Raiden Network（一）—— Overview

Raiden Network的优点：

• 可扩展性： 当前大多数区块链的容量都有固定或半固定的限制，而雷电网络的容量与参与者数量成正比
• 快速地： 可以在亚秒内确认转移
• 私人的： 个人转账不会出现在全球共享账本中
• 可互操作： 适用于任何遵循以太坊标准化令牌 API (ERC20) 的令牌
• 低费用： 转账费用可能比区块链低几个数量级
• 小额付款： 低交易费用允许有效地转移微小的价值

Raiden Network 的各种资料网址：

• Raiden Network 各客户端版本下载地址 https://github.com/raiden-network/raiden/releases
• Raiden Protocol Explained（雷电协议解释）： https://medium.com/raiden-network/raiden-protocol-explained-489b429fcd90
• Raiden Network 讲解视频地址： https://www.youtube.com/watch?v=jlcYmQHHutU
• 雷电网络简介： https://raiden.network/101.html
• 雷电网络协议的具体描述： https://raiden-network-specification.readthedocs.io/en/latest/introduction.html

雷电网络里简单的双向支付通道：

• Raiden balance proof： 雷电余额证明是由以太坊区块链强制执行的具有约束力的协议

支付通道网络：

• 通道的打开和关闭环节是需要上链处理的，而在雷电网络中不需要在每个节点之间建立通道，可以把其他节点作为中介进行交易。该网络及其用于路由和互锁通道传输的相关协议称为雷电网络。

雷电网络存在的不足：

• 雷电网络需要在一段时间内锁定一定的代币。
• 由于网络中每个通道余额相对较少，难以进行大量代币转移。

雷电网络的生命周期：

• 雷电网络里通道的双方用户通过来回签发 balance proof（余额证明）来进行交易。
• 当通道的其中一方想要关闭通道时，他需要向智能合约提交最新的余额证明，通道里的另一方也需要提交最新的余额证明，双方都提交了余额证明之后，他们就可以提取自己剩余的金额。（如果第二位参与者未能及时出示其余额证明，则按照提出关闭通道的一方的余额证明进行余额分配）
  

雷电网络上的多跳传输：

• 首先A得找到一条可以向D付款的多跳路径。
• D向A发送一条秘密的支付请求
• 在路径 $A\to B\to C\to D$ 上依次转发带有哈希锁的支付请求
• 然后A会向D发送解锁的秘钥
• 秘钥顺着 $D\to C\to B\to A$ 的顺序传递，在收到秘密后中间转移的每个发送者都会签署一个新的余额证明

最新版本的更新日志（09 Jun 2021）

Bespin：

A lot of work on the transport layer as well as the services went into this release. To improve performance and reliability on the transport layer it was necessary to implement some backwards incompatible changes.

Backwards compatibility status:

• v2.x clients WILL NOT be compatible with and not be able to perform transfers with any earlier versions
• The EXISTING CLIENT DATABASE WILL ALSO NOT BE COMPATIBLE.
  This means channels opened with older versions need to be closed, settled and re-opened.
  This shouldn’t cause any particular harm on test-networks. For mainnet we will provide support for users.

Changelog:

• #7120 Fix for transport potentially blocks at long http response times
• #6673 Remove refund transfers. Refunds were intended as a way to quickly unlock funds in case a transfer can’t be completed without having to wait for the lock to expire. Unfortunately they were never very good at achieving this goal and added a lot of complications to the codebase. Therefore they got removed. See the linked issue for more details.
• #7064 Fix building of binary bundles which was broken for a while.
• #6986 Increment DB version - this will make this release incompatible with previous releases. Please refer to the known issues section in the docs for details.
• #6851 Raiden does not use Matrix rooms anymore. This greatly reduces the load on the matrix servers and increases the reliability of the transport layer.
• #6898 Add support for Geth 1.10.
• #6947 Add support for Python 3.9.
• #6821 API endpoint for UserDeposit contract deposits/withdraws
• #6763 Ensure that pending messages are sent before Raiden is stopped
• #6838 Add /notifcations endpoint for showing notifications and warnings to the user.
• #6563 Faster syncing with the blockchain.
  Update WebUI to version 1.2.1. Introduces a new “Quick Connect”, that is simpler and more transparent than the old “join token network” feature, and adds a dialog for interacting with the UserDeposit contract (UDC).
• #4730 Remove “join token network” feature from API. Explicitly create and fund channels, instead.
• #6582 Add /settings endpoint with information about the used pathfinding service.
• #6657 Support for recent geth versions.
• #6541 Remove internal routing.

在雷电网络中如果交易路径的中间节点掉线了怎么办？

• 支付路径举例： $A\to B\to C\to D$
• If one of the mediating nodes stops responding (e.g. because it is offline) after the secret has been requested, it will not be possible to unlock all pending transfers before the locks expire.
  In such an instance,Dave can instead submit the secret to a smart contract called the secret registry. Upon registering the secret on-chain, the mediating nodes can see the secret, unlock their transfers, and send a signed updated balance proof to their counterparty.（Dave可以将秘密提交给一个名为“秘密登记处”的智能合约。在链上登记秘密后，中介节点可以查看秘密解锁其传输，并向其交易对手发送已签名的更新余额证明。）意思就是哪怕中间路由节点掉线话交易也可以正常进行？