| 12 | | * Ability to show which users are online |
| | 12 | |
| | 13 | We expect to need the ability to... |
| | 14 | * Show which users are online. |
| | 15 | * Maintain a chat history, and allow users who are members of a chat to see its history. |
| | 16 | * Apply access controls to the chat and its history, i.e. selectively permit users to enter a chat and see its history. |
| | 17 | * Assure security for messages. |
| | 18 | |
| | 19 | Desirable features may include the ability to... |
| | 20 | * Ping users to alert them that a message is directed to them. |
| | 21 | * Call users to the chat if they are not present. |
| | 22 | * Send out messages to a user who is offline, using their designated contact methods, and receive messages into the chat from external channels such as Twitter or SMS. |