: maintained by us
                                      DTLS: read from peer             */
     unsigned char *in_hdr;      /*!< start of record header           */
-#if defined(MBEDTLS_SSL_CID)
+#if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
     unsigned char *in_cid;      /*!< The start of the CID;
                                  *   (the end is marked by in_len).   */
-#endif /* MBEDTLS_SSL_CID */
+#endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */
     unsigned char *in_len;      /*!< two-bytes message length field   */
     unsigned char *in_iv;       /*!< ivlen-byte IV                    */
     unsigned char *in_msg;      /*!< message contents (in_iv+ivlen)   */
@@ -1157,10 +1157,10 @@
     unsigned char *out_buf;     /*!< output buffer                    */
     unsigned char *out_ctr;     /*!< 64-bit outgoing message counter  */
     unsigned char *out_hdr;     /*!< start of record header           */
-#if defined(MBEDTLS_SSL_CID)
+#if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
     unsigned char *out_cid;     /*!< The start of the CID;
                                  *   (the end is marked by in_len).   */
-#endif /* MBEDTLS_SSL_CID */
+#endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */
     unsigned char *out_len;     /*!< two-bytes message length field   */
     unsigned char *out_iv;      /*!< ivlen-byte IV                    */
     unsigned char *out_msg;     /*!< message contents (out_iv+ivlen)  */
@@ -1219,7 +1219,7 @@
     char peer_verify_data[MBEDTLS_SSL_VERIFY_DATA_MAX_LEN]; /*!<  previous handshake verify data */
 #endif /* MBEDTLS_SSL_RENEGOTIATION */
 
-#if defined(MBEDTLS_SSL_CID)
+#if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
     /* CID configuration to use in subsequent handshakes. */
 
     /*! The next incoming CID, chosen by the user and applying to
@@ -1232,7 +1232,7 @@
                             *   be negotiated in the next handshake or not.
                             *   Possible values are #MBEDTLS_SSL_CID_ENABLED
                             *   and #MBEDTLS_SSL_CID_DISABLED. */
-#endif /* MBEDTLS_SSL_CID */
+#endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */
 };
 
 #if defined(MBEDTLS_SSL_HW_RECORD_ACCEL)
@@ -1454,7 +1454,7 @@
 
 #if defined(MBEDTLS_SSL_PROTO_DTLS)
 
-#if defined(MBEDTLS_SSL_CID)
+#if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
 
 
 /**
@@ -1581,7 +1581,7 @@
                      unsigned char peer_cid[ MBEDTLS_SSL_CID_OUT_LEN_MAX ],
                      size_t *peer_cid_len );
 
-#endif /* MBEDTLS_SSL_CID */
+#endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */
 
 /**
  * \brief          Set the Maximum Tranport Unit (MTU).
@@ -2157,7 +2157,7 @@
 void mbedtls_ssl_conf_ciphersuites( mbedtls_ssl_config *conf,
                                    const int *ciphersuites );
 
-#if defined(MBEDTLS_SSL_CID)
+#if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
 #define MBEDTLS_SSL_UNEXPECTED_CID_IGNORE 0
 #define MBEDTLS_SSL_UNEXPECTED_CID_FAIL   1
 /**
@@ -2193,7 +2193,7 @@
  */
 int mbedtls_ssl_conf_cid( mbedtls_ssl_config *conf, size_t len,
                           int ignore_other_cids );
-#endif /* MBEDTLS_SSL_CID */
+#endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */
 
 /**
  * \brief               Set the list of allowed ciphersuites and the
diff --git a/include/mbedtls/ssl_internal.h b/include/mbedtls/ssl_internal.h
index 1561582..e9a80ed 100644
--- a/include/mbedtls/ssl_internal.h
+++ b/include/mbedtls/ssl_internal.h
@@ -166,7 +166,7 @@
 #define MBEDTLS_SSL_PADDING_ADD              0
 #endif
 
-#if defined(MBEDTLS_SSL_CID)
+#if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
 #define MBEDTLS_SSL_MAX_CID_EXPANSION      MBEDTLS_SSL_CID_PADDING_GRANULARITY
 #else
 #define MBEDTLS_SSL_MAX_CID_EXPANSION        0
@@ -229,7 +229,7 @@
    implicit sequence number. */
 #define MBEDTLS_SSL_HEADER_LEN 13
 
-#if defined(MBEDTLS_SSL_CID)
+#if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
 #define MBEDTLS_SSL_IN_BUFFER_LEN  \
     ( ( MBEDTLS_SSL_HEADER_LEN ) + ( MBEDTLS_SSL_IN_PAYLOAD_LEN ) )
 #else
@@ -238,7 +238,7 @@
       + ( MBEDTLS_SSL_CID_IN_LEN_MAX ) )
 #endif
 
-#if defined(MBEDTLS_SSL_CID)
+#if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
 #define MBEDTLS_SSL_OUT_BUFFER_LEN  \
     ( ( MBEDTLS_SSL_HEADER_LEN ) + ( MBEDTLS_SSL_OUT_PAYLOAD_LEN ) )
 #else
@@ -362,7 +362,7 @@
     unsigned char alt_out_ctr[8];       /*!<  Alternative record epoch/counter
                                               for resending messages         */
 
-#if defined(MBEDTLS_SSL_CID)
+#if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
     /* The state of CID configuration in this handshake. */
 
     uint8_t cid_in_use; /*!< This indicates whether the use of the CID extension
@@ -372,7 +372,7 @@
     unsigned char peer_cid[ MBEDTLS_SSL_CID_OUT_LEN_MAX ]; /*! The peer's CID */
     uint8_t peer_cid_len;                                  /*!< The length of
                                                             *   \c peer_cid.  */
-#endif /* MBEDTLS_SSL_CID */
+#endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */
 
     struct
     {
@@ -593,12 +593,12 @@
     mbedtls_cipher_context_t cipher_ctx_dec;    /*!<  decryption context      */
     int minor_ver;
 
-#if defined(MBEDTLS_SSL_CID)
+#if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
     uint8_t in_cid_len;
     uint8_t out_cid_len;
     unsigned char in_cid [ MBEDTLS_SSL_CID_OUT_LEN_MAX ];
     unsigned char out_cid[ MBEDTLS_SSL_CID_OUT_LEN_MAX ];
-#endif /* MBEDTLS_SSL_CID */
+#endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */
 
     /*
      * Session specific compression layer
@@ -646,11 +646,10 @@
     size_t data_offset;     /* Offset of record content */
     size_t data_len;        /* Length of record content */
 
-#if defined(MBEDTLS_SSL_CID)
+#if defined(MBEDTLS_SSL_DTLS_CONNECTION_ID)
     uint8_t cid_len;        /* Length of the CID (0 if not present) */
     unsigned char cid[ MBEDTLS_SSL_CID_LEN_MAX ]; /* The CID        */
-#endif /* MBEDTLS_SSL_CID */
-
+#endif /* MBEDTLS_SSL_DTLS_CONNECTION_ID */
 } mbedtls_record;
 
 #if defined(MBEDTLS_X509_CRT_PARSE_C)