CPCT Network Topology & Configuration 4 — Questions and Answers
Question 1: A technician is asked to install cabling for a new VoIP phone system. Which IEEE PoE standard delivers up to 30 watts per port to support mid-span powered devices?
- IEEE 802.3af (PoE)
- IEEE 802.3at (PoE+) (Correct answer)
- IEEE 802.3bt Type 3 (PoE++)
- IEEE 802.3bt Type 4 (PoE++)
Correct answer: IEEE 802.3at (PoE+)
IEEE 802.3at (PoE+) delivers up to 30 watts per port, compared to 802.3af's 15.4 watts, making it suitable for higher-power devices like VoIP phones with displays.
Question 2: In a hierarchical star (extended star) topology used in enterprise cabling, what is the role of the intermediate distribution frame (IDF)?
- It connects the building to the service provider's network
- It aggregates horizontal cabling from work areas on a floor and uplinks to the MDF (Correct answer)
- It terminates backbone fiber from multiple buildings
- It provides wireless access point connectivity only
Correct answer: It aggregates horizontal cabling from work areas on a floor and uplinks to the MDF
The IDF aggregates horizontal cabling runs from work area outlets on a given floor and connects via backbone cabling up to the main distribution frame (MDF).
Question 3: According to ANSI/TIA-568, what is the minimum bend radius allowed for a Cat 6 UTP cable during installation (under tension)?
- 1× the cable diameter
- 4× the cable diameter (Correct answer)
- 8× the cable diameter
- 10× the cable diameter
Correct answer: 4× the cable diameter
Under tension during installation, Cat 6 UTP must maintain a minimum bend radius of 4× the cable diameter to prevent damage to the cable's internal geometry.
Question 4: Which physical layer topology is used by legacy 10BASE5 Ethernet (Thicknet)?
- Ring
- Star
- Bus (Correct answer)
- Mesh
Correct answer: Bus
10BASE5 Thicknet uses a physical bus topology where all devices tap into a single shared coaxial cable segment.
Question 5: A technician is troubleshooting a network where multiple users lose connectivity simultaneously whenever there is a problem at one central location. Which topology does this describe?
- Ring topology
- Bus topology
- Star topology (Correct answer)
- Mesh topology
Correct answer: Star topology
In a star topology, all devices connect to a central switch or hub; failure of that central device causes all connected devices to lose connectivity.
Question 6: What is the maximum number of consolidation points (CPs) permitted in a single horizontal cabling channel according to TIA-568?
- One (Correct answer)
- Two
- Three
- No limit if total length is under 100m
Correct answer: One
TIA-568 permits only one consolidation point per horizontal cabling channel, used to transition between cable types such as from round to flat cable.
Question 7: When a CPCT technician installs a new network segment using 10GBASE-SR multimode fiber, which OM-rated fiber type provides the longest supported distance?
- OM1 (62.5/125 µm)
- OM2 (50/125 µm)
- OM3 (50/125 µm laser-optimized)
- OM4 (50/125 µm high-bandwidth) (Correct answer)
Correct answer: OM4 (50/125 µm high-bandwidth)
OM4 laser-optimized 50/125 µm multimode fiber supports 10GBASE-SR up to 400 meters, the longest distance among OM-rated multimode options.
CPCT Network Topology & Configuration 4
A technician is asked to install cabling for a new VoIP phone system.
Which IEEE PoE standard delivers up to 30 watts per port to support mid-span powered devices?