diff --git a/include/net/tcp.h b/include/net/tcp.h
index c29d4ce..14aee64 100644
--- a/include/net/tcp.h
+++ b/include/net/tcp.h
@@ -277,9 +277,40 @@
 	TCP_FIN_WAIT_2
 };
 
-enum tcp_state tcp_get_tcp_state(void);
-void tcp_set_tcp_state(enum tcp_state new_state);
-int tcp_set_tcp_header(uchar *pkt, int dport, int sport, int payload_len,
+/**
+ * struct tcp_stream - TCP data stream structure
+ *
+ * @state:		TCP connection state
+ *
+ * @seq_init:		Initial receive sequence number
+ * @ack_edge:		Receive next
+ *
+ * @loc_timestamp:	Local timestamp
+ * @rmt_timestamp:	Remote timestamp
+ *
+ * @lost:		Used for SACK
+ */
+struct tcp_stream {
+	/* TCP connection state */
+	enum tcp_state	state;
+
+	u32		seq_init;
+	u32		ack_edge;
+
+	/* TCP option timestamp */
+	u32		loc_timestamp;
+	u32		rmt_timestamp;
+
+	/* TCP sliding window control used to request re-TX */
+	struct tcp_sack_v lost;
+};
+
+struct tcp_stream *tcp_stream_get(void);
+
+enum tcp_state tcp_get_tcp_state(struct tcp_stream *tcp);
+void tcp_set_tcp_state(struct tcp_stream *tcp, enum tcp_state new_state);
+int tcp_set_tcp_header(struct tcp_stream *tcp, uchar *pkt, int dport,
+		       int sport, int payload_len,
 		       u8 action, u32 tcp_seq_num, u32 tcp_ack_num);
 
 /**