diff --git a/ngc_ext_common.hpp b/ngc_ext_common.hpp
index a5fd94c..910cbc6 100644
--- a/ngc_ext_common.hpp
+++ b/ngc_ext_common.hpp
@@ -85,16 +85,66 @@ enum _PacketType : uint8_t {
 	// - ]
 	HS1_RESPONSE_LAST_IDS,
 
+	// request the other side to initiate a FT
+	// - 1 byte (file_kind)
+	// - X bytes (file_kind dependent id, differnt sizes)
+	FT1_REQUEST,
+
+	// tell the other side you want to start a FT
+	// TODO: might use id layer instead. with it, it would look similar to friends_ft
+	// - 1 byte (file_kind)
+	// - X bytes (file_kind dependent id, differnt sizes)
+	// - 8 bytes (data size) // TODO: do all file kinds have a size at init?
+	// - 1 byte (temporary_file_tf_id, for this peer only, technically just a prefix to distinguish between simultainious fts)
+	FT1_INIT,
+
+	// acknowlage init (like an accept)
+	// - 1 byte (temporary_file_tf_id)
+	FT1_INIT_ACK,
+
+	// data fragment
+	// - 1 byte (temporary_file_tf_id)
+	// - 2 bytes (sequece id)
+	// - X bytes (the data fragment)
+	// (size is implicit)
+	FT1_DATA,
+
+	// acknowlage data fragments
+	// TODO: last 3 should be sufficient, 5 should be generous, would eleminate the byte for size
+	// - 1 byte (temporary_file_tf_id)
+	// - 1 byte (number of sequence ids to ack, this kind of depends on window size)
+	// - array [ (of sequece ids)
+	//   - 2 bytes (sequece id)
+	// - ]
+	FT1_DATA_ACK,
+
+	// sender has gotten every data fragment acked, so we signal finish
+	// - 1 byte (temporary_file_tf_id)
+	FT1_DATA_FIN,
+
+	// and we ack that, we need this, so file_id is not reused earlier
+	// - 1 byte (temporary_file_tf_id)
+	FT1_DATA_FIN_ACK,
 };
 
 static const char* _pkgid2str(_PacketType type) {
-#define _HS1_CASE(x) case (x): return #x;
+#define _EXT_CASE(x) case (x): return #x;
 	switch (type) {
-		_HS1_CASE(INVALID)
-		_HS1_CASE(HS1_REQUEST_LAST_IDS)
-		_HS1_CASE(HS1_RESPONSE_LAST_IDS)
+		_EXT_CASE(INVALID)
+
+		_EXT_CASE(HS1_REQUEST_LAST_IDS)
+		_EXT_CASE(HS1_RESPONSE_LAST_IDS)
+
+		_EXT_CASE(FT1_REQUEST)
+		_EXT_CASE(FT1_INIT)
+		_EXT_CASE(FT1_INIT_ACK)
+		_EXT_CASE(FT1_DATA)
+		_EXT_CASE(FT1_DATA_ACK)
+		_EXT_CASE(FT1_DATA_FIN)
+		_EXT_CASE(FT1_DATA_FIN_ACK)
+
 		default: return "<unk>";
 	}
-#undef _HS1_CASE
+#undef _EXT_CASE
 }