If the devices below were connected with UTP Ethernet cables, which pairs of devices would require a straight-through cable? (Choose two answers.)

(A) Router and PC
(B) Switch and PC
(C) Hub and switch
(D) Router and hub

Answer:

B and D are the correct answers. Straightthrough cable is a type of twisted-pair copper wire cable for local area network (LAN) use for which the RJ-45 connectors at each end have the same pinout. Straight-through cables are used to connect computers and other end-user devices e.g. printers to networking devices such as hubs and switches. Routers, wireless access point Ethernet ports, and PC NICs all send using pins 1 and 2, whereas hubs and LAN switches transmit on pins 3 and 6. Straight-through cables connect devices that use opposite pin pairs for sending because the cable does not need to cross the pairs.