diff --git a/docs/protocol-v0.md b/docs/protocol-v0.md
index 19c259b..1f0cef5 100644
--- a/docs/protocol-v0.md
+++ b/docs/protocol-v0.md
@@ -98,6 +98,8 @@ partner IPv6 and partner port may be nullbytes (no partner included).
 A block request is sent from node A to node B in order to transfer a block from node B to node A.  
 Node B should answer with a "block transfer" message that includes the requested block (as given by "block hash")
 
+If "block hash" consists of 32 nullbytes, node A wants node B to send the newest block of B's blockchain.
+
 ### block transfer
 
 | content | size (bytes) |
@@ -127,3 +129,22 @@ A "block transfer" message is sent back in response to a "block request" message
 | type = 4 (BE) | 1 |
 | list position (0 <= x < 1024) (BE) | 2 |
 | "open transaction" hash value | 32 |
+
+### open transaction request
+
+| content | size (bytes) |
+|---|---|
+| protocol version = 0 (BE) | 2 |
+| capable version = 0 (BE) | 2 |
+| type = 5 (BE) | 1 |
+| list position (0 <= x < 1024) (BE) | 2 |
+
+### open transaction response
+
+| content | size (bytes) |
+|---|---|
+| protocol version = 0 (BE) | 2 |
+| capable version = 0 (BE) | 2 |
+| type = 4 (BE) | 1 |
+| list position (0 <= x < 1024) (BE) | 2 |
+| transaction | 148 |