diff --git a/src/rtp/rtcp.h b/src/rtp/rtcp.h
new file mode 100644
index 0000000..3c22c24
--- /dev/null
+++ b/src/rtp/rtcp.h
@@ -0,0 +1,120 @@
+/**
+ * @file rtcp.h  Internal interface to RTCP
+ *
+ * Copyright (C) 2010 Creytiv.com
+ */
+
+
+/** RTCP protocol values */
+enum {
+	RTCP_HDR_SIZE  =   4,  /**< Size of common RTCP header   */
+	RTCP_SRC_SIZE  =   4,  /**< Size of Source field         */
+	RTCP_SR_SIZE   =  20,  /**< Size of Sender Information   */
+	RTCP_RR_SIZE   =  24,  /**< Size of Report Block         */
+	RTCP_APP_SIZE  =   8,  /**< Size of Application packet   */
+	RTCP_FIR_SIZE  =   4,  /**< Size of FIR packet           */
+	RTCP_NACK_SIZE =   8,  /**< Size of NACK packet          */
+	RTCP_FB_SIZE   =   8,  /**< Size of Feedback packets     */
+	RTCP_MAX_SDES  = 255,  /**< Maximum text length for SDES */
+	RTCP_HEADROOM  =   4,  /**< Headroom in RTCP packets     */
+};
+
+/** NTP Time */
+struct ntp_time {
+	uint32_t hi;  /**< Seconds since 0h UTC on 1 January 1900 */
+	uint32_t lo;  /**< Fraction of seconds                    */
+};
+
+struct hash;
+
+/** Per-source state information */
+struct rtp_source {
+	struct sa rtp_peer;       /**< IP-address of the RTP source        */
+	uint16_t max_seq;         /**< Highest seq. number seen            */
+	uint32_t cycles;          /**< Shifted count of seq. number cycles */
+	uint32_t base_seq;        /**< Base seq number                     */
+	uint32_t bad_seq;         /**< Last 'bad' seq number + 1           */
+	uint32_t probation;       /**< Sequ. packets till source is valid  */
+	uint32_t received;        /**< Packets received                    */
+	uint32_t expected_prior;  /**< Packet expected at last interval    */
+	uint32_t received_prior;  /**< Packet received at last interval    */
+	int transit;              /**< Relative trans time for prev pkt    */
+	uint32_t jitter;          /**< Estimated jitter                    */
+	size_t rtp_rx_bytes;      /**< Number of RTP bytes received        */
+	uint64_t sr_recv;         /**< When the last SR was received       */
+	struct ntp_time last_sr;  /**< NTP Timestamp from last SR received */
+	uint32_t rtp_ts;          /**< RTP timestamp                       */
+	uint32_t psent;           /**< RTP packets sent                    */
+	uint32_t osent;           /**< RTP octets sent                     */
+};
+
+/** RTP Member */
+struct rtp_member {
+	struct le le;             /**< Hash-table element                  */
+	struct rtp_source *s;     /**< RTP source state                    */
+	uint32_t src;             /**< Source - used for hash-table lookup */
+	int cum_lost;             /**< Cumulative number of packets lost   */
+	uint32_t jit;             /**< Jitter in [us]                      */
+	uint32_t rtt;             /**< Round-trip time in [us]             */
+};
+
+
+/* Member */
+struct rtp_member *member_add(struct hash *ht, uint32_t src);
+struct rtp_member *member_find(struct hash *ht, uint32_t src);
+
+/* Source */
+void source_init_seq(struct rtp_source *s, uint16_t seq);
+int  source_update_seq(struct rtp_source *s, uint16_t seq);
+void source_calc_jitter(struct rtp_source *s, uint32_t rtp_ts,
+			uint32_t arrival);
+int  source_calc_lost(const struct rtp_source *s);
+uint8_t source_calc_fraction_lost(struct rtp_source *s);
+
+/* RR (Reception report) */
+int rtcp_rr_alloc(struct rtcp_rr **rrp, size_t count);
+int rtcp_rr_encode(struct mbuf *mb, const struct rtcp_rr *rr);
+int rtcp_rr_decode(struct mbuf *mb, struct rtcp_rr *rr);
+
+/* SDES (Source Description) */
+int rtcp_sdes_decode(struct mbuf *mb, struct rtcp_sdes *sdes);
+
+/* RTCP Feedback */
+int rtcp_rtpfb_gnack_encode(struct mbuf *mb, uint16_t pid, uint16_t blp);
+int rtcp_psfb_sli_encode(struct mbuf *mb, uint16_t first, uint16_t number,
+			 uint8_t picid);
+int rtcp_rtpfb_decode(struct mbuf *mb, struct rtcp_msg *msg);
+int rtcp_psfb_decode(struct mbuf *mb, struct rtcp_msg *msg);
+
+/** NTP Time */
+struct timeval;
+void unix2ntp(struct ntp_time *ntp, const struct timeval *tv);
+void ntp2unix(struct timeval *tv, const struct ntp_time *ntp);
+int  ntp_time_get(struct ntp_time *ntp);
+uint32_t ntp_compact(const struct ntp_time *ntp);
+uint64_t ntp_compact2us(uint32_t ntpc);
+
+/* RTP Socket */
+struct rtcp_sess *rtp_rtcp_sess(const struct rtp_sock *rs);
+
+/* RTCP message */
+typedef int (rtcp_encode_h)(struct mbuf *mb, void *arg);
+
+int rtcp_hdr_encode(struct mbuf *mb, uint8_t count, enum rtcp_type type,
+		    uint16_t length);
+int rtcp_hdr_decode(struct mbuf *mb, struct rtcp_hdr *hdr);
+int rtcp_vencode(struct mbuf *mb, enum rtcp_type type, uint32_t count,
+		 va_list ap);
+
+/* RTCP Session */
+struct rtcp_sess;
+
+int  rtcp_sess_alloc(struct rtcp_sess **sessp, struct rtp_sock *rs);
+int  rtcp_enable(struct rtcp_sess *sess, bool enabled, const char *cname);
+int  rtcp_send(struct rtp_sock *rs, struct mbuf *mb);
+void rtcp_handler(struct rtcp_sess *sess, struct rtcp_msg *msg);
+void rtcp_sess_tx_rtp(struct rtcp_sess *sess, uint32_t ts,
+		      size_t payload_size);
+void rtcp_sess_rx_rtp(struct rtcp_sess *sess, uint16_t seq, uint32_t ts,
+		      uint32_t src, size_t payload_size,
+		      const struct sa *peer);