Funny articles about routers and layer-3 switches

Ling huchong entered Huashan when he was 14 years old, and lazy Shan was eight years old. Yue weiqun gave directions to the two during the day, and Ling Hu at night

I told a story to tell her to fall asleep. Later, Yue Bu group received Lao de Nuo, Lu Dayou and other apprentices, and was busy repairing

Refining Zixia's power, there is no time to point to the apprentice. As a result, he made a hub, and then the Huashan school realized education electronics.

Yue Bu group taught each apprentice online at the same time. This method was quickly promoted in Wuyue jianpan. To

Yue Jianpi is interconnected with each other. Zuo Leng Chan, the manager of Song shanpi, developed a router to enable interconnection between Wuyue Jianpi.

Ling huchong told stories to her sister through the Internet at night.

Soon, laashan was sixteen years old and turned into a slim little girl. Ling Hu Chong found his eyes

I can't help but stay with my sister-in-law. Every time I stay with my sister-in-law, I can always hear my strong feelings.

After a period of tea, Ling huchong sent a message to her sister one night.

A romantic poem: You are wind, sand, bees, flowers, combs, hair, and toothpaste

It's a toothbrush.

The next day, at a regular meeting of Huashan school, Ling huchong came to the meeting room with a bad response rate and found the younger sister blushing.

Hiding behind the master, and all other younger siblings are secretly smiling at themselves. After the meeting, a naughty younger brother will come and call his teeth.

Brush brother, hurry to escape. Q: Lu Dayou, I knew it was rando who used a tool named netxray

All the online masterpieces have been captured. Ling huchong was excited, so he studied RFC in closed doors and developed

Lanswitch. It can identify the MAC address of the device, so that the data sent by Ling Hu Chong to Xiao Shimei is only one person

Yes. At night, Ling huchong can tell stories to her sister online with confidence. Occasionally, she can give her a few questions.

I wanted to say nothing to get addicted to it, and then I was blushing and imagining my face.

Lanswitch is a layer-2 switching device. It can understand the MAC address of the layer-2 network protocol address. L2 Switch in Operation

In the process, we constantly collect data to create its own address table, which is quite simple and mainly indicates a Mac location.

The address is found on which port, so when the switch receives a data packet, it will check

Check the target MAC address and its address table to determine the port from which the IP address is sent. Instead of the hub,

Any sender data will appear on all the ports of the hub (whether or not required for you ). In this way, lanswitch

While improving the efficiency, it also improves the security of the system.

In the next year, yueda group recruited a large number of disciples, and the Huashan school was greatly expanded.

Multiple secondary connections. However, it was inevitable that the disciples were mixed. At that time, the three and four generations of disciples of Huashan sent worship the man Tian bo

Guang established a tianxie, who often argued that the competition was eight hundred meters or 1 km million meters. The third generation of disciples

One of them is Li **, which broadcasts in the Huashan school every day **. What makes Ling yuchong unable to stand is that

The increasing age of Master has become more and more arrogant. Every sentence must be repeated 20 times and then broadcast on the Internet. Ling huchong

He wants to use a broadcast domain with her younger sister, Lu Dayou, and others, but if she uses another lanswitch,

Master certainly won't agree, so he modified the lanswitch software and put the younger sister, Lu daowai and himself

To form a virtual network (VLAN). Others use another VLAN. The broadcast packet is only sent within the VLAN, and

Router connection. Yue Bu-Qun is also deeply affected by Tian Xie, Li Hong, but in order to fight against Zuo Leng Chan, when employing people, he can only hide

Sorry, I was so happy to know about it, but I still want to punish him for modifying the software without permission.

Within a year. Use VLAN again in Huashan to divide subnets, which are divided into five subnets.

The father and the teacher, the younger sister, and Lin Ping are in a VLAN. ** the disciple uses a VLAN and the disciple uses a VLAN.

VLAN, another disciple uses a VLAN, and a VLAN is also available on the cliff. Linghu rushed to the cliff and

Don't be sad. Finally, the world is quiet. Relying on the router of Zuo Leng Chan, Ling Hu Chong can still give it to Xiao Shimei on the Internet every day.

Tell stories and chat.

The introduction of LAN switches enables dedicated bandwidth between network nodes. However, for layer-2 broadcast packets, layer-2 Communication

Broadcast on each network node. At the same time, it is required for MAC addresses that cannot be recognized by L2 switches.

Broadcast in the broadcast domain. When multiple L2 switches are connected, all devices in the L2 switching network will receive

Broadcast messages. In a large L2 broadcast domain, a large number of broadcasts greatly reduce the efficiency of L2 forwarding.

To avoid a broadcast storm caused by broadcasting on a large switch, you need to go further in a layer-2 switching network.

Divided into multiple virtual networks (VLANs ). In a virtual network (VLAN), information sent by a workstation can only be sent

To other sites with the same virtual network number (vlanid), other virtual network (VLAN) members cannot receive the information or

Broadcast frame. Virtual networks (VLANs) can be used to control broadcast storms on networks and increase network security. Different virtual

Communication between networks (VLANs) must be performed through routers.

However, happiness will always be short-lived, and there will always be endless troubles. With the increasing power of the entire Wuyue Sword School

The speed is getting slower and slower. Ling huchong finds that every time she tells a story to her, her answers are always from Shanshan,

There are also few things, always "well", "oh" or "I'm listening ". One day, the router cannot be pinged again.

Ling huchong didn't get the message from her sister-in-law for three days. She couldn't help it anymore, but looked at the empty display.

On the evening of the snow, I secretly went down the hill to find my sister-in-law. When I got to the window of my sister-in-law, I found my sister was chatting with me online.

Chat, did not pay attention to one side of your own, a sore heart, back to the cliff, a serious illness. Research after illness

Finally, one day, a router was created. At this time, Ling Hu Chong found that at this time, Huashan had thirty

VLAN. The router must assign an interface to each VLAN, and the interface is not enough. In addition, the two subnets pass through the Routing

The switching speed is far lower than the two-layer switching speed.

After a layer-2 switch is divided into virtual subnets, a problem occurs: forwarding between different virtual subnets needs to be implemented through

It is implemented by the router. The forwarding between different VLAN nodes of a L2 Switch needs to be achieved through the router device.

A port is wasted, and the high cost and low efficiency of the router make it unable to meet the needs of layer-3 forwarding in the case of a large number of subnets

The concept of layer-3 switching is proposed in this case.

This evening, Ling Hu was so lazy and relaxed that a black shadow appeared in front of him.

The old man of daofeng xiangu is very elegant. Feng Qingyang listened to Ling huchong's doubts and said: the router interface is not enough to route

It is not enough for the vro to be built inside the lanswitch. The switching speed is slow because the vro looks for a CIDR Block route,

While lanswitch directly queries the Mac corresponding to the port, of course, the speed is fast. Why can't I check the output end directly based on the IP address?

What? Ling huchong admired me, but he still did not understand how many IP addresses, and often changed.

Can I find the port directly? Feng Qingyang said:

"Sit down first. Let me ask you, how many disciples are there in Huashan school? "

"About sixteen thousand. "

"Do you know where they live? "

"I don't know. "

"Yue Bu group asks you to find someone who doesn't know where to live. How can you find someone? "

"Check the phone number system of Huashan Pi, find his address, and then look for him. "

"How can I find this person again after you come back? "

"How to..., check the phone number Inquiry System of Huashan school, find his address, and then look for him. "

"Do you know the address of this person? "

"Yes, but master said that Huashan has so many addresses and they often change. You don't need to know the addresses. "

"Yue weiqun, this kid, has taught his disciples to become wood! I ask you, what do you think you should find? "

"Go directly! "

"OK! You are not too benzene. After you know a person's address, do you always remember it? "

"Some people remember. I forgot everything else. "

"Why did you forget? "

"Because I can't remember so many people who haven't been looking for him for a while. "

"How do I obtain the address in the phone number query system of Huashan school? "

"I shouted his name in the open room. When he heard it, he came to me and told me his address. "

Feng Qingyang asked a lot of questions similar to the sharp turn of the brain, then Feng Qingyang said: "Now you understand that the IP address is straight

Have you found out the port? When you understand this truth, you will naturally make a layer-3 switch.

After recalling the words of today, I finally understood the same principle as layer-2 forwarding from MAC address to outbound port.

Layer-based forwarding can also be directly mapped from an IP address to an outbound port. IP address routing can be learned through arp.

To be aging. In this way, in addition to the first packet, VLAN forwarding requires Host Routing through ARP, other packets are directly transmitted.

You can find the outbound Port Based on the IP address, and the forwarding speed is much higher than the router forwarding speed. When you look up

Qingyang has already gone.

One year later, Linghu rushed down to the cliff and successfully launched the quidway s8016 route switch. Implements interconnection between VLANs

And connected To routers such as Songshan and heimu cliff.

A layer-3 switch is based on a layer-2 switch, but it is not a simple layer-2 Switch

Vro. Second, different forwarding mechanisms are used. Vro forwarding adopts the longest matching method to achieve repeat

Miscellaneous, usually implemented using software ,. Layer-3 Switch routing is targeted at the stream, and it uses the Cache Technology

It is easy to use ASIC. Therefore, it can greatly save costs and achieve fast forwarding.
It is easy to use ASIC. Therefore, it can greatly save costs and achieve fast forwarding.

Many articles will mention the difference between a layer-3 Switch and a router. Generally, a layer-3 switch is fast and cheap. This

There are no mistakes, but the scenario is the aggregation layer. We can see that in the aggregation layer, the master directly hangs down for a layer-3 Switch

Because it can obtain the route of its host, the layer-3 switch can achieve quick search.

The host that arrives after the host is connected to multiple subnets. The layer-3 switch and the router process are the same, and the longest

The matching method finds the next hop, which is forwarded by the next hop router.

Therefore, the common networking mode is to use GSR on the backbone layer, and the aggregation layer uses a layer-3 switch. Of course, for

A small man can also be directly connected to a layer-3 Switch without the need for GSR.