Network adapter, also known as network adapter or NIC (network interface controller), is a piece of computer hardware designed to allow computers to communicate on the computer network. It consists of processor, memory and other components. Network card can realize physical connection and electric signal matching between LAN transmission media. It also involves the transmission and reception of frames, encapsulation and disassembly of frames, media access control, encoding and decoding of data, and data caching functions.
The different appellations among network cards are embodied in the differences of their applications, ports and chips; they are respectively optical fiber Ethernet cards, HBA cards, wireless network cards, optical port network cards, electrical port network cards, etc. The following is a small part to explain in detail what are optical port network cards and electrical port network cards; the differences, advantages and disadvantages before them and the areas in which they are widely used;
Port Network Card: Port Network Card is also called Copper Cable Network Card. Port is the collective name of all kinds of twisted pair interfaces such as RJ45 in servers and networks. The reason is that these ports use electricity as the carrier of information, but sometimes it also includes coaxial cable ports. Usually, ports may use 100-megabit ethernet, Gigabit ethernet, Gigabit Ethernet or other kinds of transmission protocols. There are 100-megabit Ethernet card, Gigabit Ethernet card, Gigabit Ethernet card, and Gigabit Ethernet card. Generally, they are as large as those of companies and enterprises, and as small as those of desktop computers, the most commonly used Gigabit Ethernet card.
Optical Port Network Card: Optical Port is the collective name of all kinds of optical ports in servers and networks. It takes light as the carrier medium of information. Optical ports may contain various optical fiber interfaces from ST to SFF (miniaturized optical fiber connectors, mainly MTRJ and LC). Therefore, it is necessary to verify the types of optical fiber interfaces of optical ports in the later stage of wiring construction, so as to avoid the incompatibility between the presumed types of optical fiber jumpers and the requirements of actual use in wiring configuration.
That's the problem, since the port network card can achieve gigabit, Gigabit speed; why do many large server vendors, large enterprises, and Internet cafes still need to buy the optical port network card whose price is more expensive than that of the port network card; in fact, the difference lies in the efficiency of distance transmission and the rate of packet loss; the port network card uses the barrier line, that is, the common crystal head in the household, even if realized; There are already five or six kinds of equal connection methods in crystal head, which is the reason why the copper port network card can reach Gigabit or Gigabit rate, but the biggest drawback of the interface network card is that there are still many problems in transmission distance and stability. Once the transmission distance is more than 100 meters, serious packet loss will occur, even in theoretical transmission under 100 meters. Comparing with optical network card, there are some packet loss and loss. This is also a problem that can not be solved by current technology in copper material, so it makes optical network card irreplaceable.
Optical port network card (optical fiber network card) uses optical fiber for transmission; optical port conversion is carried out by optical fiber module on network card, so as to achieve the theory of infinite distance transmission in theory; and the packet loss rate and loss are very low; transmission through optical fiber transceiver can be divided into single-mode and multi-mode optical transceivers. Multimode optical fiber generally transmits more than 500 meters, and single-mode optical fiber transmission. Distance depends on specific optical fibers and specific equipment. It can be divided into single-mode and multi-mode optical transceivers. The single-mode transmission distance is 20 kilometers to 120 kilometers, and the multi-mode transmission distance is 2 kilometers to 5 kilometers.