Networks and links continue to get speedier, but at some point, they require faster cabling to support them. You may need to upgrade copper to faster copper, copper to fiber or even older fibers to quicker ones. How well do you know the rules? Answers and explanations are in red.

1. That Cat 5e cable you installed a decade ago will still support network speeds of up to _________.
A. 100 megabits per second
B. 1 gigabit per second
C. 10 gigabits per second
D. 100 gigabits per second

Cat 5e was designed as an enhancement of Cat 5 to support 1 Gigabit Ethernet but not higher speeds.

2. In the United States, the highest performance standardized twisted-pair copper cable available is _________.
A. Cat 6
B. Cat 6a
C. Cat 7
D. Cat 7a

US TIA standards recognize Cat 6a, designed for 10 Gigabit Ethernet. Cat 7 is the name of the cable used in international standards for Class F cabling.

3. Users in the United States can choose to install _________ twisted-pair copper cable that meets standards.
A. Unshielded
B. Screened
C. Shielded
D. All of the above

U.S. standards are primarily based on UTP cable, but other types are allowed if they meet the same performance specifications.

4. Outside the United States, IEC/ISO standards recognize a higher performance cable called Class F that manufacturers in the United States sell as “Cat 7;” it is not a recognized U.S. standard.
True
False

Cat 7 is the name of the cable used in international standards for Class F cabling.

5. When upgrading a twisted-pair copper cabling system, you need to upgrade _________.
A. Only the permanent link
B. The permanent link and the punchdowns
C. The permanent link, the punchdowns and the patch panels
D. The permanent link, the punchdowns, the patch panels and the patchcords

Performance of any twisted pair copper cabling system is dependent on having every component in the system rated for the maximum speed.

6. Much of the multimode fiber installed in the United States is _________, which has been available for 25 years but does not support new networks well.
A. 62.5/125 (OM1)
B. 50/125 (OM2)
C. 50/125 (OM3)
D. 50/125 (OM4)

62.5/125 (OM1) fiber was almost exclusively used in the United States until 1 Gigabit Ethernet was introduced. Then 50/125 “laser rated” fiber became popular.

7. The most cost-effective upgrade for multimode fiber is _________, which will support networks up to 100 gigabits per second over 100 meters.
A. 50/125 (OM2)
B. 50/125 (OM3)
C. 50/125 (OM4)
D. Single-mode (OS1)

50/125 (OM3) fiber is most widely supported by networks today. OM4 fiber is still being considered for most networking standards.

8. For data centers upgrading for 100 gigabit links over multimode fiber, you must plan for _________.
A. 2 fibers per link
B. 4 fibers per link
C. 12 fibers per link
D. 24 fibers per link

Currently, 100 Gigabit Ethernet uses parallel transmission, 10 links of 10 gigabits per second, over 10 fibers in both directions. The connectors specified are 12 fiber connectors, so 24 fibers would be required.

9. For data centers upgrading to 100- gigabit links over single-mode fiber, you must plan for _________.
A. 2 fibers per link
B. 4 fibers per link
C. 12 fibers per link
D. 24 fibers per link

100 Gigabit Ethernet over single mode fiber uses wavelength-division multiplexing to send 10 signals at 10 wavelengths over a single fiber in each direction for two fibers.

10. Wireless access points can be connected over any cable, fiber or copper, that supports data rates of at least _________.
A. 100 megabits per second
B. 1 gigabit per second
C. 10 gigabits per second
D. 100 gigabits per second

The highest speed Wi-Fi wireless systems need only a 1 Gigabit Ethernet input.


HAYES is a VDV writer and educator and the president of The Fiber Optic Association. Find him at www.jimhayes.com.