diff --git a/rfc/0004_ws2p_v1.md b/rfc/0004_ws2p_v1.md
index 7bf802d25c6e1368aa359e7028ccc02d2de561e7..d530d005a1b38cfae1cbfb0bf39bf02a6cbf3be4 100644
--- a/rfc/0004_ws2p_v1.md
+++ b/rfc/0004_ws2p_v1.md
@@ -249,8 +249,8 @@ Accepted since duniter-ts **v1.6.0**
     
 #### message field
 
-API = "WS2P"  
-MESSAGE_TYPE = "HEAD"  
+API = `WS2P`  
+MESSAGE_TYPE = `HEAD`  
 PUBKEY := public key of the issuer node of this head  
 BLOCKSTAMP = `blockNumber-Hash`
 
@@ -263,7 +263,7 @@ sig: ed25519 signature of the message field in base64.
 Accepted since duniter-ts **v1.6.9**
 
     {
-        "message": String("API:MESSAGE_TYPE:1:PUBKEY:BLOCKSTAMP:WS2PID:SOFTWARE:SOFT_VERSION:POW_PREFIX"),
+        "message": String("API:MESSAGE_TYPE:HEAD_VERSION:PUBKEY:BLOCKSTAMP:WS2PID:SOFTWARE:SOFT_VERSION:POW_PREFIX"),
         "sig": String("MY90zXICfbYhLlz8VrL4HWPkphZEFR+bT2JWsoKdDMadgn0R0ZjsowDsnlfNqX4F4qeWeFoxhvdVgTO9VSghCA==")
     }
     
@@ -271,6 +271,7 @@ Accepted since duniter-ts **v1.6.9**
 
 API = `WS2P`  
 MESSAGE_TYPE = `HEAD`  
+HEAD_VERSION = 1  
 PUBKEY := public key of the issuer node of this head  
 BLOCKSTAMP = `blockNumber-Hash`  
 WS2PID := unique identifier of the ws2p endpoint  
@@ -288,17 +289,18 @@ Accepted since duniter-ts **v1.6.9**, relayed fully since duniter-ts **v1.6.15**
 _Nodes with versions lower than 1.6.15 bounce a degraded version of the head, only `message` and `sig` fields are relayed._
 
     {
-        "message": String("API:HEAD:1:PUBKEY:BLOCKSTAMP:WS2PID:SOFTWARE:SOFT_VERSION:POW_PREFIX"),
+        "message": String("API:HEAD:HEAD_VERSION:PUBKEY:BLOCKSTAMP:WS2PID:SOFTWARE:SOFT_VERSION:POW_PREFIX"),
         "sig": String("TPh2A3NS8cHj8yrJk1Yeldx2H6bPEp46cFAGZXKfxJcNgXL2sWrlirhIOlp8pkUFSrwDawWY1zO1jlgUqMvlAg=="),
-        "messageV2": String("API:HEAD:2:PUBKEY:BLOCKSTAMP:WS2PID:SOFTWARE:SOFT_VERSION:POW_PREFIX:FREE_MEMBER_ROOM:FREE_MIRROR_ROOM"),
+        "messageV2": String("API:HEAD:HEAD_VERSION:PUBKEY:BLOCKSTAMP:WS2PID:SOFTWARE:SOFT_VERSION:POW_PREFIX:FREE_MEMBER_ROOM:FREE_MIRROR_ROOM"),
         "sigV2": String("ta1lRrWsjGcYHcLdS75JgEW5B8ByRetFVUVVpakKNJBirhRe8HcYUHEOM7xj/+gUQGGOit6Gm5Q/lsvfsngWAQ=="),
         "step": Number(0)
     }
     
 #### message & messageV2 fields
 
-API := field indicating the network layer type and giving some information about the Network configuration. (See section "API field" for details)
+API := field indicating the network layer type and giving some information about the Network configuration. (See section "API field" for details)  
 MESSAGE_TYPE = `HEAD`  
+HEAD_VERSION = 2  
 PUBKEY := public key of the issuer node of this head  
 BLOCKSTAMP = `blockNumber-Hash`  
 WS2PID := unique identifier of the ws2p endpoint