Ethernet Switching Technology: Introduction to static switching and dynamic Switching

Static and Dynamic Ethernet Switching Technology

There are many types of Ethernet Switching Technology, each of which has its own advantages. You can use a simple mouse to increase, move, and change the structure of the exchange; network segments are more effective than bridges and routers; high bandwidth is provided for high-performance workstations or servers. Network managers are eager to use these technologies, but first they want to learn about various Ethernet Switching technologies. Currently, two Ethernet Switching technologies are available: static Ethernet Switching and dynamic Ethernet Switching.

I. Static Ethernet Switching

Static Ethernet Switching is designed for network administrators to add, move, and change network configurations through software. Static Ethernet Switching works with traditional shared network environments. Therefore, "static" is called because the network administrator needs manual intervention. Each time the network node moves and increases, the network administrator must perform operations through the network management software. Once a static switch operation is completed, the user or workstation will be moved to a new shared network segment and stay there until another new operation.

Static switching allows network administrators to easily move users from one shared LAN bus to another in one HUB. As shown in figure 1, the Ethernet Bus 1 of the hub is an Ethernet network segment shared by eight workstations of the engineering department. While Ethernet bus 4 is the network segment shared by the workstation of the marketing department, which is not marked in the figure). The above two network segments are both traditional shared LAN. What should I do when an engineer from the engineering department moves to the marketing department and wants to connect his workstation to the LAN segment Ethernet bus 4 of the marketing department?

Figure 1

For static Ethernet Switching, the network administrator only needs to use the hub graphical interface of the network management workstation to pull the port corresponding to the transferred engineer workstation from Bus 1 to bus 4. This change takes only a few seconds. The traditional method requires the network administrator to complete a series of tasks, such as checking, dialing, and re-wiring. Obviously, static switching Ethernet is extremely suitable when the network structure needs to change frequently. Static switching cannot change the bandwidth (performance). The only way you can improve the network performance is to move the workstation from a crowded network segment to an idle network segment. only dynamic Ethernet Switching can increase the bandwidth (performance) of standard Ethernet ).

Ii. Dynamic Ethernet Switching　

The initial design idea of dynamic Ethernet Switching comes from the telephone network, that is, there are many points-point sessions in a system at the same time as needed. dynamic Ethernet Switching can greatly increase the bandwidth of the network without changing the standard Ethernet node device (that is, the workstation and server use standard Ethernet cards, drivers, cables and applications. the process is as follows: the switch checks the packets from the PC; the switch recognizes the Source and Destination addresses of the packets; the switch dynamically opens a dedicated 10 Mbps link, transfer the package from the source address port to the destination address port.

Taking Figure 2 as an example, dynamic exchange checks the packets sent from workstation A to workstation B, and dynamically establishes A dedicated 10 Mbps link between A and B. obviously, unlike the traditional shared Ethernet, data packets are not sent to all workstations on the network, but are dedicated 10 Mbps links for each data transmission. the workstations and servers connected to the dynamic switching still use standard Ethernet cards, drivers, cables and applications.

Figure

Within the dynamic switching, the standard Ethernet conflict-type network access mechanism (CSMA/CD) no longer exists, and the "Conflict" with the Ethernet dependency is significantly reduced or no longer exists, each user's worker can independently enjoy all the bandwidth (10 Mbps Ethernet) of the LAN, and all data packets are exchanged through dedicated point-to-point 10 Mbps links. Therefore, Ethernet Switching is used for client/server applications, data-intensive network applications such as distributed databases, image processing, CAD, and even multimedia provide sufficient bandwidth. because the data is not frequently transmitted to all ports and the network is hard to be eavesdropped, the dynamic switching environment is safer than the shared Ethernet.

Dynamic exchange checks all data packets at the same time, and opens many 10 Mbps dedicated links for parallel data communication. in this way, many dedicated source-destination Ethernet networks can exist at any time. the point-to-point feature is similar to that of the telephone network and similar to that of the FTM. once an independent port communication is completed, the link is released dynamically. therefore, the bandwidth traffic for dynamic switching is on demand, and this on-demand bandwidth feature is another feature of the ATM network. however, because dynamic Ethernet Switching is based on standard Ethernet (standard interface cards, drivers, cables, and applications), users can retain their investment and base on the original Ethernet, obtain the same private bandwidth and security and confidentiality as ATM.

Iii. Ethernet Switching Technology Classification　

The basic differences between dynamic and static exchange in terms of functions and applications have been discussed above. The following describes the two implementation methods of each exchange technology:

Dynamic port switching

Dynamic segment Switching

Static port switching

Static module Switching

For static switching, the differences between module switching and port switching are very small. They can be used in the same scenario. For dynamic switching, the application of segment switching and port switching is obviously different.

1. Dynamic port switching

The dynamic port switching function has been described earlier. Each port is connected to a single workstation or server. because each port can be assigned an independent 10 Mbps dedicated Ethernet link as needed, this can give each workstation or server a higher network bandwidth.

2. dynamic segment Switching　

The dynamic segment switching function is similar to the dynamic port switching function. Through the switching structure, dedicated 10 Mbps dedicated links are provided as needed. each dynamic segment of the switching port can be connected to a network segment (that is, the traditional shared Ethernet), not just a workstation or service. dynamic segment switching completes this function by recognizing a large number of MAC addresses. Using a port to link the entire network segment can replace the routers and bridges in the current segmented network with dynamic segment switching.

If the user of CIDR Block A sends data packets within the CIDR Block, the exchange and identification data is the data packet of This CIDR block, and these data packets are not allowed to enter other CIDR blocks. however, if A user of network segment A sends data packets to network segment B, the switch identifies the data packets sent to network segment B and assigns A dedicated 10 Mbps link, target user who sends data packets to CIDR Block B. the network segment divides a large and crowded network into a series of small networks, each of which has small users and small traffic.

In the past, network segments were generally implemented through bridges and routers. dynamic segment switching is superior to network segments using bridges and routers for the following reasons:

(1) low price.

(2) easy to manage, and routers require complex network management at the network layer in the QSI protocol.

(3) Faster, because the exchange only detects the Source and Destination addresses in the data packet header, while the bridge and router need to detect the entire package, in this way, the latency of the exchange is much lower than that of the bridge and router.

3. Static port switching　

Static port switching allows the network administrator to move the user workstation from one shared Ethernet bus to the other through software. This allows the network administrator to flexibly increase the number of switches and reduce the order quantity of switch modules. for example, eight more users on the network work in four different departments on four different Ethernet buses. All these users can use a single port switching module. in the past, four new modules were required to connect to different bus, but most ports of each new module were not used, resulting in inefficiency and waste.

4. Static module Switching　

Static module switching is also implemented by software to increase, move, and change the network. unlike static port switching, static module switching moves the entire module (including all ports on the module) from one shared bus to another shared bus.

1. Static Routing and dynamic routing protocols
2. A comprehensive comparison between dynamic routing protocol OSPF and OSPF
3. Concepts and examples of Static Routing and Dynamic Routing