2) Deploying Ethernet Cabling Flashcards
A network technician needs a cost-effective solution that can multiplex up to 16 wavelengths on an SFP/SFP+ interface. Which multiplexing technique should the network technician use?
A. CWDM
B. WDM
C. BiDi
D. DWDM
A. CWDM
Coarse Wavelength Division Multiplexing (CWDM) supports up to 16 wavelengths and typically deploys four or eight bidirectional channels over a single fiber strand.
Wavelength Division Multiplexing (WDM) is a means of using a strand to transmit or receive more than one channel at a time.
Bidirectional (BiDi) transceivers support, transmit, and receive signals over the same strand of fiber. This uses WDM to transmit the transmit (Tx) and receive (Rx) signals over slightly shifted wavelengths.
Dense Wavelength Division Multiplexing (DWDM) provisions a greater number of channels (20, 40, 80, or 160). This means that there is much less spacing between each channel and requires more precise and expensive lasers.
A project manager is ordering equipment to set up fiber cabling in a new building. Which of the following tools will allow a more permanent join with lower insertion loss?
A. Crimper
B. Punchdown tool
C. Block tool
D. Fusion splicer
D. Fusion splicer
A fusion splicer achieves a more permanent join with lower insertion loss (>=0.1 dB). The fusion splicing machine performs a precise alignment between the two strands and then permanently joins them together.
A cable crimper creates a patch cord that fixes a plug to a cable. The tools are specific to the type of connector and cable, although some have modular dies supporting a range of RJ-type plugs.
A punchdown tool terminates a fixed cable and fixes conductors into an IDC. There are different IDC formats (66, 110, BIX, and Krone) that require different blades.
A block tool terminates a group of connectors in one action. For a 110 format panel, there are four position blocks suitable for terminating 4-pair data cabling.
A systems administrator is looking at technology in the organization’s environment and finds Fast Link Pulse. What does this technology do?
A. Does not support autonegotiation
B. Supports up to 10 Mbps
C. Typically deployed on new networks
D. Sends link integrity test signals
D. Sends link integrity test signals
Fast Ethernet codes a 16-bit data packet into this signal to advertise its service capabilities. This is known as a Fast Link Pulse.
A node that does support autonegotiation can detect a node that does not support it, and it sends ordinary link integrity test signals or Normal Link Pulses.
The Fast Ethernet standard uses the same Carrier Sense Multiple Access with Collision Detection (CSMA/CD) protocol as 10BASE-T but with higher frequency signaling and improved encoding methods, raising the bit rate from 10 Mbps to 100 Mbps.
New networks would not deploy Fast Ethernet, but the sysadmin may need to maintain it in legacy installations.
A new network engineer is deploying an architecture using Carrier Sense Multiple Access with Collision Detection (CSMA/CD). How does the CSMA/CD protocol work?
A. Data, check network, transmit data, collision, retransmit
B. Data, transmit, collision, wait, retransmit
C. Data, check network, transmit data, collision, wait, retransmit
D. Data, check network, transmit data, collision, wait
C. Data, check network, transmit data, collison, wait, retransmit
The following steps are the correct order of a CSMA/CD protocol: Data, check network, transmit data, collision, wait, retransmit.
The steps of data, check network, transmit data, collision, and retransmit are missing the wait portion after a collision. If the protocol does not include a wait portion, then there would be many more collisions.
The steps of data, transmit, collision, wait, and retransmit are missing the check network. This is an important part of the CSMA/CD protocol.
The steps of data, check network, transmit data, collision, and wait are missing the retransmit portion. The retransmit portion is a crucial step. If it does not retransmit, it makes it pointless to do the other steps.
A company is upgrading its current network infrastructure to Gigabit Ethernet. Which of the following options concerning Gigabit Internet is true? (Select all that apply.)
A. Works over Cat 5e or newer
B. Max distance of 100 m for UTP cabling between node/switch port or between two ports
C. Supports rates up to 1000 Mbps
D. Specified as 100BASE-T
A. Works over Cat 5e or newer
B. Max distance of 100 m for UTP cabling between node/switch port or between two ports
C. Supports rates up to 1000 Mbps
Gigabit Ethernet works over Cat 5e or better. Gigabit Ethernet does not support hubs and implements using only switches.
The maximum distance of 100 meters (328 feet) applies to UTP cabling between the node and a switch port or between two switch ports.
Gigabit Ethernet builds on the standards defined for Ethernet and Fast Ethernet, implementing rates of 1000 Mbps (1 Gbps).
Over copper wire, the specification for Gigabit Ethernet is 1000BASE-T, not 100BASE-T as offered in the question. The number 1000 in 1000BASE-T correlates to the implementation rate of 1000 Mbps. Keep in mind that it can’t auto negotiate with older technologies, though.
A network technician is looking over diagrams for special types of equipment rooms that mark the point at which external cabling (located outside the plant) joins to internal cabling (located on the premises). What is this called?
A. Backbone
B. Horizontal cabling
C. Telecommunications room
D. Demarc
D. Demarc
Demarcs are special types of equipment rooms marking the point at which external cabling (located outside the plant) joins to the internal cabling (located on the premises).
Backbone cabling connects horizontal cross-connects (HCCs) to the main cross-connect (optionally via intermediate cross-connects). They are also known as vertical cross-connects.
Horizontal cabling connects user work areas to the nearest horizontal cross-connect. A cross-connect is also known as a distribution frame.
The telecommunications room houses horizontal cross-connects. Essentially, this is a termination point for the horizontal cabling along with a connection to backbone cabling.
A network technician in Germany is setting up Cat 7 cabling in the organization’s environment. The technician should, to comply with installation standards, terminate the cabling with what type of connector? (Select all that apply.)
A. RJ45
B. TERA
C. GG45
D. Horizontal connectors
B. TERA
C. GG45
TERA connectors, rather than standard RJ-45 connectors, can terminate Cat 7 cabling. TIA/EIA does not recognize Cat 7 but appears in the cabling standards created by the ISO (ISO/IEC 11801).
GG45 connectors, rather than standard RJ-45 connectors, can terminate Cat 7 cabling. Cat 7 cable is always of a screened/shielded type and rated for 10GbE applications up to 100 m (328 feet).
The technician cannot terminate Cat 7 cabling using the standard RJ-45 connectors. For faster network applications (Gigabit Ethernet and better), the performance of connectors becomes increasingly critical.
TIA/EIA standards recommend Cat 6A for use in health care facilities, with Power over Ethernet (PoE) 802.3bt installations, and for horizontal connections to wireless access points.
A technician who lays cabling is researching how the manufacturer constructed fiber optic cabling. Which of the following reflects signals back into the waveguide as efficiently as possible so that the light signal travels along the waveguide by multiple internal reflections?
A. Riser
B. Core
C. Buffer
D. Cladding
D. Cladding
Cladding reflects signals back into the waveguide as efficiently as possible so that the light signal travels along the waveguide by multiple internal reflections.
Riser cabling (in conduit or spaces such as lift shafts) should also conform to the appropriate fire safety standards. These are similar to the requirements for plenum spaces but not quite as strict.
Core provides the transmission path for the light signals (waveguide).
Buffer is a protective plastic coating. It may be of a tight or loose configuration, with the loose format using some form of lubricant between the strand and the sheath.
A solutions architect is designing a cable management solution. Which of the following is the most common wiring distribution?
A. Krone
B. 110 block
C. Patch panel
D. 66 Block
C. Patch Panel
A patch panel or patch bay is a type of distribution block with insulation-displacement connections (IDCs) on one side and pre-terminated RJ-45 modular ports on the other.
Where a 110 block uses a two-piece design and where a network administrator installs wafer blocks over the main block, the competing formats BIX and Krone use a single module.
The 110 block (developed by AT&T) is a type of distribution frame supporting 100 MHz operation (Cat 5) and better. A 110 wiring block is arranged horizontally rather than vertically.
A 66 block is an older-style distribution frame used to terminate telephone cabling and legacy data applications (pre-Cat 5). A 66 block comprises 50 rows of 4 IDC terminals.
A help desk operator is trying to identify the vendor for a piece of equipment. What could the help desk operator check to determine the vendor?
A. Last six digits of a MAC address
B. OUI
C. I/G bit of a MAC address
D. FCS
B. OUI
The first six hex digits of a MAC address (3 bytes or octets), also known as the Organizationally Unique Identifier (OUI), identifies the manufacturer of the adapter.
The last six digits of a MAC address are a serial number. An organization can decide to use locally administered addresses in place of the manufacturers’ universal coding systems.
The I/G bit of a MAC address determines whether the frame addresses an individual node (0) or a group (1). The latter is for broadcast and multicast transmissions.
The Cyclic Redundancy Check is also known as the Frame Check Sequence (FCS) and used in collision detection. There is no mechanism for retransmission if damage is detected.
