Overview

Most packets roughly follow the format below:

(command):(destination):(source):(data)\r\n

command

The name of the command. See each section for the commands.

Each command is prefixed with one of the following:

Symbol Details
$ Requests and responses
# Adding/removing clients, text messages
% ATC update
@ Aircraft update

destination

The destination of the packet. This may be any one of the following. Case does not seem to matter:

  • DATA
  • SERVER
  • FP
  • The callsign of an online station / aircraft

The first three appear to be VATSIM-specific.

source

The sender of the packet. See destination for valid formats.

data

The content of the packet. See the following sections for valid formats.