Optimizes wireless switches to ensure data availability.

Source: Internet
Author: User

In the enterprise wireless LAN, wireless switches are used for integrated data transmission and distribution. Its management function enables our data to flow in an orderly manner. In the work process, wireless switches will also lag behind. So how should we optimize the data exchange of wireless switches?

Different ways of working let's first talk about the concepts of sharing and exchange in the network. Here, for example, we use 10 lanes of roads. if the road is not marked with a clear route, therefore, vehicles can only snatch or occupy the road in a disordered state, which is prone to traffic jams and reverse vehicle collisions, reducing the traffic capacity 。

To avoid the above situation, we need to optimize the work of the wireless switch. First of all, we need to know that we need to mark the vehicle lines on the road to ensure that each vehicle runs its own way and does not interfere with each other. The shared network is equivalent to the disordered state mentioned above, when the number of data and users exceeds a certain limit, a collision or conflict will occur, resulting in a decline in network performance 。

The exchange network avoids the deficiency of the shared network. The exchange technology is to independently send each information packet from the port to the destination port based on the destination address of the transmitted information packet, it avoids collision with other ports and increases the actual throughput of the network 。

The main problem with shared Ethernet is that all users share bandwidth. The actual available bandwidth of each user decreases with the increase of the number of users. This is because when the information is busy, multiple users may compete for one channel, while only one user occupies one channel at a time. Therefore, a large number of users are often waiting for monitoring, as a result, the signal is jittery, stagnant, or distorted during transmission, seriously affecting the network performance. This is the prerequisite for optimizing the wireless switch.

In switched Ethernet, a wireless switch provides a dedicated information channel for each user, unless two source ports attempt to send information to the same destination port at the same time, otherwise, the source port and the target port can communicate at the same time without conflict 。

The operations of a vswitch are completely different. It obtains the target MAC address by analyzing the packet header information (including the original MAC address, target MAC address, and information length, find the address table (the port corresponding to the MAC address) stored in the vswitch, confirm the port on which the NIC with this MAC address is connected, and then only send the packet to the corresponding port, effectively suppress the generation of broadcast storms 。

This is the biggest difference between the Switch and the HUB. The bandwidth of the Switch's internal conversion packet is much larger than the port bandwidth. Therefore, the packet is in parallel and the efficiency is high, it can meet the parallel processing requirements of massive data in a large network environment 。

The difference in the bandwidth usage mode: no matter how many ports the hub has, all ports share a bandwidth. At the same time, only two ports can be used to transmit data, and other ports can only wait, at the same time, the hub can only work in half duplex mode. For a wireless switch, each port has an exclusive bandwidth, which guarantees the speed of each port 。

When two ports work, other ports are not affected, at the same time, the switch can not only work in half duplex mode, but also work in full duplex mode. The difference in transmission mode: the hub can only be transmitted in half duplex mode, because the hub is a shared transport medium, in this way, the hub can only transmit one task at a time on the uplink channel, either to receive data or to send data 。

The switch is different. It uses full duplex mode to transmit data. Therefore, data can be received and sent at the same time, which not only speeds up data transmission, in addition, the throughput of the entire system is at least twice faster than that of the hub, because it can receive and send at the same time, in fact it is far more than doubled, because the port bandwidth is generally many times wider than the hub 。

For example, if two groups of people transmit a file to each other at the same time, the transfer time from one person to the other is one minute, it takes four minutes. Data is first transmitted from one person to the other, and then from the other, in this case, it will take 4 minutes, but the speed will be much faster with the switch. In the same case, it will only take 1 minute 。

Because each port is independent, the two groups can transmit data at the same time. Because the switch can work in full duplex mode, each two people can also transmit data at the same time, in other words, these four people completed the work within the same time. Therefore, we can also regard the processing capabilities of hubs and wireless switches as serial processing and parallel processing 。

In daily life, the Internet access will certainly involve wireless switches, which provide users with exclusive point-to-point connections. data packets are only sent to the destination, so as to avoid a significant reduction in the bandwidth of all ports when the data volume is large, therefore, selecting a high-performance wireless switch saves a lot of trouble for future work. However, due to the network structure or other reasons, data transmission and receiving problems may occur, it is necessary to optimize the wireless switch effectively.

When used for a star structure, it acts as the center node to enlarge the signal. The port does not share the bandwidth. If it is a 10 M switch, the bandwidth of each port is 10 M, each port has its own MAC address. The main functions of the switch include physical addressing, network topology, error verification, frame sequence, and traffic control 。

At present, some high-end switches also have some new functions, such as VLAN (Virtual LAN) Support and link aggregation support, some even have routing and firewall functions. In addition to connecting to the same type of network, a switch can also act as a connection between different types of networks (such as Ethernet and Fast Ethernet 。

Nowadays, many vswitches can provide high-speed connection ports that support fast Ethernet or FDDI, it is used to connect other switches in the network or provide additional bandwidth for key servers with high bandwidth usage. It is a network device and has some functions of a router, it can decide where the received data is sent, and its speed is faster than that of the router 。

Contact Us

The content source of this page is from Internet, which doesn't represent Alibaba Cloud's opinion; products and services mentioned on that page don't have any relationship with Alibaba Cloud. If the content of the page makes you feel confusing, please write us an email, we will handle the problem within 5 days after receiving your email.

If you find any instances of plagiarism from the community, please send an email to: info-contact@alibabacloud.com and provide relevant evidence. A staff member will contact you within 5 working days.

A Free Trial That Lets You Build Big!

Start building with 50+ products and up to 12 months usage for Elastic Compute Service

  • Sales Support

    1 on 1 presale consultation

  • After-Sales Support

    24/7 Technical Support 6 Free Tickets per Quarter Faster Response

  • Alibaba Cloud offers highly flexible support services tailored to meet your exact needs.