Protocol

Window Switch uses a very simple line based message exchange for all communications between client and server.
This makes it very easy to observe with the usual set of network packet capture tools, the clients and the server also support regular expressions which will log any messages (sent or received) that match it: simply start with the option --trace-protocol-message=RE
It also makes it possible to access it using telnet or netcat.
The sockets used for communication can be automatically discovered using mDNS.

Here are the message formats and their purpose:

Message Type	Message Parameters	Purpose	From Server	From Client
ping	none	test the connection
OK	none	Sent in response to ping
NOK	none	Sent if any error occurred or the command was not recognised
help	none	display help message
User Commands
add_user	username, password, uuid, etc	Login to the server or add a user to the client
remove_user	uuid	Remove user (no longer available)
logout	none	Logout
authentication_failed	message	Tell the client that login failed
authentication_success	message	Tell the client that login succeeded
send_message	uuid, message	Send a message to another user
request_user_icon	uuid	Request the user's avatar icon
set_user_icon	uuid, icon data	Send the user's avatar icon
Session Commands
add_session	ID, name, command, display, status...	Add a session to the client's list
start_session	command, name, session type...	Start a new session on the server
shadow_session	display, read_only	Start a shadow session of an existing session
open_file	filename	Open a file on the server
remove_session	ID	Removes a session from the client's list
send_session	ID, user, [password]	Send a session to a user
request_session	ID	Request access to the session
kill_session	ID	Force the session to terminate
close_session	ID	Close the session
set_session_status	ID, status, actor	Modify the session's state
request_session_icon	ID	Request the session's icon
set_session_icon	ID, icon data	Set the session's icon
Menu Commands
add_server_command	ID, command, name	Add a command to the menu list
request_command_icon	ID	Request the commmand's icon
set_command_icon	ID, icon data	Send the commmand's icon
System Messages
sync	none	Request synchronisation of data
sync_end	none	Sent after all the data
version	version number	Information about the software version
set_salt	salt	Sets the salt which must be used for signing/authentication
set_remote_key	key, signature, signed salt, etc	The client or server's credentials
set_host_info	name, type, etc	Supplemental information about the host
set_tunnel_ports	list of ports	Ports that the client must use for tunnelling
set_xmodmap	xmodmap	The keyboard mappings for this user