Straight through and Crossover Cables-
While discussing pin connectivity of LAN Cables, we generally come across queries on the difference between Straight-through and Crossover LAN Cables. Infact many times end to end connectivity fails when the correct type of cable is not used. Below detail will try to share some insight into both the Straight-Through and Crossover cable types :
Straight-Through Wired Cables –
Straight-Through cables are those which have pin assignments on each end of the cable. In other words Pin 1 connector A goes to Pin 1 on connector B, Pin 2 to Pin 2 and so on. Straight-Through wired cables are most commonly used to connect a host to a client or in other words between DCE and DTE equipment.
When we talk about patch cables (Cat5, Cat6, Cat6A etc.), the Straight-Through wired patch cable is used to connect computers, printers and other network client devices to the router switch or hub.
Straight Cable is the most common type in LAN and WAN IT Networking.Below is the pin connectivity of Straight-Through Cable across its both ends –
Crossover Wired Cables –
Crossover Cables are very much like Straight-Through cables with the exception that TX and RX lines are crossed (they are at opposite positions on either end of the cable).
Crossover cables are more commonly used to connect a computer to a computer or 2 or more switches together and maybe a little harder to find since they aren’t used nearly as much as straight-through cables.
The rationale behind Crossover Cable is since different devices TX and RX and different pins (i.e. DCE and DTE devices send and receive data on different ports.
Switches and hubs send data on pins 3+6 and receive on pins 1+2, whereas PCs, routers and WAPs send on 1+2 and receive on 3+6.
Below is the pin connectivity of Crossover Cable across its both ends –
It is important to share the conditions where Straight-Through and where Crossover Cable is required as per below-given table –
Download the comparison table here.
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