Depth analysis of twisted-pair and its connection

Today, the development of the computer is changing, with the popularity of computer. Many home users already have two or more computers. Set up a home network,cheap christian louboutin, campus network; LAN area ... .... Is not what it is. Interconnection network, information transmission, are inseparable from the network cable. Network lines are commonly used: twisted pair, coaxial cable, optical fiber and so on. Here, we twisted the performance indicators, the use of in-depth and detailed discussion:
1, twisted pair wire according to whether the external metal shield sub-sets: unshielded twisted pair (STP - shieldedTwistedpair) and unshielded twisted pair (UTP-unshieldedTwistedpair). Starting from the price, performance and maintainability, the majority of local area network using unshielded twisted pair (UTP).
2, divided by the electrical characteristics: the EIA/TIA-568 standard, according to electrical characteristics of the UTP is divided into 3 categories, Category 4, Category 5, Category 5e, Category 6, Category 7 cable, Category 5 the following twisted pair transmission has been rarely used slower,hollister store, and generally buy more than Category 5 cable. Category 5 maximum speed of 100M, 5 class line marked with CAT5 words, while the ultra-5e Category 5 line marked with the words. Network is the most commonly used three lines and five lines; 3 class lines in the line is two-on-four, Category 5 cable in the line is four pairs of eight.
3, Appearance: twisted pair from 8 species (orange and white, orange, green, white, blue, blue, green, brown white, brown) lines of different colors twisted together into 4 pairs. The role of twisted pairs to minimize electromagnetic radiation and external electromagnetic interference.
4, twisted pair connector: RJ-45 twisted pair crystal through the first access network equipment such as card or HUB. RJ-45 crystal head by a metal and plastic structure, making the required cable RJ-45 connector crystal concave front with 8 monks, referred to as Groove metal contacts total of 8, referred to as RJ-45 connector pin number is: When the metal face of our time; from left to right pin number followed by 1,2,3,4,5,6,vibram fivefingers,7,8. RJ-45 crystal head pin serial cable connection in the network is very important.
5, transfer targets: at least 0.6 m, the maximum transmission distance of 100 meters. Here is the card to 100 meters HUB, HUB or HUB to the distance between up to 100 meters. Of course, we can install the repeater between two twisted pair up to four repeaters can be installed; if the installation of four repeaters connected five segments,asics shoes, the maximum transmission distance up to 500 meters.
6, the connection standards: EIA / TIA cabling standards set forth in the twisted-pair sequence of two lines 568A and 568B.
568A standard:
green and white -1, Green -2, -3 orange and white, blue, -4, -5 blue, orange, -6, -7 brown white, brown -8
568B standard:
orange and white -1, orange, -2, -3 green and white, blue, -4, -5 blue, green, -6, -7 brown white, brown -8
(Note: 1,2,3,4,5,6,7,8 here is the RJ-45, respectively, crystal head pin numbers)
order to ensure the best compatibility, widely used EIA / TIA 568B standard to make the network cable. Of course, RJ-45 jack at each end of the network connection using either standard 568A or 568B standards are feasible in the network. But the twisted pair line ordering and RJ-45 crystal head of the pin number to one correspondence.
7, twisted pair of different production methods between devices.
MDI means that the mouth is level with mouth, MDI-X means that the port is the common port.
1) the connection between the NIC and HUB:
PC when the unit is connected to HUB, HUB to MDIX port, PC port for the MDI.
(1) 10Mbps network: as long as the cable is straight line can be, that correspond to the wire connections at both ends
(2) 100Mbps network: cable as straight lines, but also must follow the EIA / TIA 568A or 568B wiring standard criteria set forth in order to produce the line. 568A and 568B connected in the order given above. The following example is given to 568B standard network cable on both sides of the production method, refer to the following:
1 ------------ 1 orange and white orange and white
2 ------------ 2 orange orange
3 ------------ 3 green white green white
4 ------------ 4 Blue Blue
5 ------------ 5 blue blue
6 ------------ 6 Green Green
7 ------------ 7 brown white brown white
8 ------------ 8 brown brown
2) between the two HUB:
level during the HUB
even when the mouth should be level with the control switch on the MDI port on the HUB, which we call the Uplink port.
(1) If the HUB has Uplink port, then connected with straight lines.
(2) If no UPlink port HUB, or damaged beyond use, you must use the MDI-X cascade port. At this point must be twisted-pair cross, respectively, 1 and 3,2 and 6 will be cross-connections. Refer to the following:
TX + 1 ----- 3 RX +
TX-2 ------ 6 RX-
RX + 3 ---- 1 TX +
RX-6 ----- 2 TX-
3) between two computers connected to:
HUB
between the two methods is connected with the second case. 1 and 3,womens timberlands,2 and 6 is about cross-connections. See detailed above.
7, production of cable should should pay attention to the problems and techniques:
1) 10M Ethernet cable with numbered cores 1,2,3,6 transfer data, while the 100M network card to use four pairs of lines. Since 10M 100M network card can be used by way of making the cable; and has four pairs of twisted-pair cable also provided, so that the use of 10M cards, usually made by way of cable 100M.
2) commonly used in the 100M network EIA / TIA 568B standards; green across the blue line should be on the line. The easiest place to make a mistake here is to the white adjacent to the Green Line and Green Line together, the green line into the location of the first four pins; This will result in crosstalk, the transmission efficiency.
3) standard requirements of 1 and 2,3 and 6,4 and 5,7 and 8 wire must be twisted to. This data transmission can reduce and suppress outside interference. Improve the network transmission quality.
4) cross-over cable for connection ADSLMODEM and hubs HUB, HUB and HUB connection between the port is not connected through the class, and two computers connected to each other directly through the card. Making just the way 1-3,2-6 exchange, which is a use of 568B production, the other one produced using 568A.
5) in the 10M Ethernet, cable only numbered 1,2,3,6 wire transfer data. By this analysis, in the case of a particular order to improve the efficiency and savings on raw materials, it can also be an 8-core system using twisted pair cable as the two networks, that is, two closely spaced and workstations on the network if interference less demanding, we can be connected with a twisted pair of two workstations. We can also set the process in the LAN area, in order to save the wires, we can also use twisted-pair transmission HUB or switch the DC voltage used; of course, will have to 220V voltage transformer at one end and then the access network line.
above is my point in the formation of network experience, now and everyone a share. It is willing to build networks in the usual, can give you some guidance and by executing.

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