Basic knowledge of vswitch Interfaces

Vswitch interfaces are worth learning. Here we mainly introduce the basic knowledge of vswitch interfaces. In our impression, a switch is a network device connected to a LAN node. In fact, it also exists in the Wide Area Network and is widely used, especially in telecom operators, ATM switches and fiber-channel switches, which we can hardly see at ordinary times. However, this article will introduce the interfaces and Connection Methods of common LAN switches.

As a centralized connection device for LAN, LAN switches change with the development of various LAN and transmission media types. This paper analyzes the main network types and transmission media development processes of LAN, it is not difficult to find various vswitch interface types. Next we will introduce some existing vswitch interfaces. Note that because many vswitch interfaces are identical with those of vro interfaces, therefore, the corresponding vswitch interfaces on the vro are introduced here.

Vswitch Interface Type

1. twisted pair wire RJ-45 Interface

This is the most widely used interface type we have seen. It belongs to the interface type of the twisted pair Ethernet switch. It is not only used in the most basic 10Base-T Ethernet network, but also in the mainstream 100Base-TX Fast Ethernet and 1000Base-TX Gigabit Ethernet. Although the transmission media they use are of the twisted pair type, they use different versions of the twisted pair type, for example, for the first 10 BASE-T to 6 categories that support BASE-TX gigabit speed, the 100Base-TX in the middle uses the so-called five-category and cat-5e lines. Of course, it can also be six categories. These RJ-45 interfaces look exactly the same, as shown on the left of 1, like a flat "T. Connected with the RJ-45 crystal head, 2, the right figure respectively for a crystal head and do a good job of crystal head cable twisted pair. As shown in 2 is an Ethernet switch with 24-port RJ-45 interfaces, two SC Optical Fiber interfaces and one AUI interface will be introduced below.

2. Optical Fiber Interface

Although fiber-optic transmission media has already been used in the 100Base era, this G network was called "100Base-FX" to distinguish it from the widely used g twisted pair Ethernet 100Base-TX ", the "F" is the first letter of the Fiber "Fiber. However, due to the current Mbit/s rate, compared with the traditional twisted pair Cable medium, the advantage is not obvious, and the price is much more expensive than that of twisted pair wires, so the fiber production in the Mbit/s era has not been widely used, it has been fully applied since the official implementation of 1000Base technology, because at this rate, although there are also twisted pair wires, the performance is far inferior to that of optical fibers, it has obvious advantages in connection distance and is very suitable for man and wan.

At present, the optical fiber transmission media has developed rapidly, and various optical fiber interfaces are also research. However, in LAN switches, the optical fiber interfaces are mainly SC type, either in 100Base-FX or 1000Base-FX networks. The core of the SC interface is in the connector. Figure 3 on the left shows a SC optical interface module of 100Base-FX network. The right figure shows an optical switch that provides four SC optical interfaces. As shown in figure 2, The vswitch also has two SC Optical Fiber interfaces. From figure 2 and Figure 3 right figure Switch SC interface appearance can be seen that it and RJ-45 interface is very similar, but SC interface seems more flat, the gap is lighter. Mainly look at the contact chip is what type, if it is 8 pieces of Copper shrapnel, It is the RJ-45 interface, and if it is a copper column inside is SC Fiber Interface.

3. AUI interface and BNC

The AUI interface is specially used to connect coarse coaxial cables. Although this network is rare in Lan, in some large enterprise networks, there may still be some legacy coarse coaxial cable token network equipment, so some switches also retain a few AUI interfaces to meet user needs to a greater extent. The AUI interface is a 15-pin "D" interface, similar to the display interface. This type of switch interface is also seen in many network devices, such as routers and even servers, 4 shows the AUI interface on the router.

BNC is an interface dedicated for connecting to a thin coaxial cable. Currently, vswitches that provide such vswitch interfaces are rare. However, some RJ-45 Ethernet switches and hubs also provide a few BNC interfaces, specifically used to connect to a token network with a fine coaxial cable as a transport medium. In order to show you the true appearance of BNC, the BNC interface Nic is shown below, as shown in Figure 5.

4. Console interface

We know that this interface is used to configure vswitches, so it is only available for vswitches. Note that not all vswitches are available, because there are many vswitch configuration methods, such as Telnet command line, Web, and TFTP. In theory, the basic configurations of A vswitch must be controlled through the Console). However, the basic configurations of some vswitches are configured at the factory, basic configurations such as IP addresses and basic user names are not required. Therefore, vswitches of this type do not need to provide this Console interface, and currently the majority of vswitches are available. This type of switch usually requires some advanced configuration through simple Telnet or Java program Web.

Of course, some vswitches still provide Console interfaces, but note that not all vswitches use the same Console ports for vswitch configuration, some use the same RJ-45 type Console interface as the Cisco router, as shown in 6. Some use the serial port as the Console interface, as shown in figure 7. It can be seen that the Console ports of the two vswitches are different. They are in the form of a "D" interface with the "mother" header and 9-pin "D" interface. They are commonly known as the "DB-9" interface, but are configured with a switch. In addition to the two vswitch Console ports, there is also an interface that is also commonly used in vswitch configuration, that is, the 25-pin "D" interface.

Whether the switch uses the DB-9 or DB-25 serial interface, or the RJ-45 interface, in the switch configuration, generally need to connect to the configuration through a dedicated Console line with a computer usually called a terminal) of the serial port, compatible with different Console ports of the vswitch. The Console line is also divided into two types: one is a serial line, that is, both ends of the serial interface are the master or one end is the public header, and the other end is the master ), the two ends can be inserted into the computer's serial port and the Console port of the switch; the other is the two ends are RJ-45 joint RJ-45-to-RJ-45) flat line. Since both ends of the flat line are RJ-45 interfaces, you cannot connect directly to the computer's serial port, so you must also use an 8 RJ-45-to-DB-9 or RJ-45-to-DB-25 at the same time. Typically, such a Console line and the corresponding DB-9 or DB-25 adapter will be randomly presented in the switch box.

5. FDDI Interface

In the early Mbps era, there was also an FDDI network type. Its Chinese name was "Fiber Distributed Data Interface", and obviously its transmission media was also optical fiber, its interface type is mainly SC type. At present, because of its inconspicuous advantages, it has basically disappeared.

As for the switch interface type, we will only introduce the above, of course there will be some switch interface types, such as the aforementioned ATM network interface, in addition, the type of the optical network interface is far more than SC. However, in enterprise LAN switches, these switch interfaces are usually not met, so we will not detail them here.