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Today, the editor will share with you the relevant knowledge about what is the difference between conflict domain and broadcast domain. The content is detailed and the logic is clear. I believe most people still know too much about this knowledge, so share this article for your reference. I hope you can get something after reading this article. Let's take a look at it.

1 conflict domain

We think of Ethernet as a walkie-talkie, a computer as a person using a walkie-talkie, and data transmission as talking on a walkie-talkie. Now a group of people call a real person CS, two or more people talk through the walkie-talkie at the same time, they can not hear what they are saying clearly, this is the conflict. The walkie-talkie channel can only be used by one person. Walkie-talkies and everyone who uses walkie-talkies form a conflict domain.

CSMA/CD

In order to solve the problem of collision domain, CSMA/CD (Carrier sense multiple access / collision Detection) is usually used. Its working principle is to monitor whether the channel is idle before sending data, and send data immediately if it is idle. When sending data, continue to monitor while sending. If you hear a conflict, stop sending data immediately. Wait a while and try again.

Continue to take the walkie-talkie as an example to illustrate the four contents of the control process: interception, transmission, detection and conflict handling.

1. Listen: listen to whether someone is talking before you speak. If someone is speaking, wait at random for a period of time before listening; if no one is speaking, start talking by yourself. 2. Send: when you confirm that you want to speak, start speaking immediately. 3. Detection: when you speak, multiple people may speak at the same time. Therefore, you have to listen while you speak to determine whether there is a conflict. 4. Conflict handling: when it is confirmed that a conflict has occurred, enter the conflict handling program. There are two conflict situations: a. If someone is found talking while listening, wait for a random time and listen again until you are free to talk. b. If there is a conflict while you are speaking, stop talking first, and then listen until you speak again next time. 2 broadcast domain

The broadcast in the network is just like the broadcast in our shopping mall. as soon as you open your mouth, the whole mall will hear it. The range that can be broadcast is the broadcast domain. If the broadcast domain is not maintained, a lot of bandwidth will be consumed and the efficiency of the network will be reduced.

3 the difference between conflict domain and broadcast domain

The collision domain is the first physical layer based on OSI.

Layer 1 devices have hubs, and layer 2 devices can isolate collision domains, such as switches.

The switch can narrow the scope of the collision domain, and each port switched is a collision domain.

The broadcast domain is the second data link layer based on OSI.

Layer 2 devices have layer 2 switches, and layer 3 devices can isolate broadcast domains, such as routers.

Routers can isolate broadcast domains, and each port is a broadcast domain.

4 hubs

The hub is a multi-port transponder, which can not recognize the MAC address and IP address, and sends the received data in the form of a broadcast. All its ports are both a collision domain and a broadcast domain.

The hub has a simple structure and does not have any complex network functions. It is suitable for small 100-megabit local area networks and was widely used in university dormitories more than a decade ago. With the development of the network and the increase in the number of access terminals, data collisions of hubs often occur, which leads to slow network speed due to the waste of bandwidth. at the same time, 100-megabit hubs can not meet the popular Gigabit LAN speed requirements. At present, hubs have been eliminated.

5 layer 2 switch

Layer 2 switch forwards data packets based on MAC addresses. The data sent and received by the port are independent, and each port is assigned to a different conflict domain, thus effectively isolating the conflict. The layer 2 switch forwards broadcast messages, so the broadcast domain cannot be divided.

6 Router

The router forwards IP packets based on the IP address. The router does not forward broadcast messages, so the network connected to each port of the router forms a separate broadcast domain, and the router divides the collision domain and the broadcast domain.

7 differences between hubs, layer 2 switches and routers

The hub operates at the first physical layer.

The hub forwards the message directly.

The hub can split neither the collision domain nor the broadcast domain.

The layer 2 switch operates at the layer 2 data link layer.

Layer 2 switches forward packets based on MAC addresses.

Layer 2 switch can only divide the collision domain, not the broadcast domain, and each port is a collision domain.

The router operates at the third network layer.

The router forwards the message based on the IP address.

The router divides both the collision domain and the broadcast domain, and each port is a broadcast domain.

That's all of the article "what's the difference between a conflict domain and a broadcast domain?" Thank you for reading! I believe you will gain a lot after reading this article. The editor will update different knowledge for you every day. If you want to learn more knowledge, please pay attention to the industry information channel.

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