近期Aeternity的状态通道更新比较多，做个笔记：

• Introduces State Channel FSM Generalized Accounts awareness. It now fully supports creation of meta transactions and verifies them.

• Enhances the state Channels WebSocket API, that now supports starting a responder with "initiator_id": "any". The responder instance will get the proper initiator Id from the channel_open message once a connection is established.
  

• Enables multiple different State Channel responder pubkeys to share the same listen port.

• Changes the channel_open and channel_accept messages to contain both the initiator and responder public keys. This is not backwards compatible for the noise protocol.

• Enhances State Channel's WebSocket API with providing more meaningful messages when failing to open a channel because of invalid opening arguments.

• Makes State Channel WebSocket API more consistent regarding the usage of caller and contract vs caller_idand contract_id. This is an API breaking change.

• Allows sending and receiving generic messages in State Channels in any FSM state. Until this - generic messages were allowed only in open state. channel_id is part of the message body and if it is unknown - the temporary one is used instead. This is not backwards compatible for the noise protocol. This enhances the WebSocket API accordingly.

• Makes State Channel FSM more robust to timeouts. If one of the peers refuses signing the closing transaction while the channel is not active then the request may timeout without killing the FSM.

• Improves State Channel FSM to compute transaction fees in a dynamic manner. This will usually result in smaller fees being paid by participants.

• Enhances the State Channel user experience adding info regarding timeouts. The process that handles the state for the State Channel client in the node has a list of different timeouts. They define different time frames for certain events to be completed. Running out of time is a violation of the off-chain protocol so if it happens - the connection is closed and it is up to the State Channel client how to proceed next. This enhances user experience adding a new info message for the timeouts.

• Enables State Channels Websocket clients to reconnect and to re-attach to the FSM, using a special signed offchain transaction. While the client is disconnected, the corresponding FSM will reject requests that require signatures.