[docs] Update protocol docsv0.2.0

1 files changed, 29 insertions, 19 deletions

diff --git a/docs/rfc.md b/docs/rfc.md
index 8296cfa..854d737 100644
--- a/docs/rfc.md
+++ b/docs/rfc.md
@@ -180,7 +180,6 @@ Payload is always empty for this type.
 |------|-----------------------------------------------------------|
 | 0x01 | Client auth failed. Invalid username or password.         |
 | 0x02 | Not found. User or channel cannot access user or channel. |
-| 0x03 | Server auth failed. Unknown name.                        |
 
 ### Handshake
 
@@ -246,7 +245,7 @@ Some operations require multiple rounds of communication.
 In this case payloads are send in a sequence. Payload that is not part of this
 specific operation (for example incoming message) cannot interrupt this process.
 
-### Client-Server connection initialisation
+## Client-Server connection initialisation
 
 ~~~ ascii-art
 +--------+                   +--------+
@@ -259,20 +258,40 @@ specific operation (for example incoming message) cannot interrupt this process.
      | Send [Handshake]           |
      +--------------------------->|
      |                            |
-     |                            +- If [ver_major] does not match server
-     |                            |  protocol version close the connection
+     |                            +- If [ver_major] does not match
+     |                            |  server protocol version close
+     |                            |  the connection.
      |                            |
-     | Send [UserAuth]          |
+     | Send [UserAuth]            |
      +--------------------------->|
      |                            |
      | Send [Error 0x01]          |
-     |<---------------------------+- If [username] or [password] does not match
-     |                            |  and close the connection
+     |<---------------------------+- If [username] or [password]
+     |                            |  does not match and close
+     |                            |  the connection.
      |                            |
      | Send [Sucesss]             |
      |<---------------------------+
 ~~~
 
+## Exchanging messages between servers
+
+Exchanging messages between SOLEC servers is a core concept behind the project.
+Sending message to user residing on a different server require estabilishing a
+connection between both servers.
+
+
+### Authentication
+
+Server authentication is crucial to prevent message spoofing and other forms of
+abuse. Server cannot use same auth process as clients because that would require
+creating account for each server on any other server which is impossible.
+Possible solution are TLS or other public key based protocol.
+
+As for now the issue remains open and server authorization uses mock
+[ServerAuth] payload which specifies just the connecting server name.
+This is obviously insecure.
+
 ### Server-Server connection initialisation
 
 ~~~ ascii-art
@@ -286,22 +305,13 @@ specific operation (for example incoming message) cannot interrupt this process.
      | Send [Handshake]           |
      +--------------------------->|
      |                            |
-     |                            +- If [ver_major] does not match server
-     |                            |  protocol version close the connection
+     |                            +- If [ver_major] does not match
+     |                            |  server protocol version close
+     |                            |  the connection.
      |                            |
      | Send [ServerAuth]          |
      +--------------------------->|
      |                            |
-     | Send [Error 0x03]          |
-     |<---------------------------+- If [name] is not present in known public
-     |                            |  keys list.
-     |                            |
      | Send [Sucesss]             |
      |<---------------------------+
 ~~~
-
-## Server to server operation
-
-Exchanging messages between SOLEC servers is a core concept behind the project.
-Sending message to user residing on a different server require estabilishing a
-connection between both servers.