Introducing Cisco Data Center Networking (DCICN, legacy) — Question 25

Which two statements about PCIe are true? (Choose two.)

Answer options

• A. The PCIe link is built around dedicated unidirectional couples of serial, point-to-point connections known as lanes.
• B. You can install a PCI Express x8 adapter into an x4 slot.
• C. The PCIe standard is a bus-based system in which all the devices share the same bidirectional, 32-bit or 64-bit, parallel signal path.
• D. The PCIe 1.0 standard doubles the transfer rate compared to PCIe 2.0.
• E. A link that is composed of four lanes is called an x4 link.

Correct answer: A, E

Explanation

Option A is correct because PCIe indeed uses dedicated unidirectional connections called lanes. Option E is also correct as an x4 link is defined by having four lanes. Options B, C, and D are incorrect; B is false because an x8 adapter will not fit properly in an x4 slot, C is inaccurate since PCIe is not a bus-based system but a switched architecture, and D is wrong as PCIe 2.0 actually doubles the transfer rate of PCIe 1.0.