Optical module test parameter information sharing and application fields.Fiber optic equipment Manufacturing

Today, Ethernet technology has become an indispensable and irreplaceable technology in local area networks. With the wide popularization of LAN, the expansion of network scale, the rapid development of Ethernet access technology, the continuous growth of network transmission rate, and the application requirements of network interconnection and Next-generation network technology, the transmission mode, transmission capacity and quality of service of Ethernet have attracted more and more attention. Among them, transmission distance and transmission rate are the important embodiment of Ethernet transmission capability, and are the key to the transformation of Ethernet from traditional LAN technology to Metropolitan area network technology and even WAN technology. However, from a technical perspective, the higher the transmission rate, the shorter the transmission limit distance; In terms of application requirements, the higher the rate, the greater the possibility of being used for backbone transmission, and the longer the required transmission distance. Due to this contradiction and the rapid expansion of high-speed Ethernet to wider campus backbone networks and metropolitan applications, the transmission distance limitations of Ethernet related standards often face challenges: why is it limited by standard distance? Can we break through to meet the actual distance requirements?

Distance limitations of gigabit Ethernet related standards

Since the official adoption of the IEEE 802.3z Gigabit Ethernet standard in June 1998 (related to the 1000 base SX, 1000 base LX, and 1000 base CX interfaces), it has successively passed the IEEE 802.3ab Gigabit Ethernet standard (involving 1000 Base-T interfaces) and the IEEE 802.3ae 10G Ethernet standard (involving 10 Gbase Sr, 10 Gbase LR, 10 Gbase Er, 10 Gbase SW, 10 Gbase LW, 10 Gbase EW, and 10 Gbase LX4 interfaces). But for long-distance transmission of Gigabit Ethernet, the main focus is on the Gigabit Ethernet standard related to fiber optic media - IEEE 802.3z.

Key factors affecting transmission distance

There are many factors that affect the transmission distance of Ethernet, such as noise, crosstalk, etc. The key factors are media access control methods, attenuation of signal transmission, and dispersion of signal transmission. The following is an analysis of its principle, impact, and improvement methods.

For 10 Mbps and 100 Mbps Ethernet, the minimum frame length is 64 bytes, and the time slice is the delay required to send 512 bits. For 1 Gbps Ethernet, the minimum frame length is still 64 bytes, and the time slice becomes the delay required to send 4096 bits.