ccna 200-301 network simulator toolstation voucher

ccna 200-301 network simulator toolstation voucher.Pin 6 Receive -Pin 7 Not usedPin 8 Not usedCurrently, the T568B standard is commonly used in China. It is important to emphasize here that the wire sequence cannot be changed at will. For example, from the above connection standard, 1 and 2 are a pair of wires, while 3 and 6 are another pair of wires. However, if the above specified wire order is messed up, for example, if 1 and 3 are used as a transmitting pair and 2 and 6 are used as a receiving pair, then the interference immunity of these connecting wires will be reduced and the BER may increase, which will not guarantee the normal operation of Ethernet.Depending on the application, there are 3 types of twisted pair wires: straight-through, crossover, and all-inverse.. Straight-through line (Straight-through) o twisted-pair cable ends into the RJ-45 (crystal head) of the same line sequence, the domestic use is mostly T568B. This line is mainly used for the interconnection of different kinds of equipment, such as a computer a switch, computer a hub, switch a router, etc.. Here we have to emphasize that the computer and router belong to the same kind of equipment, hub and switch belong to the same kind of equipment, that is, between the computer and router, hub and switch can not use straight through twisted pair cable connected, because they are the same kind of equipment.. Crossover (Crossover). The two ends of a twisted pair cable are connected to the RL45 in different sequences, keeping the T568B sequence on one end and using the T568A standard on the other (that is, swapping 1 and 3, 2 and 6 in the T568B standard). Some people may wonder why only 4 of the 8 wires in a twisted pair are crossed. Although there are 8 twisted pairs, but in the case of low demand, the real data transmission of only 1, 2, 3, 6, 4 wires, the remaining 4, 5, 7, 8, 4 wires mainly play a secondary role such as shielding. This is also we often find that some projects only a twisted pair access, computers and telephones can be used at the same time, this is because the construction staff for convenience, cutting corners, the twisted pair in the unused 4 diverted out of 2 to the telephone. Crossover cable is mainly used for the interconnection of the same kind of equipment, such as a computer, a router, a router, a hub, a hub. It is particularly noteworthy that "computer-to-router" also uses crossover cables, because the hardware composition of the router and the computer is almost identical, and the computer can be used as a router, Windows Server 2000/2003/2008 also supports a variety of dynamic routing protocols, in addition Windows Server 2000/2003/2008 also supports a variety of dynamic routing protocols, in addition, "hub-and-switch" also uses this cable. The pins of the interface cards of the same device serve the same purpose, so if you use straight-through cables to connect the same device, both ends will be the sending end or both ends will be the receiving end, and data transmission will fail.. All-inverting line (Rollover). The two ends of the all-inverse line into the RJ-45 wire sequence is exactly opposite, this line is mainly used for the initial configuration of routers and switches for use, and sometimes used for asynchronous transmission.It is worth noting that with the development of technology, some new switches or routers can now automatically recognize the type of device connected and adjust the interface state to automatically adapt to the type of cable. However, in the CCNA exam, devices that support smart interfaces are not used by default and must meet the requirement of using crossover cables for the same type of device and straight-through cables for different devices.13 A