Gigabit Switch

Many people looking for more rapid LAN connection technology, using Gigabit Ethernet or faster million trillion technology. This change is not just happened in the campus network backbone, also occur in every closet, enterprise IT management staff hope for every desktop users 10 times in the previous network connection.

Gigabit switch.

Selection for many reasons, understanding is the selection of the foundation. You understand the Gigabit Ethernet switch? In this period the switch magazine, we choose such a proposition, hoping to take you into the Gigabit switches have a look inside, how it works, how to form, why to have so different, and so on. With the settlement of these problems, the product of your choice will be more strong.

Gigabit switch type

Equipment manufacturers in the design of the switch, usually through different settings to meet customer demand, these requirements are typically include the following:

1 can be stacked to obtain full scalability;

2 can pass through the machine frame structure is obtained by elastic backbone expansion capability;

3 and the server can equipment integration, to achieve the calculation and network integration;

4 small and medium enterprises will require a fixed port or may work independently switch; 5 not for the IT Department small company, blame management equipment will be more popular.

There are some other requirements, such as reducing the design, production and assembly cost. Many of these demands are contradictory, but they are also real. To satisfy their way through different types of switches product to achieve, and the continuous progress of the semiconductor technology makes the switch design and manufacturing has entered the high modularization and integration phase, to design different types of switches and provides technical convenience. Here, we show different types of switches by its design principle and system structure, to help you decide what kind of switch is you really need.

Stackable switch

These switches are often used to connect users to the high speed campus network backbone. Usually, some of them are called high-speed" user" port, and has strong expansibility. When data from these ports collect, from high speed data interchange road passes out, in order to achieve and the center server, IP PBX and other equipment data exchange. Stackable switches are usually placed in the closet or in the engine room, it can be adapted to the growth of network. If a new user to join the network, the administrator simply in the original equipment placed above a new device, and then through an external " stacked" interface all the switches connect. In fact, this is your own and the development of a new, larger switches, can be conveniently and the original switch managed together, just a capacity increased.

There is a high speed stacking stackable switch port is the basic characteristic of.

Machine frame type switch

This type of switch used in the high performance network backbone layer. The system has a lot of slots, can be used to insert a lot of redundant network interface card, includes a system bus, power supply, security module. The whole system can be set to high redundancy system, in uncontrolled disaster or failure can still provide the available network services. Performance is a machine frame type equipment important indicators, but more important is the system of high reliability and high availability. Its failure rate is usually required in the average annual overhaul time of less than 5 minutes.

If the figure 2 stackable switches on the stacking port connected with a larger exchange capacity switching array chip switch backplane, and redundant power supply and management module design, constitute a core of the machine frame type switch. High speed switching array chip structure as shown in figure 3.

Independent ( fixed port ) switch

This is the most common switch, it for growth-oriented enterprises to provide cheap network solutions. The system has a fixed interface ( not expanded ), when the growth of enterprises need to expand the switch port number, a network administrator must buy some switches.

In general, the switch structure and a general computer very similar. The switch has its own CPU, memory, external memory FLASH ( functionally similar computer hard disk ), start memory (similar to the computer's BIOS ) as well as the importance of the exchange chip and a network interface chip ( similar to a computer network card ).

General computer is different, network interface chip after receiving the data, most of it through the exchange chip implementation of storing and forwarding operation, not the system through the CPU, the above mentioned independent ( fixed port ) switches and unmanaged switch is one such structure. The difference is, the independent ( fixed port ) switch just in port extended slightly lost in more advanced switches, but depending on the design, the system can be used in very advanced CPU and large amounts of memory. Such a multilayer switch can be used by system CPU to handle such as routing, network security strategy, the realization of advanced network applications. Many switches use the common CPU, certainly not our common Intel, but like the Motorola MPC8245 or MIPS RISC chip.

BCM5464

It is a 4 port Gigabit transceiver with integrated electrical signals, copper / fiber medium interface. This is what we called a network interface chip, it needs and fiber optic or copper physical layer device ( PHY ) to work together, constitute the original signal receiving interface ethernet. Then, it upward and a 12 port Gigabit Ethernet exchange chip connection, three BCM5464 passed to 12 Gigabit signals in exchange chip BCM5691 completion of the exchange, the exchange chip, will establish corresponding MAC learning mechanism and the mapping table, and then through the corresponding BCM5464 forwarded to destination port.

Can not be managed switches, because demand is more simple, so the design can use less memory and less energy consumption, lower cost of CPU, common ARM kernel CPU. This simple design is just to start system, simple control instructions to download exchange chip, unable to complete the high-level exchange.