Gigabit Ethernet Specification

Gigabit Ethernet Specification

Because Gigabit Ethernet technology is still one of the most mainstream applications of Ethernet technology, so the specification of this Ethernet is still being introduced to meet the needs of different application environments, improve technical performance.

Earliest in1998and the1999released in the yearIEEE 802.3zand theIEEE 802.3abthe standard includes1000BASE-LX,1000BASE-SX,1000base-cxand the1000base-t(the first three types are collectively referred to as1000base-xSub-series),5-12is shown. The first three of them areIEEE 802.3zStandard, and1000base-tThe standard is determined by theIEEE 802.3abprescribed, is specially developed in the back. It4Gigabit Ethernet Specification supports different types of fiber and twisted pair cables.

However, in industrial applications, although some specifications are not formally published in standard form (or not byIEEEpublished), but it's actually a wide range of applications. As1000BASE-LH,1000BASE-ZX,1000base-lx10,1000base-bx10,1000base-txthese five kinds of specifications. In this way, the Gigabit Ethernet series adds up to a total of9the code of Practice. In this9type of Gigabit Ethernet specification, according to the types of transmission media used, generally divided into two categories: fiber-based and twisted-pair-based. The following are presented separately.

1. Specification for Gigabit Ethernet based on optical fiber

The gigabit rate has been quite high, from the overall performance, the most suitable medium is the fiber, so since the gigabit Ethernet, including the back of the million, and even now is studying theTenThe vast majority of Gigabit Ethernet specifications are based on the transmission medium of optical fiber. In the above9Gigabit Ethernet Specification, there is6The species is based on fiber optics. They were published in standard form:1000BASE-LXand the1000BASE-SXand whether it has been published in the standard form:1000BASE-LH,1000BASE-ZX,1000base-lx10and the1000base-bx10.

1000base-lx

This is a Gigabit Ethernet specification for communication over optical fibers that can be used with single mode fiber (SMF), you can also use multimode fiber (MMF). 1000BASE-LXusing a long wavelength laser, the wavelength is1310nm;1000BASE-LXThe main fibers used are: wire diameter62.5nmmulti-mode fiber,50nmMultimode Fiber and9nmsingle-mode fiber. where the maximum transmission distance using multimode fiber is550m, the maximum transmission distance using a single mode fiber is5km; adopt8b/10bdata encoding method, mainly applicable to campus or Metro backbone network.

1000base-sx

This is also a Gigabit Ethernet specification for communication via optical fiber, suitable for wire cores50nmand the62.5nmthe short wave (wavelength is850nm) multimode Fiber (MMF). which uses62.5nmthe maximum transmission distance of multimode fiber is275m, using50nmthe maximum transmission distance of multimode fiber is550m. 1000BASE-SXSpecifications adopted8b/10bdata encoding method, which is suitable for the backbone path of the building network system.

1000base-lh

This is a non-standard specification, but has been widely accepted as the de facto Gigabit Ethernet specification in industry. 1000BASE-LH the use of the wavelength is 1300nm or 1310nm single-mode or multimode long-wavelength fiber. It is similar to the 1000BASE-LX specification, but the longest effective transmission distance in a single-mode high-quality fiber is up to 10kmandcan be 1000BASE-LX Network remains compatible.

1000base-zx

This is also a non-standard specification, but has been widely accepted as the de facto Gigabit Ethernet specification in industry. 1000BASE-ZX the use of the wavelength is 1550nm Shuan long-wavelength fiber. Maximum effective transmission distance of up to 70km.

1000base-lx10

This is also a non-standard specification, but has been widely accepted as the de facto Gigabit Ethernet specification in industry. 1000base-lx10 the use of the wavelength is 1310nm single-mode long-wave fiber. Maximum effective transmission distance of up to 10km.

1000base-bx10

This is also a non-standard specification, but has been widely accepted as the de facto Gigabit Ethernet specification in industry. 1000base-bx10 The type of transmission media used by the two fibers is different: the downstream direction (from the network Center to the outside) uses a wavelength of 1490nm Shuan long wavelength fiber, the upstream direction is the use of 1310nm single-mode long-wave fiber. The maximum effective distance is 10km.

2. Specification for Gigabit Ethernet based on twisted-pair wires

In the Gigabit Ethernet specification, the following three are used as transmission media with twisted-pair wires:

1000base-cx

This is a 150Ω Balanced shielded twisted pair (STP) as a transmission medium (connector DB-9), with a maximum transmission distance of only 25m , the data encoding method uses 8b/10b, which is suitable for inter-data center devices (such as connections between switches, especially for short-distance connections between backbone switches and primary servers), or for short-distance interconnection between stacked devices. However, it does not apply to the connection between the data center and the wiring rack.

1000base-t

This is a way to use5class, Super5class,6class or7classUTPTwisted pair of all4the Gigabit Ethernet specification for Core wire as a transmission medium, the corresponding standard isIEEE 802.3ab(different from other Gigabit Ethernet standards). It has a maximum transmission distance of100m. In all the4in the twisted-pair core line, each pair can simultaneously carry on the data to send and receive, therefore even is the same equipment between the connection, also does not need to make the intersection line, both ends use the same wiring standard.

1000base-tx

There is also a common standard in the Gigabit Ethernet standard, which is 1000base-tx, but it is not developed by the IEEE , but by Tia/eia in 1995 published in the year, the corresponding standard number is tia/eia-854.

Although1000base-txis based on4for twisted-pair wires, but with Fast Ethernet100base-txA standard-like transport mechanism, which is sent with two pairs of lines, is received by two pairs of wires (similar to100base-txa pair of lines to send, a pair of lines to receive). As each pair of cables itself does not carry out two-way transmission, the crosstalk between the cables is greatly reduced, and the encoding method is also8b/10b. This technology has a low requirement on the interface of the network, it does not need very complicated circuit design, and reduces the cost of the network interface. But because the efficiency of using the cable is reduced (two pairs of lines, two pairs of wire), to achieve1000mb/stransmission rate, which requires more bandwidth than100MHz, which means that in5class and Super5class does not support this type of network, you must6class or7support for class twisted pair systems.

The comparison of the above 9 Gigabit Ethernet specifications is shown in table 5-6 , where the main advantages and characteristics of each specification can be seen.

Table 5-6 Comparison of 9 Gigabit Ethernet Specifications

Gigabit Ethernet Specification	Transport media used by the specification	Effective precocious
1000base-cx	150ω Twisted pair Cable	25m
1000base-lx	Single-mode or multimode fiber with a wavelength of 1310nm	5km
1000base-sx	Multimode fiber with a wavelength of 850nm	500m
1000base-lh	Single-mode or multimode fiber with a wavelength of 1310nm	10km
1000base-zx	Single-mode fiber with wavelength of 1550nm	70km
1000base-lx10	Single-mode fiber with wavelength of 1310nm	10km
1000base-bx10	A single mode fiber with a wavelength of 1490nm, Single-mode fiber with 1310nm behavior wavelength	10km
1000base-t	Class 5, Super 5, Class 6, or 7 twisted pair	100m
1000base-tx	Class 6 or Class 7 twisted pair	100m

Gigabit Ethernet Specification