Certmaster learn network+ Exam N10-008 - Lesson 2: Deploying Ethernet Cabling

All network signaling uses electromagnetic radiation of one type or another. Electromagnetic radiation means

transmitting signals as electric current, infrared light, or radio waves.

Single Mode Fiber (SMF) has a small core

(8 to 10 microns) and a long wavelength, near infrared (1310 nm or 1550 nm) light signal, generated by a laser. There are two grades of SMF cable; OS1 is designed for indoor use, while OS2 is for outdoor deployment.

110 Block (110-Punchdown 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, offering better density than a 66 block.

These Ethernet media specifications are named using a three-part convention, which is often referred to as xBASE-y. This describes:

- The bit rate in megabits per second (Mbps) or gigabits per second (Gbps). - The signal mode (baseband or broadband). All mainstream types of Ethernet use baseband transmissions, so you will only see specifications of the form xBASE-y. - A designator for the media type.

BIX and Krone Distribution Frames Where a 110 block uses a two-piece design where wafer blocks are installed over the main block, competing formats BIX and Krone use a single module

110 blocks and BIX blocks (developed by Nortel) are common in North America, while some European vendors often prefer Krone.

Gigabit Ethernet does not support hubs; it is implemented only using switches. The maximum distance of

100 m (328 feet) applies to 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 to implement rates of

1000 Mbps (1 Gbps). Over copper wire, Gigabit Ethernet is specified as 1000BASE-T, working over Cat 5e or better

The most important of these protocols, standards, and products are the Institute of Electrical and Electronics Engineers (IEEE)

802.3 Ethernet standards ( ieee802.org/3 ).

OM3/OM4-these are also 50-micron cable, but manufactured differently, designed for use with 850 nm Vertical-Cavity Surface-Emitting Lasers (VCSEL), also referred to as laser optimized MMF (LOMMF).

A VCSEL is not as powerful as the solid-state lasers used for SMF, but it supports higher modulation (transmitting light pulses rapidly) than LED-based optics.

S/FTP

A braid screen shields the entire cable; foil shields each wire pair inside

Using connectors does reduce the overall performance of the cable. Each connector will "cost" a certain amount of insertion loss (typically budgeted as 0.5 dB) and reflection loss

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 using an arc weld.

PBX (private branch exchange)

A telephone switch used to connect and manage an organization's voice calls.

Copper wire thickness is measured using

American Wire Gauge (AWG). Increasing AWG numbers represent thinner wire. Solid cable uses thicker 22 to 24 AWG, while the stranded cable used for patch cords is often 26 AWG

The Ethernet protocol governing contention and media access is called

Carrier Sense Multiple Access with Collision Detection (CSMA/CD).

backbone cabling

Connects horizontal cross-connects (HCCs) to the main cross-connect (optionally via intermediate cross-connects).

horizontal cabling

Connects user work areas to the nearest horizontal cross-connect. A cross-connect can also be referred to as a distribution frame. Horizontal cabling is so-called because it typically consists of the cabling for a single floor and so is made up of cables run horizontally through wall ducts or ceiling spaces.

Fiber optic signaling uses pulses of infrared light, which are not susceptible to interference, cannot easily be intercepted, and suffer less from attenuation.

Consequently, fiber optic cabling supports higher bandwidth over longer cable runs (that can be measured in kilometers, rather than meters).

A single optical fiber is constructed from three elements:

Core provides the transmission path for the light signals (waveguide). Cladding reflects signals back into the waveguide as efficiently as possible so that the light signal travels along the waveguide by multiple internal reflections. The core and cladding can be made from glass or plastic. The cladding is applied as a thin layer surrounding the core. Buffer is a protective plastic coating

Twisted pair can use either

solid or stranded conductor wires

10BASE-T Ethernet specifies that a node should transmit regular electrical pulses when it is not transmitting data to confirm the viability of the link.

Fast Ethernet codes a 16-bit data packet into this signal advertising its service capabilities. This is called a Fast Link Pulse. A node that does not support auto-negotiation can be detected by one that does and can send ordinary link integrity test signals or Normal Link Pulses.

100BASE-TX refers to

Fast Ethernet working over Cat 5 (or better) twisted pair copper cable with a maximum supported link length of 100 meters (328 feet).

Gigabit Ethernet is the mainstream choice for new installations of access networks; that is, cabling to connect client workstations to a local network.

Fiber gives better upgrade potential in the future, while copper cable is cheaper to install and far more hosts are installed with network cards that support copper than support fiber.

F/UTP

Foil over twisted-pair cabling (better security, noise immunity for EMI) It minimizes signal leakage and provides noise immunity from EMI

telecommunications room

Houses horizontal cross-connects. Essentially, this is a termination point for the horizontal cabling along with a connection to backbone cabling. An equipment room is similar to a telecommunications room but contains the main or intermediate cross-connects. Equipment rooms are also likely to house "complex" equipment, such as switches, routers, and modems.

Fiber is often used for backbone cabling in office networks and for workstations with high bandwidth requirements, such as video editing. The principal applications of 10 GbE (and better) are

Increasing bandwidth for server interconnections and network backbones, especially in datacenters and for storage area networks (SAN). Replacing existing switched public data networks based on proprietary technologies with simpler Ethernet switches (Metro Ethernet).

In basic operation modes, each fiber optic strand can only transfer light in a single direction at a time. Therefore, multiple fibers are often bundled within a cable to allow simultaneous transmission and reception of signals or to provide links for multiple applications.

Kevlar (Aramid) strands and sometimes fiberglass rods (strength members) are often used to protect the fibers from excessive bending or kinking when "pulling" the cable to install it

Fiber optic can be installed in the same topology as copper cable using distribution frames and switches

Long distance cables are typically laid as trunks or rings with repeaters or amplifiers between cable segments to strengthen the signal.

The attenuation of stranded wire is higher than solid wire, so it cannot be used over extended distances.

Most twisted pair cable used in office networks is unshielded twisted pair (UTP).

OM1/OM2-62.5-micron cable is OM1, while early 50-micron cable is OM2.

OM1 and OM2 are mainly rated for applications up to 1 Gbps and use LED transmitters.

MMF is graded by Optical Multimode (OM) categories, defined in the ISO/IEC 11801 standard:

OM1,2,3,4

Carrier Sense Multiple Access with Collision Detection (CSMA/CD) works to prevent collisions by

On detecting a collision, the node broadcasts a jam signal. Each node that was attempting to use the media then waits for a random period (backoff) before attempting to transmit again.

MMF uses less expensive optics and consequently is less expensive to deploy than SMF. However, it does not support such high signaling speeds or long distances as single mode and so is more suitable for LANs than WANs.

Optical transceivers for SMF are now only slightly more expensive than ones for MMF. Consequently, SMF is often used for short range applications in datacenters, as well as for long distance links. SMF still comes at a slight price premium, but it provides better support for 40 Gbps and 100 Gbps Ethernet standards.

Normally, strands are installed in pairs (duplex) at each device, with one strand for transmit (Tx) and one strand for receive (Rx)

Patch cables for fiber optic can come with the same connector on each end (LC-LC, for instance) or a mix of connectors (LC-SC, for instance).

he core of a fiber optic connector is a ceramic or plastic ferrule that holds the glass strand and ensures continuous reception of the light signals. The tip of the ferrule can be finished in one of three formats

Physical Contact (PC) UltraPhysical Contact (UPC)- Angled Physical Contact (APC)

40GBASE-T

S/FTP (Cat 8) 30 m (100 feet)

Fiber optic cabling is divided into

Single Mode (SMF) and MultiMode (MMF) types, and MMF is categorized by Optical Mode designations (OM1, OM2, OM3, and OM4).

Historically, transceiver modules were based on the Gigabit Interface Converter (GBIC) form factor, which used SC ports and was designed (as the name suggests) for Gigabit Ethernet. GBIC was very bulky and has largely been replaced by

Small Form Factor Pluggable (SFP), also known as mini-GBIC. SFP uses LC connectors and is also designed for Gigabit Ethernet. Enhanced SFP (SFP+) is an updated specification to support 10 GbE but still uses the LC form factor.

entrance facilities/demarc

Special types of equipment rooms marking the point at which external cabling (outside plant) is joined to internal (premises) cabling.

Mechanical Transfer Registered Jack (MTRJ) is a

a small-form-factor duplex connector with a snap-in design used for multimode networks.

Each conductor in a 4-pair data cable is color-coded. Each pair is assigned a color (Blue, Orange, Green, or Brown). The first conductor in each pair has a predominantly white insulator with strips of the color; the second conductor has an insulator with the solid color. The ANSI/TIA/EIA 568 standard defines two methods for terminating Ethernet connectors: T568A and T568B.

T568A is mandated by the residential cabling standard (TIA 570), but T568B is probably the more widely deployed of the two.

Angled Physical Contact (APC)-

The faces are angled for an even tighter connection and better return loss performance. APC cannot be mixed with PC or UPC. These connectors are usually deployed when the fiber is being used to carry analog signaling, as in Cable Access TV (CATV) networks. They are also increasingly used for long distance transmissions and for Passive Optical Networks (PON),

Physical Contact (PC)

The faces of the connector and fiber tip are polished so that they curve slightly and fit together better.

Work area

The space where user equipment is located and connected to the network, usually via a wall port.

Twisted pair copper cabling uses Registered Jack (RJ) connectors for the physical interface. RJ-45 connectors are used with 4-pair (8-wire) cables. The connectors are also referred to as 8P8C, standing for 8-position/8-contact.

This means that all eight "potential" wire positions are supplied with contacts, so that they can all carry signals if needed.

UltraPhysical Contact (UPC)

This means the cable and connector are polished to a higher standard than with PC.

Patch Panel/Patch Bay In data networks, numerous moves, adds, and changes (MACs) would require reterminating the wiring.

To simplify MACs, a patch panel or patch bay is a type of distribution block with IDCs on one side and pre-terminated RJ-45 modular ports on the other. This allows incoming and outgoing connections to be reconfigured by changing the patch cable connections, which is much simpler than reterminating punchdown blocks.

The smaller RJ-11 connectors are used with 2- or 3-pair UTP. There is room for six wires, but the four center wires are most commonly used RJ-11 connectors are used for telephone systems-for example, to connect a modem to a phone jack. An RJ-11 connector has only two contacts (6P2C).

Typically, the innermost pair, wired to pins 3 and 4, carries the dial tone and voice circuit. These are also called the Tip and Ring wires after the way older phone plugs were wired. The other pair is usually unused but can be deployed for a secondary circuit.

Specification, Cable, Max Distance 10GBASE-T

UTP (Cat 6) - 55 m (180 feet) F/UTP (Cat 6A) - 100 m (328 feet) S/FTP (Cat 7) - 100 m (328 feet)

UTP

Unshielded twisted pair. Cable type used in networks that do not have any concerns over EMI (electric magnetic interference), RFI(radio freq. interference), or cross talk. If these are a concern, STP is used.

Each network node connected to the same media is in the same collision domain. When

When two nodes transmit at the same time, the signals are said to collide and neither signal can reach its destination. This means that they must be resent, reducing available bandwidth

a punchdown block is comprised of

a large number of insulation displacement connection (IDC) terminals. The IDC contains contacts that cut the insulation from a wire and hold it in place.

The collision detection mechanism means that only half-duplex transmission is possible. This means that

a node can transmit or receive, but it cannot do both at the same time.

The more bandwidth available in the media, the greater the

amount of data that can be encoded.

Straight Tip (ST) is

an early bayonet-style connector that uses a push-and-twist locking mechanism. ST was used mostly for multimode networks, but it is not widely used for Ethernet installations anymore.

a 66 block

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. The 25-pair cable from the access provider is terminated on one side of the block.

The electromagnetic radiation forms a carrier wave with a given bandwidth or range of frequencies. A signal is transmitted over the wave

by modulation and encoding schemes

A patch cord is created using a

cable crimper - Tool to join a network jack to the ends of network patch cable.

Permanent cables are run through conduit to wall ports at the client access end and a fiber distribution panel at the switch end. Fiber patch cables are used t

complete the link from the wall port to the NIC and from the patch panel to the switch port.

Twinaxial (or twinax) is similar to coax but contains two inner conductors. Twinax is used for

datacenter 10 GbE (unofficially referred to as 10GBASE-CR) and 40 GbE (40GBASE-CR4) interconnects of up to about 5 meters for passive cable types and 10 meters for active cable types.

Fiber optic media can support higher bandwidths over longer distances than copper wire. These advantages make it a popular choice for

for long-distance telecommunications networks and for reliable, high-speed networking within datacenters.

Multimode Fiber (MMF)

has a larger core (62.5 or 50 microns) and shorter wavelength light (850 nm or 1300 nm) transmitted in multiple waves of varying length.

The narrow definition of bandwidth is a frequency range measured in

in cycles per second or Hertz (Hz), but the term is very widely used in data networking to mean the amount of data that can be transferred, measured multiples of bits per second (bps).

Wavelength Division Multiplexing (WDM)

is a means of using a strand to transmit and/or receive more than one channel at a time.

The Subscriber Connector (SC)

is a push/pull design, allowing for simple insertion and removal. It can be used for single- or multimode. It is commonly used for Gigabit Ethernet.

The Local Connector (LC) (also referred to as Lucent Connector)

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. LC is a widely adopted form factor for Gigabit Ethernet and 10/40 GbE.

Fiber optic cables are specified using the

mode, composition (glass/plastic), and core/cladding size; for example, 8.3 micron core/125 microcladding single mode glass

Coaxial (or coax) cable is made of

of two conductors that share the same axis, hence the name ("co" and "ax"). The core conductor of the cable is made of copper wire (solid or stranded) and is enclosed by plastic insulation (dielectric). A wire mesh (the second conductor), which serves both as shielding from EMI and as a ground, surrounds the insulating material. A tough plastic sheath protects the cable

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.

Dense Wavelength Division Multiplexing (DWDM)

provisions greater numbers 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.

Fixed cable is terminated using a

punchdown tool. This tool fixes conductors into an IDC. There are different IDC formats (66, 110, BIX, and Krone), and these require different blades.

Fiber optic cables fall into two broad categories:

single mode and multimode.

Fiber optic connectors are available in many different form factors

straight tip, subscriber connector, local connector, and mechanical transfer registered jack

Bidirectional (BiDi) transceivers (Bidirectional wavelength division multiplexing (WDM))

support transmit and receive signals over the same strand of fiber BiDi transceivers must be installed in opposite pairs, so the downstream transceiver would have to use 1490 nm for Tx and 1310 for Rx.

Coarse Wavelength Division Multiplexing (CWDM)

supports up to 16 wavelengths and is typically used to deploy four or eight bidirectional channels over a single fiber strand.

Twisted pair is a type of copper cable that has been extensively used for

telephone systems and data networks. One pair of insulated wires twisted together forms a balanced pair. The pair carry the same signal but with different polarity; one wire is positive, and the other is negative.

Quad small form-factor pluggable (QSFP) is a transceiver form factor

that supports 4 x 1 Gbps links, Enhanced quad small form-factor pluggable (QSFP+) is designed to support 40 GbE by provisioning 4 x 10 Gbps links.

Ethernet is a multiple access area network, which means that

the available communications capacity is shared between the nodes that are connected to the same media.

Media access control (MAC) refers to

the methods a network technology uses to determine when nodes can communicate on shared media and to deal with possible problems, such as two devices attempting to communicate simultaneously.

frequency

the rate at which a vibration occurs that constitutes a wave, either in a material (as in sound waves), or in an electromagnetic field (as in radio waves and light), usually measured per second.

equipment room

the room where main telephone and data lines enter the structure and connect to riser shafts within the building (also called data closet or terminal closet) An equipment room is similar to a telecommunications room but contains the main or intermediate cross-connects. Equipment rooms are also likely to house "complex" equipment, such as switches, routers, and modems.

Copper cable is used to transmit electrical signals. There are two main types of copper cable:

twisted pair and coaxial (coax). Copper cable suffers from high attenuation, meaning that the signal quickly loses strength over long links.

For this application, coax is usually terminated

using F-type connectors, which are secured by screwing into place.

copper wiring is terminated

using a distribution frme or a punchdown block

Fiber optic cable carries

very high frequency radiation in the infrared light part of the electromagnetic spectrum. The light signals are also not susceptible to interference or noise from other sources and less affected by attenuation. Consequently, fiber optic cable supports higher bandwidth over longer links than copper cable

A plenum space is a

void in a building designed to carry heating, ventilation, and air conditioning (HVAC) systems.

Unlike a hub, each switch port is a separate collision domain. By eliminating the effect of contention, switches allow for full-duplex transmissions,

where a node can transmit and receive simultaneously, and each node can use the full 100 Mbps bandwidth of the cable link to the switch port.

Ethernet dominates the wired LAN product market. Its popularity is largely based on its ease of installation and upgradability.

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