冲突域和广播域_两个交换机广播域的个数-优快云博客

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注：机翻，未校。

What are the collision domain and broadcast domain?

By Imran Ullah Khan

Collision domain and Broadcast domain are the two important terms in the computer networking subject. it defines how data will access the medium. If more than one device sends data at the same time, then there is a chance to collide that data with another device’s data. Also, the Broadcast domain defines the reachability of a message to travel across the network. We will explain the collision domain and broadcast domain in the following paragraphs.
冲突域和广播域是计算机网络学科中的两个重要术语。它定义了数据将如何访问媒体。如果多个设备同时发送数据，则有可能将该数据与另一台设备的数据发生冲突。此外，广播域还定义了消息在网络上传输的可达性。我们将在以下段落中解释冲突域和广播域。

Collision Domain 冲突域

The collision domain consists of two words: ‘Collision,’ which means ‘to collide,’ and ‘Domain,’ which denotes an area or region. Therefore, collisions take place within a network or a portion of it. When two or more devices attempt to transmit data simultaneously on a shared network segment, a collision occurs. For instance, if a group of computers connected through a hub attempts simultaneous data transmission, a collision domain may form.
冲突域由两个词组成：“冲突”，指的是 “发生冲突”，以及 “域”，表示一个区域或范围。因此，冲突发生在网络或其一部分内。当两个或多个设备尝试在共享的网络段上同时传输数据时，就会产生冲突。例如，如果通过集线器连接的一组计算机尝试同时传输数据，就可能形成一个冲突域。

collision domain

Another technical definition of it is “it is a group of Network NICs in which collision can occur. It occurs in different computer networking devices. It takes place in a Hub, Bridge, Switch, and Router Every port in a hub is in one collision domain. Each port on the Bridge, Switch, and router is in a separate collision domain. Hub is a shared medium, so all the ports in a hub will be in the same collision domain. Bridge, Switch, and router ports are in different collision domains, e.g. if a switch, or bridge has 16 ports, then there will be 16 collision domains. Every interface of a router is in a different collision domain.
冲突域的另一个技术定义是 “它是一组可能发生冲突的网络接口卡”。这种情况出现在不同的计算机网络设备中。冲突发生在集线器、网桥、交换机和路由器中。在集线器中，每个端口都处于同一个冲突域。而在网桥、交换机和路由器中，每个端口则处于不同的冲突域。集线器是一个共享媒介，因此集线器中的所有端口将位于同一个冲突域。网桥、交换机和路由器的端口则处于不同的冲突域。例如，如果一个交换机或网桥有 16 个端口，那么就会存在 16 个冲突域。每个路由器的接口也处于不同的冲突域。

Broadcast Domain 广播域

Broadcast domain is a combination of two words, Broadcast and domain. The term Broadcast means “those messages that are sent to all devices in the network at once”. It is a type of one-to-all communication, while domain means area or region. All the devices in the network can reach other devices through broadcast. The Broadcast Can occur in the hub, or switch.
广播域是由两个词组成的：广播和域。广播这个术语指的是 “那些同时发送给网络中所有设备的消息”。这是一种一对多的通信方式，而域则表示区域或范围。网络中的所有设备都可以通过广播与其他设备进行通信。广播可以发生在集线器或交换机中。

A more technical definition of the Broadcast domain is a “group of network interface cards in which one NIC sends a Broadcast, then the other devices will receive that broadcast or message”. It takes place in the Hub, Bridge, Switch, and Router. All ports in hub and switch are in the same Broadcast domain. Each port in a router is in disparate broadcast domains.
广播域的一个更技术性的定义是 “一组网络接口卡，其中一个网卡发送广播，然后其他设备将接收该广播或消息”。它发生在集线器、网桥、交换机和路由器中。集线器和交换机的所有端口都在同一个广播域中。路由器中的每个端口都在不同的广播域中。

From the above screenshot, it is clear that the Switch has one broadcast domain, while the number of collision domains of a swotcj depends number of ports. If a switch has 24 ports, then it will contain 24 collision domains. Every port of a switch is in a different collision domain.
从上图中可以清楚地看出，Switch 有一个广播域，而 swotcj 的冲突域数量取决于端口的数量。如果交换机有 24 个端口，则它将包含 24 个冲突域。交换机的每个端口都位于不同的冲突域中。

Similarly, a hub has only one collision domain and one broadcast domain. So, All the ports on the hub is in the same collision domain.
同样，一个中心只有一个冲突域和一个广播域。因此，集线器上的所有端口都位于同一冲突域中。

Different Scenario 不同的场景

In the below screenshots, we explain very well the collision domain and broadcast domain.
在下图中，我们很好地解释了冲突域和广播域。

We defined in the screenshot, that there is only one broadcast domain, while there are Five collision domains in the network.
在截图中，只有一个广播域，而网络中有五个冲突域。

In the above diagram or network, we have created three different VLANs. We also know that every vlan is in a different broadcast domain because the basic purpose of VLAN is to break the broadcast domain into smaller parts or networks. As there are three VLANs in the network, there are three broadcast domains in it. While the number of collision domains depends on on the number of PCs that exist in the vlan. As VLAN 1 has three PCs, but all the PCs are connected to the hub, so they are all in the same collision domain. Similarly, VLAN 2 has two PCs, so it has two collision domains, while VLAN 3 has also two PCs. So, it has also two collision domains.
在上图或网络中，我们创建了三个不同的 VLAN。我们还知道，每个 VLAN 都位于不同的广播域中，因为 VLAN 的基本目的是将广播域分解为较小的部分或网络。由于网络中有三个 VLAN，因此其中有三个广播域。冲突域的数量取决于 VLAN 中存在的 PC 数量。由于 VLAN 1 有三台 PC，但所有 PC 都连接到集线器，因此它们都位于同一冲突域中。同样，VLAN 2 有两台 PC，因此它有两个冲突域，而 VLAN 3 也有两台 PC。因此，它还有两个冲突域。

So, the total number of Broadcast domains is Three, while the total number of collision domains is 1+2+2=5, and Five is the total number of collision domain that exists.
因此，广播域的总数为 3，而冲突域的总数为 1+2+2=5，而 5 是存在的冲突域总数。

Likewise in the same way, we are going to take a third scenario, in which we also take a router in the network.
同样，以同样的方式，我们将采用第三种情况，在这种情况下，我们还在网络中使用路由器。

Every interface of a router is in a different broadcast domain. So, it has two broadcast domains. Moreover, there are 9 collision domains in the network as shown above in the diagram.
路由器的每个接口都位于不同的广播域中。因此，它有两个广播域。此外，网络中有 9 个冲突域，如上图所示。

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