Lesson 2: Deploying Ethernet Cabling
BiDi (bidirectional)
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.
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.) RJ45 TERA GG45 Horizontal connectors
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 project manager is preparing a team to set up cabling infrastructure in a new building. Which of the following tools should they order to be able to create patch cords? Block tool Crimper/Cable stripper Punchdown tool Fusion Splicer
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. Many crimpers also come with cable stripping capabilities. 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 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 fusion splicer is a tool for joining strands of fiber optic cable with minimal signal loss. It is NOT used to create patch cords.
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? Crimper Punchdown tool Block tool 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 solutions architect is designing a cable management solution. Which of the following is the most common? Krone 110 block Patch panel 66 Block
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 project manager is putting together supplies for a project using fiber optic cabling. The manager is looking at the cabling core ferrule, which has the tightest connection and best return loss performance. Which of the following should the project manager use? APC UPC PC LC
APC
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? Riser Core Buffer 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 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? CWDM WDM BiDi DWDM
Coarse Wavelength Division Multiplexing (CWDM) supports up to 16 wavelengths and typically deploys four or eight bidirectional channels over a single fiber strand.
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? Backbone Horizontal cabling Telecommunications room 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.
DWDM (Dense Wavelength Division Multiplexing)
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 systems administrator is looking at technology in the organization's environment and finds Fast Link Pulse. What does this technology do? Does not support autonegotiation Supports up to 10 Mbps Typically deployed on new networks 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 project manager is preparing for an upcoming work assignment and is comparing available cable types for use within the project. What is NOT a benefit of using fiber optic cabling? Bandwidth Cost Interference Attenuation
Fiber optic cabling costs more than copper cabling. This is the main downside for organizations, as most organizations tend to go with the lowest cost options to support operations. Fiber optic cabling supports higher bandwidth over longer cable runs (measured in kilometers rather than meters). The electrical signals carried over the copper wire are subject to interference. Fiber optic signaling uses pulses of infrared light, which are not susceptible to interference. The electrical signals carried over copper wire are also subject to attenuation. Fiber optic signaling uses pulses of infrared light, which suffer less from attenuation.
A company calls a consultant to replace STP cabling and is looking at the varying types. Which of the following is the most challenging to install? S/FTP F/UTP Legacy STP ScTP
Legacy shielded twisted pair (STP) cable could be complex to install, as it requires bonding each element to ground manually. Using screened or shielded cable means the consultant must also use screened/shielded connectors. Modern shielded/foiled twisted pair (S/FTP) solutions also reduce this complexity by incorporating bonding within the design of each element. Modern foiled/unshielded twisted pair (F/UTP) solutions (using the appropriate cable, connectors, and patch panels) reduce this complexity by incorporating bonding within the design of each element. Screened cable has one thin outer foil shield around all pairs. Screened cable is usually designated as screened twisted pair (ScTP).
A network cabling operator is looking at different fiber optic connector form factors. Which of the following only works for multimode? ST SC MTRJ LC
Mechanical Transfer Registered Jack (MTRJ) is a small-form-factor duplex connector with a snap-in design used for multimode networks. Straight Tip (ST) is an early bayonet-style connector that uses a push-and-twist locking mechanism. Used mostly for multimode networks, ST is not widely used for Ethernet installations anymore. The Subscriber Connector (SC) is a push/pull design, allowing for simple insertion and removal. Technicians can use SC for single- or multimode. The Local Connector (LC) is a small-form-factor connector with a tabbed push/pull design. LC is similar to SC, but the smaller size allows for higher port density.
A cable operator is laying out unshielded twisted pair (UTP) cabling in an environment. Which of the following is not a consideration for UTP? Twisted to reduce interference Best used outside Uses solid cabling Measured in AWG
Most twisted pair cable used in office networks is unshielded twisted pair (UTP). Modern buildings are often flood-wired using UTP cabling. The pairs are twisted at different rates to reduce external interference and crosstalk. Crosstalk is a phenomenon whereby one pair causes interference in another as a result of their proximity. Solid cabling uses a single thick wire per conductor. The use of such cabling is for cables that run behind walls or through ducts. The American Wire Gauge (AWG) is the standard that measures copper wire thickness. Increasing AWG numbers represent thinner wires.
A network administrator is setting up cabling between buildings and needs to transmit the maximum distance possible. Which type of cabling would be most suitable? A.MMF B.SMF C.Twisted pair D.Coaxial
Single Mode (SMF) fiber optic cable supports higher bandwidth over longer links than copper cable. Single mode allows for longer distance transmission than MultiMode. MultiMode (MMF) fiber optic cable also supports higher bandwidth over longer links than copper cable. However, single mode would allow longer distances. Twisted pair is a type of copper cable that suffers from high attenuation, meaning that the signal quickly loses strength over long links. Coaxial is also a type of copper cable that suffers from high attenuation, meaning that the signal quickly loses strength over long links.
A network technician is researching standards for the physical and data link layer. Which standard, developed to implement the functions of the physical and data link layers of the OSI model, is the most important? A.802.3 B.802.1D C.802.11 D.802.1X
The most important standard developed is the Institute of Electrical and Electronics Engineers (IEEE) 802.3 Ethernet standards. Under the original 802.1D standard, this made the network unavailable for extended periods—tens of seconds—during configuration changes. The basis of most wireless LANs (WLANs) comes from the IEEE 802.11 standards, better known by its brand name Wi-Fi. The 802.11 standards define the physical layer media by which data encodes into a radio carrier signal. The IEEE 802.1X port-based Network Access Control (NAC) protocol provides the means of using an Extensible Authentication Protocol (EAP) method when a device connects to an Ethernet switch port, wireless access point, or virtual private network (VPN) gateway.
A network technician is laying out coax cables and needs to order more termination connectors. What should the technician order? F-type SFP+ DAC QSFP+ DAC RJ-11
The technician usually terminates coax cables using F-type connectors, which the technician secures by screwing into place. Coax cables are categorized using the Radio Grade (RG) standard. SFP+ Direct Attach Copper (DAC) can terminate Twinax for 10/40 GbE. Twinaxial (or twinax) is similar to coax but contains two inner conductors. QSFP+ Direct Attach Copper (DAC) can also terminate Twinax for 10/40 GbE. Technicians use twinax for data center 10 GbE (unofficially referred to as 10GBASE-CR) and 40 GbE (40GBASE-CR4). RJ-11 are smaller connectors used with 2- or 3-pair unshielded twisted pair (UTP). There is room for six wires, but the most commonly used are the four center wires.
A company is upgrading its current network infrastructure to Gigabit Ethernet. Which of the following about Gigabit Internet is true? (Select all that apply.) Works over Cat 5e or newer Max distance of 100 m for UTP cabling between node/switch port or between two ports Supports rates up to 1000 Mbps Specified as 100BASE-T
Top 3 correct 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.
WDM (wavelength division multiplexing)
Wavelength Division Multiplexing (WDM) is a means of using a strand to transmit or receive more than one channel at a time.
