了解继电器政策及其对比特币网络的影响

在上一篇MEMPOOL文章中，我介绍了不同种类的继电器策略过滤器，为什么它们的存在以及最终决定每类过滤器如何防止确认不同类型交易的激励措施。

In the last Mempool article, I went over the different kinds of relay policy filters, why they exist, and the incentives that ultimately decide how effective each class of filter is at preventing the confirmation of different classes of transactions. In this piece I’ll be looking at the dynamics of the relay network when some nodes on the network are running different relay policies compared to other nodes.

在上一篇MEMPOOL文章中，我介绍了不同种类的继电器策略过滤器，为什么它们的存在以及最终决定每类过滤器如何防止确认不同类型交易的激励措施。在本文中，当网络上的某些节点与其他节点相比，该网络上的某些节点正在运行不同的中继策略时，我将研究中继网络的动态。

All else being equal, when nodes on the network are running homogenous relay policies in their mempools, all transactions should propagate across the entire network given that they pay the minimum feerate necessary not to be evicted from a node’s mempool during times of large transaction backlogs. This changes when different nodes on the network are running heterogenous policies.

所有其他都是平等的，当网络上的节点在其孟买群岛中运行同质继电器策略时，所有交易都应在整个网络中传播，因为它们在大型交易背积蓄期间支付了最小的费用。当网络上的不同节点运行异质策略时，情况会发生变化。

The Bitcoin relay network operates on a best effort basis, using what is called a flood-fill architecture. This means that when a transaction is received by one node, it is forwarded to every other node it is connected to except the one that it received the transaction from. This is a highly inefficient network architecture, but in the context of a decentralized system it provides a high degree of guarantee that the transaction will eventually reach its intended destination, the miners.

比特币中继网络使用所谓的洪水填充体系结构在最佳努力下运行。这意味着，当一个节点收到交易时，它会转发到其他节点，除了从收到交易的节点之外，它已连接到。这是一个高效的网络体系结构，但是在分散系统的背景下，它提供了高度保证，即交易最终将最终到达其预期目的地，即矿工。

Introducing filters in a node’s relay policy to restrict the relaying of otherwise valid transactions in theory introduces friction to the propagation of that transaction, and degrades the reliability of the network’s ability to perform this function. In practice, things aren’t that simple.

在节点的继电器策略中引入过滤器，以限制理论中原本有效的交易的继电器引入摩擦到该交易的传播，并降低网络执行此功能的能力的可靠性。实际上，事情并不那么简单。

How Much Friction Prevents Propagation

多少摩擦阻止传播

多少摩擦阻止传播

Let’s look at a simplified example of different network node compositions. In the following graphics blue nodes represent ones that will propagate some arbitrary class of transactions known to be consensus valid, and red nodes represent ones that will not propagate those transactions. The collective set of miners is denoted in the center as a simple representation of where transacting users ultimately want their transactions to wind up so as to eventually be confirmed in the blockchain.

让我们看一下不同网络节点组成的简化示例。在以下图形中，蓝色节点代表将传播一些任意类型的交易类别，已知的共识有效，红色节点代表不会传播这些交易的节点。集体矿工在中心表示，是交易用户最终希望其交易结束的简单表示，以最终在区块链中确认。

This is a model of the network in which the nodes refusing to propagate these transactions are a clear minority. As you can clearly see, any node on the network that accepts them has a clear path to relay them to the miners. The two nodes attempting to restrict the transactions propagation have no effect on its eventual receipt by miners’ nodes.

这是网络的模型，其中节点拒绝传播这些交易是明显的少数。正如您可以清楚地看到的那样，网络上接受它们的任何节点都有一个明确的途径将其传达给矿工。试图限制交易传播的两个节点对矿工节点的最终收据没有影响。

In this diagram, you can see that almost half of the example network is instituting filtering policies for this class of transactions. Despite this, only part of the network that propagates these transactions is cut off from a path to miners. The rest of the nodes not filtering have a clear path to the collective set of miners. This has introduced some degree of friction for a subset of users, but the others can still freely engage in propagating these transactions.

在此图中，您可以看到示例网络的几乎一半是在为此类型的交易制定过滤策略。尽管如此，只有传播这些交易的网络的一部分才从矿工的道路上切断。未过滤的其余节点具有通往集体矿工的清晰路径。这已经为一部分用户引入了一定程度的摩擦，但其他用户仍然可以自由参与传播这些交易。

Even for the users that are affected by filtering nodes, a single connection to the rest of the network nodes that are not cut off from miners (or a direct connection to a miner) is necessary in order for that friction to be removed. If the real relay network were to have a similar composition to this example, all it would take is a single new connection to alleviate the problem.

即使对于通过过滤节点影响的用户，也必须与矿工（或与矿工直接连接）切断的网络节点的单个连接，以便删除这种摩擦。如果真实继电器网络与此示例具有类似的组成，那么它就需要采取的单个新连接来减轻问题。

In this scenario, only a tiny minority of the network is actually propagating these transactions. The rest of the network is engaging in filtering policies to prevent their propagation. Even in this case however, those nodes that are not filtering have a clear path to propagate them to miners.

在这种情况下，只有一小部分网络实际上是在传播这些交易。网络的其余部分正在进行过滤政策以防止其传播。但是，即使在这种情况下，那些没有过滤的节点也有清晰的途径将其传播给矿工。

Only this tiny minority of non-filtering nodes is necessary in order to ensure their eventual propagation to miners. Preferential peering logic, i.e. functionality to ensure that your node prefers peers who implement the same software version or relay policies. These types of solutions can guarantee that peers who will propagate something another node won’t find each other and maintain connections amongst themselves across the network.

为了确保他们最终向矿工传播，只有少数非过滤节点才有必要。优先的对等逻辑，即功能，以确保您的节点更喜欢实现相同软件版本或中继策略的同行。这些类型的解决方案可以保证，传播某个节点的同行不会彼此找到彼此，并在整个网络中保持联系。

The Tolerant Minority

宽容的少数

宽容的少数

As you can see looking at these different examples, even in the face of an overwhelming majority of the public network engaging in filtering of a specific class of transactions, all that is necessary for them to successfully propagate across the network to miners is a small minority of the network to propagate and relay them.

正如您所看到的那样，即使面对绝大多数公共网络的绝大多数示例，他们从事过滤一类特定的交易，他们在整个网络中成功传播给矿工所必需的一切都是少数网络传播和中继它们的网络。

These nodes will essentially, through whatever technical mechanism, create a “sub-network” within the larger public relay network in order to guarantee that there are viable paths from users engaging in these types of transactions to the miners who are willing to include them in their blocks.

这些节点基本上将通过任何技术机制，在较大的公共继电器网络中创建一个“子网络”，以确保从从事这些类型的交易到愿意将它们包括在其街区中的矿工的用户有可行的途径。

There is essentially nothing that can be done to counter this dynamic except to engage in a sybil attack against all of these nodes, and sybil attacks only need a single honest connection in order to be completely defeated. As well, an honest node creating a very large number of connections with other nodes on the network can raise the cost of such a sybil attack exorbitantly. The more connections it creates, the more sybil nodes must be spun up in order to consume all of its connection slots.

基本上，除了对所有这些节点进行SYBIL攻击之外，Sybil攻击只需要一个诚实的联系即可完全被击败，因此无能为力。同样，一个诚实的节点与网络上的其他节点建立了很大的连接可以使Sybil攻击的成本高涨。它创建的连接越多，必须旋转的Sybil节点越多才能消耗其所有连接插槽。

What If There Is No Minority?

如果没有少数怎么办？

如果没有少数怎么办？

So what if there is no Tolerant Minority? What will happen to this class of transactions in that case?

那么，如果没有宽容的少数民族怎么办？在这种情况下，这类交易会发生什么？

If users still want to make them and pay fees to

如果用户仍然想赚钱并支付费用