diff --git a/src/tlv.hpp b/src/tlv.hpp
new file mode 100644
index 0000000..b793c01
--- /dev/null
+++ b/src/tlv.hpp
@@ -0,0 +1,40 @@
+#ifndef CHRONOCHAT_TLV_HPP
+#define CHRONOCHAT_TLV_HPP
+
+namespace chronochat {
+
+namespace tlv {
+
+enum {
+  ChatroomInfo = 128,
+  ChatroomName = 129,
+  TrustModel = 130,
+  ChatroomPrefix = 131,
+  ManagerPrefix = 132,
+  Participants = 133,
+  Conf = 134,
+  Nick = 135,
+  Profile = 136,
+  ProfileEntry = 137,
+  Oid = 138,
+  EntryData = 139,
+  EndorseExtension = 140,
+  EndorseCollection = 141,
+  EndorseCollectionEntry = 142,
+  Hash = 143,
+  EndorseInfo = 144,
+  Endorsement = 145,
+  EndorseType = 146,
+  EndorseValue = 147,
+  EndorseCount = 148,
+  ChatMessage = 149,
+  ChatMessageType = 150,
+  ChatData = 151,
+  Timestamp = 152,
+};
+
+} // namespace tlv
+
+} // namespace chronochat
+
+#endif // CHRONOCHAT_TLV_HPP