I want to write a client program that communicates with the application server via standard TCP/IP. The client can speak to the application server and be authenticated by simply speaking in a specific text based protocol. The traffic will be encrypted, but there won’t be username/password. If another application tries to communicate with the application server and if the application doesn’t use the correct text based protocol, the application server will silently discard packets.
Waiting for suggestions.
You can use a simplified version of TLV (Tag Length Value).
The basic idea is to define a set of message types which are represented by a code of fixed size (the T for Tag). Depending the type of message the contents of it (the V for Value) can very so you specify its length (the L for Length) before the contents. The Length field also has fixed size
Suppose you have one message used to send user data to the server. You can define a message like:
Edited:
I was about to forget: Merry Christmas 🙂