A REPORT ON

CABLES AND THEIR TYPESBY

Mr. Aliasgar S K Mr. Mohamed Nabil Mr. Ayush Agrawal

2008A8PS044U 2008A1PS320U 2008A7PS105U

EIE CHEM C. SC.

AT Emirates Office Systems & Supplies (EOSS) Abu Dhabi, U.A.E

A Practice School I Station of

BITS, Pilani - Dubai Dubai International Academic City (DIAC) Dubai, U.A.E (JUNE 2010 - JULY 2010)

A REPORT ON

CABLES AND THEIR TYPESBY

Mr. Aliasgar S K Mr. Mohamed Nabil Mr. Ayush Agrawal

2008A8PS044U 2008A1PS320U 2008A7PS105U

EIE CHEM C. SC.

Prepared in Partial Fulfillment of the Practice School I Course AT Emirates Office Systems & Supplies (EOSS) Abu Dhabi, U.A.E A Practice School I Station of

BITS, Pilani - Dubai Dubai International Academic City (DIAC) Dubai, U.A.E (JUNE 2010 - JULY 2010)

BITS, Pilani - Dubai Dubai International Academic City (DIAC) Dubai, U.A.E Station: Emirates Office Systems & Supplies Dhabi Duration: 06.06.2010 to 29.07.2010 Date of Submission: 29.07.2010 Title of the Project: Cables and its Types ID No. / Name of the student: Aliasgar S. K. 2008A8PS044U. Mohamed Nabil 2008A1PS320U Ayush Agrawal 2008A7PS105U Discipline of Students: EIE / CHEM / CS Name and Designation of Experts: Mr. Elie Maidaa: Sales Engineer Mr. Barham: Chief Site Engineer (AFOC project) Mr. Ayman, Mr. Jawad, Mr. Mohammed: Site Engineers Name of the PS Faculty: Mr. Jaffer Shariff Key Words: Cables, Coaxial, Twisted Pair, Fiber optics, Transmission, Communication Project Areas: Coaxial cables, Twisted Pair cables, Fiber Optic cables Abstract:This report deals with cables and their different types. The major subcategories of cables are 1. Co-axial, 2. Twisted pair and 3. Fiber optic. This report discusses the major types of each cable along with their general characteristics and specifications along with the advantages and disadvantages of each cable. The different uses of each cable and their area of use is discussed. Each different cable and its termination along with the connectors used is further explained.

Location: Abu

Date of Start: 06.06.2010

Signature of the Students: Faculty:Aliasgar S. K. Mohamed Nabil (2008A8PS044U)

Signature of PS

Mr. Jaffer Shariff (2008A1PS320U)

Date: 28.06.2010

Ayush Agrawal (2008A7PS105U)

Date: 28.06.2010ACKNOWLEDGEMENTS Firstly, we would like to express my heartfelt gratitude to Dr. M. Ramachandran, Director BPD who has given us an opportunity to apply and understand our engineering concepts in a practical atmosphere. We are grateful to Mr. Elie Maidaa, Sales Engineer, for assisting us by providing the required information about the organization and for helping and guiding us throughout our project. Also, we would like to thank Engineer Barham, Site Engineer of AFOC project, for helping and guiding us throughout our project. Our sincere gratitude to Mr. Jaffer Shariff, our PS Faculty, for providing us with all the assistance required for successful completion of this report We would also like to thank Dr. Tanmay Panda, Dean (Placement & Practice School), for giving us this opportunity to work and apply our knowledge in the technical field and gain firsthand experience. Signature of students:

Aliasgar S. K. (2008A8PS044U)

Mohamed Nabil (2008A1PS320U)

Ayush Agrawal (2008A7PS105U) CONTENTS Abstract Acknowledgement Table of contents List of Figures Figure 1.6 - ISO 9001 Certificate................................................................................................ Figure 2.2.1 Cross Sectional View........................................................................................... Figure 2.2.2 Coaxial Cable with foil shield................................................................................. Figure 2.2.4.1 RCA Connector................................................................................................. Figure 2.2.4.2 BNC Connector.................................................................................................... Figure 2.2.4.3 - F-Pin Connector................................................................................................. Figure 2.2.5 - Different Cable Types........................................................................................... Figure 2.2.8 - Coaxial Cable........................................................................................................ Figure 2.3.1.1 - 25-pair color code Chart.................................................................................... Figure 2.3.1.2 Twisted Cable................................................................................................... Figure 2.3.2.1 Unshielded Twisted Pair................................................................................... Figure 2.3.2.2 UTP................................................................................................................... Figure 2.3.3.1 STP.................................................................................................................... Figure 2.3.4.1 RJ connections.................................................................................................. Figure 2.3.4.2 Terminated Cable.............................................................................................. Figure 2.4.1 Light in Fiber Optic Cable................................................................................... Figure 2.4.3.1 Cross-section view of Fiber cables................................................................... Figure 2.4.4.1 Table Types of jacket material.......................................................................... Figure 2.4.7.1 Total Internal Reflection................................................................................... 11 13 15 17 18 19 21 23 25 26 27 27 31 32 33 37 38 39 40

Figure 2.4.8.1 Transmission through MMF............................................................................. Figure 2.4.8.2 Cross section of SMF........................................................................................ Figure 2.4.9.1 Process Diagram of Manufacture of Fiber....................................................... Figure 2.4.11.1 Connectors..................................................................................................... Figure 2.4.12.1 Fiber Networks............................................................................................... List of tables

41 43 44 47 48

Table 1.3.1 - Principle Products..........................................................................................................5 Table 1.3.2 - Major Projects..............................................................................................................10 Table 2.3.3.1 Table for Data speeds...............................................................................................28 Table 2.3.4.1 Color Code...............................................................................................................33

CHAPTER 11.1

AN OVERVIEW OF THE COMPANY1

INTRODUCTION .......... 1.1.1 ABOUT 1 EOSS................................................................................................................. ............... 1.1.2 MISSION 2 STATEMENT....................................................................................................... .......... 1.2 PROFESSIONAL SERVICES....................................................................................... .......................... 1.2.1 IT & TELECOM OUTSOURCING & RECRUITMENT................................................................... 1.2.2 STRUCTURED CABLING .......... 1.2.3 PREMISES ACCESS CONTROL AND SECURITY. .............. 1.2.4 WIRELESS SYSTEMS ............... 1.2.5 OFFICE AUTOMATION AND ELECTRONICS ........... 1.3 PRINCIPLE PRODUCTS .. ................ 1.4 CLIENT BASE........ 2 3 3 3 3 5 6 2

...... 1.4.1 GOVERNMENT SECTOR........... 1.4.2 OIL AND GAS SECTOR . ............ 1.4.3 IT / SYSTEM INTEGRATORS ... ............ 1.4.4 UTILITIES AND INSTITUTION .. ........ 1.4.5 ELECTRO-MECHANICAL CONTACTORS........ ...... 1.5 MAJOR PROJECTS........ ....... 1.6 CERTIFICATION ................

6 6 6 7 8 9 11

CHAPTER 22.1

CABLES AND ITS TYPES12

INTRODUCTION .............. 2.2 CO-AXIAL CABLE.............................................................................................................. ................... 2.2.1 INTRODUCTION... ................................................ 2.2.2 DESCRIPTION....... ............. 2.2.2.1 CENTER CONDUCTOR..................................................................................................... ... 2.2.2.2 DIELECTRIC INSULATOR.................................................................................................... 2.2.2.3 BRAIDED SHEILD.............................................................................................................. ... 2.2.2.4 FOIL SHIELD.............................................................................................................. ........... 2.2.2.5 OUTER 13 14 14 14 15 16 16 13

JACKET.............................................................................................................. ...... 2.2.3 CHARACTERISTICS............................................................................................ ......................... 2.2.3.1 IMPEDANCE....................................................................................................... ................... 2.2.3.2 ATTENUATION................. .................................. ................. ................. .......... ................... 2.2.3.3 VELOCITY OF PROPAGATION................. ................. ................. ................. .................... 2.2.3.4 SHIELDING PERCENTAGE................. ................. ................. ................. .......................... 2.2.3.5 AMERICAN WIRE GAUGE................. ................. ................. ................. ............................ 2.2.4 CONNECTORS................. ................. ................. ................. ................. ......... ........ ................. 2.2.4.1 RCA................. ................. ................. ................. ................. ................. ....... .................... 2.2.4.2 BNC................. ................. ................. ................. ................. ................. ....... .................... 2.2.4.3 FPIN................. ................. ................. ................. ................. ................. ........ .................. 2.2.5 TYPES OF COAXIAL CABLES.......... 2.2.5.1 RG58.. ........ 2.2.5.2 RG59.. ........ 2.2.5.3 RG6.. ....... 2.2.6 ADVANTAGES & 21 DISADVANTAGES.............. 2.2.6.1 21 ADVANTAGES....... ................ 19 19 19 20 16 16 16 16 17 17 17 17 18 19

2.2.6.2 DISADVANTAGES.... ................ 2.2.7 FIBER, COAX OR UTP?............................................................................................................. 2.2.7.1 COST CONSIDERATION...................................................................................... .............. 2.2.7.2 SIZE......................................................................................................... ............................ 2.2.7.3 DISTANCE................................................................................................ ........................... 2.2.8 USES.... .............. 2.3 TWISTED PAIR CABLE .. .......... 2.3.1 GENERAL OVERVIEW. ............. 2.3.2 UNSHIELDED TWISTED PAIR.. ....... 2.3.2.1 UTP APPLICATIONS.. ............... 2.3.2.2 CABLE CATEGORIES.. ............. 2.3.2.3 COMMONLY USED UTP CABLES.. ........... 2.3.3 SHIELDED TWISTED PAIR. .............. 2.3.4 TERMINATION. ............ 2.3.5 ADVANTAGES & DISADVATAGES............. 2.3.5.1 ADVANTAGES OF TWISTED PAIR............... 2.3.5.2 DISADVANTAGES OF TWISTED PAIR............. 2.3.6 SAME CONCERNS.

22

22 22 23 23

23

25 25 27 28 28 28 30 32 34 34 34 35

............ 2.3.6.1 ELECTRONIC NOISE................ 2.3.6.2 THERMAL NOISE.............. 2.3.6.3 SHOT NOISE........... 2.3.6.4 FLICKER NOISE............. 2.3.6.5 BURST NOISE......... 2.3.6.6 AVALANCHE NOISE................. 2.3.6.7 CROSSTALK.......... 2.3.6.8 ELECTROMAGNETIC INTERFERENCE... ........ 2.3.6.9 FIRE SAFETY CONCERNS... .......... 2.3.6.9.1 PASSIVE FIRE PROTECTION........................ ............ 2.4 FIBER OPTIC CABLES .. ........... 2.4.1 DESCRIPTION............................................................................................... ............................... 2.4.2 HISTORY....................................................................................................... ................................ 2.4.3 CABLE TYPES........................................................................................................... ................... 2.4.4 JACKET MATERIAL..................................................................................................... ................. 2.4.5 WORKING OF FIBER OPTIC....................................................................................................... 2.4.6 REFRACTION INDEX........................................................................................................... ........ 2.4.7 TOTAL INTERNAL

35 35 35 35 35 36 36 37 37 38

39 39

39

40

41

41 41

42

REFLECTION................................................................................................ 2.4.8 OPTICAL FIBER TYPES........................................................................................................... .... 2.4.8.1 MULTIMODE FIBER....................................................................................................... ..... 2.4.8.2 SINGLE MODE FIBER............................................... 2.4.8.2 SPECIAL PURPOSE FIBER.. ............................................... 2.4.9 MANUFACTURING PROCESS... ............... 2.4.10 COATINGS ............... 2.4.11 TERMINATION AND SPLICING............... 2.4.12 APPLICATION OF FIBER OPTICS. .......................

43 43 44 45 45 47

48 49

CHAPTER 3

CONCLUSION51 52

3.1 CONCLUSIONS........................................................................................ .................................................................................................................. 3.2 REFERENCES................................................................................................... ..................................... 3.3 BIBLIOGRAPHY............................................................................................... ......................................

52

AN OVERVIEW OF THE COMPANY1.1 Introduction1.1.1 About EOSS:

Emirates Office Systems & Supplies (EOSS), founded in 1989 is 100% UAE nationally owned and headquartered in Abu Dhabi. EOSS has a long history of providing a high standard of professional services and products to the commercial and government sectors, oil and gas industries, academia, hotels and private entities in the United Arab Emirates Because of the company's long presence in the marketplace, EOSS has built an impressive reputation and is considered one of the leading system integrators in the UAE for the following professional services: Technical Textiles Tyre Cord Belting Fabrics Coated Fabrics Industrial Yarn Laminated Fabrics Chemicals Fluorochemicals Fluorospecialities Packaging Films Engineering Plastics

Emirates Office Systems & Supplies offers a wide range of high quality materials and products from leading international manufacturers at competitive rates.

1

EOSS is a customer driven, high performance company, powered by highly trained staff of more than 200 Engineers and Technicians with strong educational and field experience. EOSS is a leading provider of customer-focused information technology outsourcing and communication solutions across the Middle East.

1.1.2 Mission Statement:

EOSS commitment to customers is to: 1. 2. 3. 4. 5. 6. Provide professional services that meet customer needs and exceed customer expectations. Provide quality installations and maintenance that meet the latest standards. Thoroughly test, certify and guarantee all installations. Provide cost effective solutions using the latest technology available. Work with the customers schedule to provide flexible and timely services. Be available to provide short notice services and emergency response.

1.2 Professional Services

2

1.2.1 IT & Telecom Outsourcing & Recruitment:

EOSS can assist in acquiring highly professional trained people in Information Technology. Recruiting can be a time consuming and expensive process - and there are no guarantees that you will hire the right person. EOSS are specialists in sourcing qualified and proven employees. EOSS offers a full range of professional staffing services, from temporary & contract staffing to permanent placements search. By consistently focusing on customers needs and exceeding their expectations EOSS has become one of the most sought out companies in UAE. EOSS can provide: 1. Professional trained people in different IT skills and levels like System Analysts, Programmers, Consultants, Project Coordinator, System Administrator, Database Administrator and Technical Writer. 2. Technically proficient person in IT solutions and applications. 3. Make any recommendation for IT organizational structure.

1.2.2 Structured Cabling:

EOSS provides a comprehensive range of data and telecommunications products and services according to client requirements Multi-Pair Cat 6, Cat 5e Copper Cabling And Accessories. Single And Multimode Fiber Optic Cabling And Accessories. Voice, Data & Video Conferencing. Indoor / Outdoor Installations Including Trenching. Consultancy, Survey, Design, & Project Management Technical Support & Assistance. Cable Trenching, Installation & Supervision. Cable Splicing. Cable Termination, Testing, Labeling & Commissioning. 3

Logistics Support. Fault Finding & Trouble Shooting. Analysis, Modification & Maintenance Services For Existing Annual Maintenance and Support Contracts.

Installations

In addition to experience gained from the successful completion of hundreds of installations, EOSS maintains certifications with a number of manufacturers for structured cabling & telecommunications solutions, including Brand-Rex Levition Lucent Matrix Ozlinx R&M Siemon

Copper and Fiber cabling installations are tested and certified using a variety of standard industry test equipment. EOSS also offers a full line of testing and certification services on existing cable plants. In addition to a wide variety of specialized tools, EOSS also owns leading brands of equipment including, but not limited to: Cable Analyzer Fluke DTX1800 Fluke DSP4000 Fiber or Copper Optical Time Domain Reflectometer (OTDR) Tektronix TFP 2A Fiber Master Single or Multi Mode Corning Communication Media Analyzer CMA 4000 Single Mode Optical Light Source/Power Meter Noyes Fiber System MLP 5-28 Multi Mode Light Pack Ando AC-2161 ARC Fusion Splicer Fujikura FSM 405 4

Splicing Vehicle Nissan Single Cabin with customized air-conditioned enclosure1.2.3 Premises Access Control and Security:

In order to provide a secure environment for clients, EOSS specializes in all aspects of supply, installation and maintenance of: Closed-Circuit TV Surveillance Systems (CCTV) Indoor & Outdoor Alarms Access Systems Standalone Controllers And Readers Short And Long Range Readers RFID Cards (Passive And Active) RFID Elevator Control Car Parking RFID System Locks (Magnetic, Bolt And Electrical)

1.2.4 Wireless Systems:

EOSS can provide solutions which allow a wireless LAN to take full advantage of wired infrastructure resources while also taking care of security, deployment and control issues. Wireless LANs are deployed without cabling for clients in spaces where cables cannot be run, such as hard-to-reach locations within a building, outdoor areas and historical buildings.1.2.5 Office Automation and Electronics:

EOSS provides all types of office automation and electronics maintenance. The EOSS spare parts and maintenance department has highly skilled and dedicated staff that caters to customers electronics maintenance requirements. 5

EOSS can supply and maintain: All types of small and large office electronics including fax machines, telephones and other heavy duty machines. Audiovisual systems and presentation tools including LCD, overhead and slide projectors, etc. Provide general maintenance including civil, electro-mechanical and electrical systems in company-owned accommodations, villas and in privately owned buildings. Repair, overhaul and supply all kinds of electrical, electro-mechanical and non-electrical appliances and accessories. Annual maintenance contracts are also available.

Principle ProductsEOSS offers high quality products including fiber optic cabling, metallic cabling and active and passive accessories from leading international manufacturers at competitive prices.

3M A leading innovator for products and solutions for telecommunications providers specializing in access and enterprise networks and network equipment manufacturing. www.3m.com

Corning To keep pace with the worlds insatiable demand for bandwidth, Cornings ground-breaking telecommunications innovations provide customers with high-quality solutions that bring infinite bandwidth capabilities right to your doorstep. www.corning.com

(Table 1.3.1 Principle Products)

6

1.4 Client Base1.4.1 Government Sector:

Abu Dhabi Crown Prince Court Abu Dhabi Department of Planning & Economy Abu Dhabi Immigration Department Abu Dhabi Future Energy Company MASDAR UAE Federal Immigration UAE Ministry of Finance & Industry UAE Ministry of Information & Culture UAE Ministry of Presidential Affairs UAE Red Crescent Society1.4.2 Oil & Gas Sector:

Abu Dhabi Company for Onshore Oil Operations (ADCO) Abu Dhabi Gas Industries (GASCO) ADMA-OPCO National Drilling Company (NDC) Schlumberger Middle East SA Total Lubricants International Zakum Development Company (ZADCO)1.4.3 IT / System Integrators:

Al Futtaim Telecom Alpha Data Processing Services Bechtel Bin Yaquob Technological Solutions C4 Advanced Solutions (C4) Computer Network Systems (CNS) Emirates Computers Emirates Technology Company (EMITAC) 7

EMIRCOM Group 4 Securities Emirates Gulf Business Machines (GBM) IT-Serve ITQAN Al Bawardi Computer Mid East Data Systems (MDS) Omnix International LLC Sibca Electronics Seven Seas Computers Tele-logic1.4.4 Utilities and Institution: TELECOMMUNICATIONS

DIC Emirates Integrated Telecommunications Company PJSC (du) Etisalat TECOMEDUCATION

Abu Dhabi University Al Khubairat Community School Higher Colleges of Technology Petroleum Institute (PI) Zayed UniversityAVIATION

Abu Dhabi Department of Civil Aviation Abu Dhabi International Airport Etihad Airways Gulf Aircraft Maintenance Company (GAMCO)FINANCIAL SERVICES

Abu Dhabi Investment Company (ADIC) 8

Abu Dhabi National Insurance Company (ADNIC) Invest BankHOSPITALITY AND REAL ESTATE

Abu Dhabi National Hotels Aldar Beach Rotana Hotel & Towers Intercat HospitalityUTILITIES

Abu Dhabi Distribution Company (ADDC)

1.4.5 Electro-Mechanical Contractors:

ABB Industries Abu Hijeh Electrical Contracting Company Al Ain General Contracting Company (ALGECO) Al Hudaiba Contracting LLC Al Mansoori Specialized Engineering LLC Alcatel Trade International Arabian Contracting LLC Axis-Kuwait Hilal BilBadi & Partners Contracting Company TARGET Systems Thermo LLC

9

10

1.5 Major ProjectsEOSS is well-known and respected in the UAE marketplace as both a professional and reputable service provider. EOSS is also considered an unparalleled leader in the field of structured cabling and patch cord provision in the UAE. Following are relevant ongoing and completed projects.

Project Abu Dhabi Exhibition Center Location Abu Dhabi Client Date Computer Network Systems (CNS) Dubai 2008 - Ongoing

Descript Horizontal Cabling System, Fiber ion Network, Data Backbone System and Voice Backbone System. Single Outlet of 5200 points, 51 km of Fiber Optic Cables and 31 km of Multi-pair Cables.

Project Business Bay Location Dubai Client Date Alpha Data 2007

Descript Installation, termination, testing, ion labeling and commissioning of structured cabling network for ten business towers ranging from 28 to 52 floors, totaling 399 floors- including but not limited to CAT6 Cables and components for 23, 727 UTP points.

11

Project Emirates Palace Hotel Location Abu Dhabi Client Date Emirates Computers 2003

Descript Installation, termination, testing, ion labeling and commissioning of Voice backboneincluding but not limited to 270 KM CAT3 Cables and components, and 900 wireless access points.

Project

Dubai International Airport Expansion Phase II Thales International Middle East (SAL) Dubai 2007 - 2008

Location Dubai Client Date

(Table 1.5.1 Major Projects)

12

1.6 CertificationEOSS have been awarded the ISO 9001:2000 (Certificate No. 951074521) quality certification by TV SD America Inc. Management Service Division for passing the Quality Management System in line with Supply, Installation and Professional Services for Communication, Networking, Structure Cabling and Associate Products.

(Figure 1.6: ISO 9001 Certificate)

13

CABLES AND ITS TYPES2.1 Introduction:Definition: 1. A cable is defined by the National Electrical Code (NEC) as: A cable is two or more wires running side by side and bonded, twisted or braided together to form a single assembly. 2. A cable is the term used to describe the complete unit of multiple insulated conductors, strength members, and a cable jacket to keep all the cable elements together. There are three major categories of cables, namely, 1. 2. 3. Co-axial Twisted Pair Fiber Optic

Electrical cables may be made more flexible by stranding the wires. In this process, smaller individual wires are twisted or braided together to produce larger wires that are more flexible than solid wires of similar size. Bunching small wires before concentric stranding adds the most flexibility. Copper wires in a cable may be bare, or they may be plated with a thin layer of another metal, most often tin but sometimes gold, silver or some other material. Tin, gold, and silver are much less prone to oxidation than copper, which may lengthen wire life, and makes soldering easier. Tight lays during stranding makes the cable extensible.

14

Cables can be securely fastened and organized, such as by using cable trees with the aid of cable ties or cable lacing. Continuous-flex or flexible cables used in moving applications within cable carriers can be secured using strain relief devices or cable ties. At high frequencies, current tends to run along the surface of the conductor and avoid the core. This is known as the skin effect. It may change the relative desirability of solid versus stranded wires.

2.2 Coaxial Cables

2.2.1 IntroductionCoaxial cables are made of four layers. At the lowest level you have just an ordinary electrical wire surrounded by insulation. What makes it coaxial is the next layer: A metal layer around the insulation. Taking a round cross-section of the cable, one would find a single center solid wire symmetrically surrounded by a braided or foil conductor. Between the center wire and foil is an insulating dielectric. This dielectric has a large affect on the fundamental characteristics of the cable. A coaxial cable works just like two wires, except one is "inside" the other. Current flows from the power source through one metal layer, the equipment end, and then the power the second flows through at the other flows back to source through metal layer.

15

(Figure 2.2.1 Cross Sectional View)

16

2.2.2 DescriptionCoaxial cable is defined as any cable with the following properties: 1. A center conductor 2. Insulation covering the center conductor, called a "dielectric" 3. A braided shield surrounding the dielectric 4. An optional foil shield 5. An outer jacket 2.2.2.1 Center Conductor: At the heart of a coaxial cable is a center conductor. Typically constructed of pure copper (in higher-end cables) or copper-coated steel or aluminum (in lessexpensive cables), the center conductor is responsible for transmitting the cable's signal. As such, it must meet certain electrical properties (such as wire resistance). The rest of the cable construction is primarily designed to help the center conductor maintain its electrical integrity. 2.2.2.2 Dielectric Insulator: The dielectric insulator's purpose is two-fold; 1. It acts as an insulator between the center conductor and the outer braided / foil shielding. 2. It helps physically hold the center conductor in the center of the cable. Signal loss can occur if the center conductor strays too close to the outer area of the cable. Various materials are commonly used for the dielectric. A few of the more common materials, in order of quality (from best to worst), are below: 3. Foamed Polyethylene (FPE) 4. Teflon 5. Polyethylene (PE) 17

6. Polypropylene (PP) 7. Polyvinylchloride (PVC) Each material has a dielectric constant. The closer this number is to 1.0, the better. Foamed Polyethylene (FPE), for example, generally has a dielectric constant somewhere around 1.5, while PVC's dielectric constant is around 3.0 to 4.0. (Foamed PE basically uses gas, often nitrogen, to create gas bubbles in the material to lower the dielectric constant. Marketing literature that refers to "gasinjected dielectric" usually indicates the use of FPE. It is one of the best dielectric materials in common use.)

(Figure 2.2.2 Coaxial Cable with foil shield)

2.2.2.3 Braided Shield: Long copper cables have a tendency to act like antennas, picking up stray signals from the environment. These unwanted signals, known as "interference", disrupt the signal that the cable is supposed to be carrying. Interference tends to come in 18

two different flavors: electromagnetic interference (known as EMI) and radio frequency interference (RFI). EMI interference is often caused by heavy power lines, cell phone signals, etc. A braided shield protects the signal from EMI interference. When looking at cable specs, the braided shield will often be expressed in a percent coverage, which often ranges anywhere from 30% to 95% coverage. The higher the coverage, the better the protection.

2.2.2.4 Foil Shield: Although not always present on coaxial cables, the foil shield serves to protect from RFI interference. Foil shields are almost always made out of aluminum foil, and simply wrap around the inner parts of the cable. Unlike braided shields, which have a percent coverage, foil shields always cover 100%. 2.2.2.5 Outer Jacket The outer jacket is generally made out of flexible PVC (polyvinyl chloride) and serves primarily to hold the cable together and protect it from the elements.

2.2.3 CharacteristicsCoaxial cables, commonly called coax cables, are used to transmit analog video signals. These cables are constructed in a special way to provide optimal signal transfer while insuring adequate shielding from outside interference. The center conductor (dielectric) of a coax cable carries the video signal and the outside conductor (shield) is used as a return wire and shield. Coax cable specifications rate characteristics such as 1. Impedance 19

2. Attenuation 3. Velocity of propagation 4. Shielding percentage 5. American Wire Gauge 2.2.3.1 Impedance: A coax cable's impedance must match the impedance of the source and destination equipment, which for most video systems is 75 Ohms. 2.2.3.2 Attenuation: is specified as the amount of signal decrease per 100 feet of cable at certain frequencies and is measured in decibels (dB). This specification correlates to the bandwidth of the cable. 2.2.3.3 Velocity of propagation: is determined by the insulator type used between the center conductor and the shield and is measure as a percent. This number shows the speed of the signal in the coax cable as compared to the speed of light in a vacuum. 2.2.3.4 Shielding percentage: shows the effectiveness of the outside shield and / or foil braid. The higher the percentage, the better the cable resists interference. 2.2.3.5 American Wire Gauge: The center conductor thickness is called gauge and is specified as AWG (American Wire Gauge). The smaller the AWG number of a coax cable the better it is at transmitting high bandwidth signals. A smaller AWG means a thicker diameter wire, and in general a thicker wire gives better performance.

2.2.4 ConnectorsThere are many different connectors that can terminate a coaxial cable. A few of the common types include 2.2.4.1 RCA

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The RCA connector was developed in the early '40s by the Radio Corporation of America to connect record players to amplifiers. The same basic connector is still in wide use today, and it represents a large portion of the connectors used for home theater cables. The fact that they are so easy to connect and disconnect makes RCA connectors a popular choice for home theater applications. RCA cables can be used for audio, video and digital audio.

(Figure 2.2.4.1 RCA Connector) The biggest drawback with RCA devices is that each signal is sent on a different cable. For example, a single RCA-terminated coax cable only carries the left audio channel, or only the right, etc. Three RCA cables are needed for high-def video, along with two more for the audio. This makes for a mess of cables behind your equipment. Attaching RCA connectors can be a bit more time-consuming as, with some types of RCA connectors, the coaxial cables wires need to be soldered to the connector after stripping the cable with a stripping tool. RCA connectors come in solder-on, weatherproof and compression styles. A special tool is required for compression connectors, and a soldering iron is needed for solder-on connectors. 2.2.4.2 BNC

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The BNC (Bayonet Neill-Concelman) connector is a very common type of RF connector used for terminating coaxial cable. The BNC connector has two bumps on the female side that slide into corresponding grooves on the male side. The connector is then rotated a quarter turn to lock into place. BNC connectors are widely used in commercial applications such as closed circuit television systems, where its ability to lock in place (unlike the slip-on RCA) makes BNC cables a perfect fit. BNC connectors come in a wide variety as well, including twist-on and weatherproof connectors.

(Figure 2.2.4.2 BNC Connector)

2.2.4.3 F-Pin The F-pin connector is probably the most recognized of the coaxial connectors as it's been in use with televisions and VCRs for decades. The familiar threaded connector makes for a secure connection that will not easily slip out of a device. This connector is also one of the easiest to attach to a coax cable as it does not require any soldering. Many different types are available including twist-on, 22

crimp-on and compression. For outdoor use, weatherproof connectors are also available to create an F-Pin cable with a secure connection and loss-less signal transfer.

(Figure 2.2.4.3 F-Pin Connector)

2.2.5 Types of Coaxial Cables2.2.5.1 RG58 Core diameter: 0.9mm Impedance: 75 Largely used in the commercial security camera industry, RG58 cable is a low profile, inexpensive choice for large projects where a high-bandwidth cable is not needed. Most often terminated with BNC connectors, this type of cable can also be found attached to testing equipment and 2-way radio systems. 2.2.5.2 RG59 Core diameter: 0.81mm Impedance: 50 Once the standard for cable TV, RG59 cables are still found packaged with VCRs and televisions. RG59 was a good low-cost option for cable TV for years until the cable industry recently began its move into digital cable television, which needs a 23

thicker cable. Modern satellite television also requires a higher-bandwidthcapable cable and so RG6 coaxial cable is becoming much more popular, making RG59 no longer the industry standard. 2.2.5.3 RG6 Core diameter: 1.0mm Impedance: 75 RG6 cable is differentiated from RG59 cable by having a thicker copper center conductor. The most commonly-recognized variety of RG-6 is cable television (CATV) distribution coax, used to route cable television signals to and within homes, and RG-6 type cables have become the standard for CATV, mostly replacing the smaller RG-59, in recent years. CATV distribution coax typically has a copper-coated steel center conductor and a combination aluminum foil/aluminum braid shield, typically with low coverage (about 60%). RG-6 type cables are also used in professional video applications, carrying either baseband analog video signals or serial digital interface (SDI) signals; in these applications, the center conductor is ordinarily solid copper, the shielding is much heavier (typically aluminum foil/ 95% copper braid), and tolerances are more tightly controlled, to improve impedance stability.

RG-6 cables typically are fitted with various types of connector at each end; in CATV distribution applications, these are typically F connector style; in professional baseband video, BNC connectors; and in consumer a/v applications other than RF and CATV, RCA plugs.

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RG58

RG59(Figure 2.2.5 - Different Cable Types)

RG6

2.2.6 Advantages / Disadvantages2.2.6.1 Advantages The purpose of coaxial cables is to eliminate magnetic effects. In a coaxial cable, the current of the inside and outside layers flow in opposite directions. Their magnetic fields are in opposite directions. The magnetic field from the outside wire cancels the magnetic field from the inside wire. Although there is magnetic field between the metal layers, there is no field outside the cable. Also, a coaxial cable is not affected by magnetic fields from other wires. The primary advantage of coaxial cable compared to twisted pair is the braided metal shield is very good at blocking electromagnetic signals from entering the cable and producing noise. And has also been used for long-distance telephone transmission, as the cabling within a local area network, and as a connector between a computer terminal and a mainframe computer.

2.2.6.2 Disadvantages

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1. Signals entering the cable can cause unwanted noise and picture ghosting. Excessive noise can overwhelm the signal, making it useless. 2. A continuous current flow, even if small, along the imperfect shield of a coaxial cable can cause visible or audible interference. 3. More expensive than twisted pairs and is not supported for some network standards. 4. Its also very bulky and also has high attenuation so would have the need to implement repeaters

2.2.7 Fiber, Coax or UTP?2.2.7.1 Cost Consideration UTP lets the end user share cable to reduce both labor and cable costs. Multiple pairs in a single cable can be used for video signals with control or video signals with 24VAC power. The end user can even share video with ringing telephones or data lines all noise-free. With UTP, systems also can be designed to maximize cable usage. End users with a plenum environment also can benefit from UTP, as the cable is jacketed with two types of material: PVC, a low-grade plastic, and plenum, which is fire-rated Teflon. PVC coax costs up to 50 percent less than plenum coax, which is required by most fire codes for ceiling and in-wall wiring in commercial buildings. As the number of coax cables needed increases, each extra coax adds its own plenum jacket, while UTP can have up to 100 UTP pairs under one plenum jacket. The amount saved on the wire and the labor to pull it really adds up as the number of required pairs increase. UTP transmission is significantly less costly than fiber, from cable and installation costs to tooling and transceivers. The most important comparison, however, is that of quality. Passive to active UTP systems offer performance similar to fiber, providing noise immunity, attenuation compensation, surge protection and 26

ground loop isolation. Because of this, some who once used fiber for runs beyond the range of coax now choose UTP for transmission.

2.2.7.2 Size UTP wire is at least one-tenth the size of RG-59, costs about one-eighth for nonplenum and as little as one-thirtieth for plenum cable. The physical size of the cable makes it easier to pull. Termination is much simpler than coax because no crimping is involved. Wire pairs are easily identified by their different colors. Surge protection, ground loop isolation, distance equalization and interference immunity are each superior to that of coax. 2.2.7.3 Distance If cable runs less than 250 feet, coax is probably the best option. Between 250 and 8,000 feet, UTP wire is often the best choice. And if more than 8,000 feet fiber optic cable is the best option. At short distances, however, the cost of the UTP transceivers becomes a factor. Typically, coax costs less for small camera counts on non-plenum wire that is less than 250 feet in length. In most other cases, UTP is more economical.

2.2.8 Uses

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(Figure 2.2.8 Coaxial Cable)

1. Coaxial cables are used to transmit analog video signals. These cables are constructed in a special way to provide optimal signal transfer while insuring adequate shielding from outside interference. 2. Short coaxial cables are commonly used to connect home video equipment, in ham radio setups, and in measurement electronics. They used to be common for implementing computer networks; in particular Ethernet but twisted pair cables have replaced them in most applications except in the growing consumer cable modem market for broadband internet access. 3. Long distance coaxial cable is used to connect radio networks and television networks, though this has largely been super ceded by other more high tech methods like fiber optic systems. It still carries cable television signals to majority television receivers, and this purpose consumes the majority of coaxial cable production 4. Micro Coaxial cables are used in range of consumer devices, military equipment, and also in ultra-sound scanning equipment. 5. The most common impedances that are widely used are 50/ 52 and 75, although other impedances are available for specific applications. The 50/52cables are widely used for industrial and commercial radio frequency application (including radio and telecommunications). 75 is commonly used for domestic television and radio.

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2.3

Twisted Pair Cable

2.3.1 General Overview:Twisted pair cable consists of a pair of insulated wires twisted together. It is a cable type used in telecommunication for very long time. Cable twisting helps to reduce noise pickup from outside sources and crosstalk on multi-pair cables. Twisted pair cable is good for transferring balanced differential signals. The practice of transmitting signals differentially dates back to the early days of telegraph and radio. The advantages of improved signal-to-noise ratio, crosstalk, and ground bounce that balanced signal transmission brings are particularly valuable in wide bandwidth and high fidelity systems. By transmitting signals along with a 180 degree out-of-phase complement, emissions and ground currents are 29

theoretically canceled. This eases the requirements on the ground and shield compared to single ended transmission and results in improved EMI performance. (Figure 2.3.1.1 25-pair color code Chart) Noise sources introduce signals into the wires by coupling of electric or magnetic fields and tend to couple to both wires equally. The noise thus produces a common-mode signal which is cancelled at the receiver when the difference signal is taken. This method starts to fail when the noise source is close to the signal wires; the closer wire will couple with the noise more strongly and the common-mode rejection of the receiver will fail to eliminate it. This problem is especially apparent in telecommunication cables where pairs in the same cable lie next to each other for many miles. One pair can induce crosstalk in another and it is additive along the length of the cable. Twisting the pairs counters this effect as on each half twist the wire nearest to the noise-source is exchanged. Providing the interfering source remains uniform, or nearly so, over the distance of a single twist, the induced noise will remain common-mode. Differential signaling also reduces electromagnetic radiation from the cable, along with the associated attenuation allowing for greater distance between exchanges. The twist rate (also called pitch of the twist, usually defined in twists per meter) makes up part of the specification for a given type of cable. Where nearby pairs have equal twist rates, the same conductors of the different pairs may repeatedly lie next to each other, partially undoing the benefits of differential mode. For this reason it is commonly specified that, at least for cables containing small numbers of pairs, the twist rates must differ.

The common types of twisted pair cables are: 1. 2. 3. 4. Unshielded Twisted Pair (UTP) Shielded Twisted Pair (STP) Foiled Twisted Pair (FTP) Screened shielded/foiled twisted pair (S/STP or S/FTP)

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In contrast to FTP (foiled twisted pair) and STP (shielded twisted pair) cabling, UTP (unshielded twisted pair) cable is not surrounded by any shielding. It is the primary wire type for telephone usage and is very common for computer networking, especially as patch cables or temporary network connections due to the high flexibility of the cables. Here are some common cable types you might encounter in telecommunication installations: 1. 100 ohm unshielded twisted pair: modern structured cabling systems (CAT 3, CAT 4, CAT 5, CAT 6) used to carry telephone signal and networking signals within buildings 2. 3. 120 ohm unshielded twisted pair: Some older telecommunication cables on the field 150 ohm shielded twisted pair: Those are generally used for some older networking systems like IBM cabling system used for Token Ring network. 150 ohm shielded twisted pair cable is also sometimes used to carry balanced audio signals and automation systems signals. 4. 5. 75 ohm coaxial cable: video interconnection, CCTV, common antenna wiring, cable TV, some telecommunication signals 50 ohm coaxial cable: antenna wiring for radio transmitters, WLAN cards, cellular phone base stations etc.

(Figure 2.3.1.2 Twisted Cable)

2.3.2 Unshielded Twisted Pair:

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Unshielded Twisted Pair cables were first used in telephone systems by Alexander Graham Bell in 1881. Today, most of the millions of kilometers of twisted pairs in the world are outdoor landlines, owned by telephone companies, used for voice service, and only handled or even seen by telephone workers.

(Figure 2.3.2.1 Unshielded Twisted Pair) UTP cables are found in many Ethernet networks and telephone systems. For indoor telephone applications, UTP is often grouped into sets of 25 pairs according to a standard 25-pair color code originally developed by AT&T. A typical subset of these colors (white/blue, blue/white, white/orange, orange/white) shows up in most UTP cables. For urban outdoor telephone cables containing hundreds or thousands of pairs, the cable is divided into smaller but identical bundles. Each bundle consists of twisted pairs that have different twist rates. The bundles are in turn twisted together to make up the cable. Pairs having the same twist rate within the cable can still experience some degree of crosstalk. Wire pairs are selected carefully to minimize crosstalk within a large cable.

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Typical UTP cable has four pairs of wires in each cable. Not all four pairs are used in actual applications. For most LANs, only two pairs are used, one in each direction to allow full duplex, simultaneous bidirectional communications. Due to the limitation on bandwidth and emission of radiation that could potentially affect other electronic devices, the higher speed networks are migrating toward using all four pairs. (Figure 2.3.2.2 UTP) The quality of UTP may vary from telephone-grade wire to extremely high-speed cable. The cable has four pairs of wires inside the jacket. Each pair is twisted with a different number of twists per inch to help eliminate interference from adjacent pairs and other electrical devices. The tighter the twisting, the higher the supported transmission rate and the greater the cost per foot. The EIA/TIA (Electronic Industry Association/Telecommunication Industry Association) has established standards of UTP and rated six categories of wire (additional categories are emerging).

2.3.2.1 UTP Applications:UTP cable is also the most common cable used in computer networking. Modern Ethernet, the most common data networking standard, utilizes UTP cables. Twisted pair cabling is often used in data networks for short and medium length connections because of its relatively lower costs compared to optical fiber and coaxial cable. UTP is also finding increasing use in video applications, primarily in security cameras. Many middle to high-end cameras include a UTP output with setscrew 33

terminals. This is made possible by the fact that UTP cable bandwidth has improved to match the baseband of television signals. While the video recorder most likely still has unbalanced BNC connectors for standard coaxial cable, a balun is used to convert from 100-ohm balanced UTP to 75-ohm unbalanced. A balun can also be used at the camera end for ones without a UTP output. Only one pair is necessary for each video signal.

2.3.2.2 Cable Categories:Categories of Unshielded Twisted Pair Categor y 1 2 3 4 5 1000 Mbps (4 pair) 5e 6 1,000 Mbps 10,000 Mbps Gigabit Ethernet Gigabit Ethernet Gigabit Ethernet 1 Mbps 4 Mbps 16 Mbps 20 Mbps 100 Mbps (2 pair)Speed

Use Voice Only (Telephone Wire) Local talk & Telephone (Rarely used) 10BaseT Ethernet Token Ring (Rarely used) 100BaseT Ethernet

(Table 2.3.3.1 Table for Data speeds)

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The "quality" of the cabling systems to carry high frequency signals is expressed with the following marking: 1. Cat 1: Cabling that meets the minimum requirements for analog voice or Plain Old Telephone Service (POTS). Also known with name Grade 1. Commonly called inside wire by the Telco community. 2. Cat 2: This is a 100 ohm UTP system capable of operating 1 Mbps Token Ring and similar networks. This is also known as IBM Type 3 cabling system. Also known with name Grade 2. 3. Cat 3: This cable type is characterized to 16 MHz and supports applications up to 10 Mbps. Applications may range from voice to 10BASE-T. This is a low performance cable rating which is disappearing. This is nowadays the minimal requirement for good quality structured telephone cabling system. This is also known as ISO/IEC 11801 Class C cabling. This was the standard for UTP performance as late as 1988. The FCC recently changed the requirement for telephone inside wiring to minimum of Cat 3 due to crosstalk problems with non twisted quad-four. CAT 3 is no longer recognized by TIA. 4. Cat 4: This cable type is characterized to 20 MHz and supports applications up to 16 Mbps. Applications may range from voice to 10BASE-T and 16 Mbps Token Ring. This cable type is not much used nowadays. 5. Cat 5: The traditional rating of cables for high speed data installation. Rated frequency is 100 MHz. This cable works well from voice to 100BASE-T Ethernet and 155Mbps ATM. This cable type is also known as ISO/IEC 11801 Class D cabling. Today Cat 5 copper communications wiring is the recognized minimum for broadband services. The standard for this wiring are ISO/IEC-11801 and TIA/EIA-568-A-5. CAT5 performance is only possible when cable, connector modules, patch cords, and all electronics carry the same CAT5 rating. 6. Cat 5e: New rating developed in USA. Rated frequency is 100 MHz. Cat 5E is becoming the new standard for premises wiring, because it is recommended

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as the minimum for all future installations by TIA/EIA, IEEE and many equipment manufacturers. Enhanced Category 5 was ratified in 1999. 7. Cat 6: A new rating just developed in US, ISO/IEC and CENELEC. Rated frequency is 200 MHz with some requirements specified for 250 MHz. Category 6 is being specified concurrently by both ISO in the 11801-2001 document and the TIA in its Category 6 addendum to TIA 568B (ANSI/TIA/EIA568-B.2-1 ratified by the TIA/EIA in June 2002). This presents the best performance possible with the current T568A and T568B wiring configurations on an 8 position 8 conductor modular connector (RJ-45). In Europe this is known as ISO/IEC 11801 Class E cabling. 8. Cat 7: A rating for individual pair screened cables derived from the German DIN 44312-2 standard requirements. Rated frequency is 600 MHz. The work is on progress. This is also known as ISO/IEC 11801 Class E. This cable is fully shielded and uses non-standard RJ-45 interface (Alcatel hybrid RJ-45 connector).This cabling is primarily for European market place. Other alternative connector style is IBM Mini-C connector. In Europe this is known as Class F cabling.

2.3.2.3 Commonly Used UTP Cables:The three most popular and widely used cables are Cat 5, Cat 5e, and Cat 6. It is important to pick the right category cable for the project that you are doing. The reason why it is important is because you will know that you will be able to obtain a certain level of performance from your network by having installed the correct category cable. Cat 5 Category 5 cable can be used to carry Ethernet traffic of up to 100Mbit/s and ATM of up to 155Mbit/s. The standard cable of an Ethernet 100Base-TX is Cat 5. Cat 5 is a twisted pair cable created for high signal integrity. Some are unshielded while others are shielded. Cat 5 is used in structured cabling for computer networks, token ring, basic voice services, and ATM. The Category 5 cable has four twisted 36

pairs in a single cable jacket. Cat 5 generally has three twists per inch of each individual twisted pair of 24 gauge wires inside of the cable. Cat 5e Category 5e is an upgraded version of the Cat 5 standard and is capable of carrying data up to 1000Mbit/s. Cat 5e is the standard cable for use in Ethernet 1000Base-T. Cat 5e is able to carry data longer distances than Cat 5. Cat 5e can be used confidently for 350 meters. Cat 5e has better performance measures. It also has more complex internals. Cat 5e exists in both solid conductor forms and stranded forms. Stranded is much more flexible and is used for military applications. Cat 5e is terminated in two different schemes, but there is no difference in the scheme used. Cat 6 Cat 6 is similar to Cat 5e but is designed with even stricter standards. Cat 6 is backward compatible with Cat 5/Cat 5e. Cat 6 has a standard performance of 250 MHz and works with 1000BASE-T and 10BASE-T / 100BASE-TX. It also works with 10GBASE-T standard, but there are limits if Cat 6 unshielded cable is used. Like earlier Cat 5e/ Cat 5, Cat 6 contains four twisted copper wire pairs. The cable is made usually with 22 to 24 AWG gauge wire. Cat 6, when used in a patch cable function, is often terminated with a RJ-45 connection. One may use Cat 5, Cat 5e, or Cat 6 in the same project, but the signal will be limited to the lowest category copper cable. When deciding on which category cable to use, make sure to pick a cable that not only meets your current needs but your future needs as well.

2.3.3 Shielded Twisted Pair:Although UTP cable is the least expensive cable, it may be susceptible to radio and electrical frequency interference (it should not be too close to electric motors, fluorescent lights, etc.). If you must place cable in environments with lots 37

of potential interference, or if you must place cable in extremely sensitive environments that may be susceptible to the electrical current in the UTP, shielded twisted pair may be the solution. Shielded cables can also help to extend the maximum distance of the cables. Twisted pair cables are often shielded in attempt to prevent electromagnetic interference. Because the shielding is made of metal, it may also serve as a ground. However, usually a shielded or a screened twisted pair cable has a special grounding wire added called a drain wire. This shielding can be applied to individual pairs, or to the collection of pairs. When shielding is applied to the collection of pairs, this is referred to as screening. The shielding must be grounded for the shielding to work. STP cabling includes metal shielding over each individual pair of copper wires. This type of shielding protects cable from external EMI (electromagnetic interferences). e.g. the 150 ohm shielded twisted pair cables defined by the IBM Cabling System specifications and used with token ring networks.

(Figure 2.3.3.1 STP)

2.3.4 Termination38

The termination of TP cables are mostly carried out by Crimping. There are three standards which are followed when crimping. TIA/EIA-568-B is a set of three telecommunications standards from the Telecommunications Industry Association, a 1988 offshoot of the Electronics Industry Association. The standards address commercial building cabling for telecom products and services. The three standards are formally titled ANSI/TIA/EIA-568-B.1Left to right, RJ connectors:

2001, -B.2-2001, and -B.3-2001. Perhaps the widest known feature of TIA/EIA-568-B.1-2001 is the definition of pin/pair assignments for eightconductor 100-ohm balanced twisted-pair cabling, such as Category 3, Category 5 and Category 6 unshielded twisted-pair (UTP) cables. These assignments are named T568A and T568B and they define the pin out, or order of connections, for wires in 8P8C eightpin modular connector plugs and sockets. Although these definitions

an eight-contact 8P8C plug (used for RJ49,

RJ61 and others, but often called "RJ45" because of its outward semblance to the true RJ45). six-contact RJ25 plug. four-contact RJ14 plug (often also used

instead of two-pin RJ11). a four-contact handset plug (also

popularly, though incorrectly, called "RJ22", "RJ10", or "RJ9"). RJ25 and RJ14 can be plugged into the same standard six-pin jack, pictured.

(Figure 2.3.4.1 RJ connections)

consume only one of the 468 pages in the standards documents, a disproportionate amount of attention is paid to them. This is because cables that are terminated with differing standards on each end will not function normally. LAN Wiring is defined by EIA/TIA. The most important wiring standard in this is EIA/TIA 568 wiring standard. EIA/TIA 568A and 568B are two wiring methods used to indicate which colors are assigned to which pin of the modular jack 39

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(Figure 2.3.4.2 Terminated Cable) Almost all Rj-45 connectors come with wiring markings on them having two wire color possibilities printed to the connector, usually referred as "A" and "B". What is meant by the "A" and "B" markings? The "A" Wiring Scheme is the new wiring for telephone companies and are found in all new residential and commercial wiring applications. The "B" Wiring Scheme was used by AT&T for commercial wiring applications when they had monopoly over wiring new buildings. Those both wiring color schemes are listed in the EIA/TIA 568 wiring standard. Hence, while wiring it does not matter which one of those are used, as long as the whole wiring is done in the same way. There is no performance difference, just different wire colors used for different pins, but the wiring from connector to connector is electrically same.Pi T568A n Pair 1 3 2 3 3 2 4 1 5 1 6 2 7 4 T568B Wir T568A Color T568B Color Pair e 2 2 3 1 1 3 4 tip white/green stripe rin g green solid white/orange stripe orange solid Pins on plug face (socket is reversed)

tip white/orange white/green stripe stripe rin g blue solid blue solid tip white/blue stripe rin g orange solid tip white/blue stripe green solid

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white/brown stripe 8 4 4 rin g brown solid

white/brown stripe brown solid

(Table 2.3.4.1 Color Code)

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2.3.5 Advantages / Disadvantages2.3.5.1 Advantages of Twisted Pair:1. 2. 3. 4. It is a thin, flexible cable that is easy to string between walls. More lines can be run through the same wiring ducts. UTP costs less per meter/foot than any other type of LAN cable. STP significantly reduces external interference.

2.3.5.2 Disadvantages of Twisted Pair:1. 2. 3. 4. STP is bulky and difficult to work with. Narrower bandwidth of operation than Co-axial cables Skin effects can cause signal attenuation Twisted pairs susceptibility to electromagnetic interference greatly depends on the pair twisting schemes (usually patented by the manufacturers) staying intact during the installation. As a result, twisted pair cables usually have stringent requirements for maximum pulling tension as well as minimum bend radius. This relative fragility of twisted pair cables makes the installation practices an important part of ensuring the cables performance. 5. In video applications that send information across multiple parallel signal wires, twisted pair cabling can introduce signaling delays known as skew which results in subtle color defects and ghosting due to the image components not aligning correctly when recombined in the display device. The skew occurs because twisted pairs within the same cable often use a 43

different number of twists per meter so as to prevent common-mode crosstalk between pairs with identical numbers of twists.

2.3.6

Same Concerns

2.3.6.1 Electronic Noise: Electronic noise is a random fluctuation in an electrical signal, a characteristic of all electronic circuits. Noise generated by electronic devices varies greatly, as it can be produced by several different effects. Thermal noise and shot noise are inherent to all devices, while other types depend mostly on manufacturing quality and semiconductor defects. While noise is generally unwanted, it can serve a useful purpose in some applications, such as random number generation or dithering. 2.3.6.2 Thermal noise: JohnsonNyquist noise is generated by the random thermal motion of charge carriers (usually electrons), inside an electrical conductor, which happen regardless of any applied voltage. Thermal noise is approximately white, meaning that its power spectral density is nearly equal throughout the frequency spectrum. A communication system affected by thermal noise is often modeled as an additive white Gaussian noise (AWGN) channel. As the amount of thermal noise generated depends upon the temperature of the circuit, very sensitive circuits such as preamplifiers in radio telescopes are sometimes cooled in liquid nitrogen to reduce the noise level. 2.3.6.3 Shot Noise:

44

Shot noise in electronic devices consists of random fluctuations of the electric current in an electrical conductor, which is caused by the fact that the current is carried by discrete charges (electrons). 2.3.6.4 Flicker Noise: Flicker noise, also known as 1/f noise, is a signal or process with a frequency spectrum that falls off steadily into the higher frequencies, with a pink spectrum. It occurs in almost all electronic devices, and results from a variety of effects, though always related to a direct current. 2.3.6.5 Burst Noise: Burst noise consists of sudden step-like transitions between two or more levels (non-Gaussian), as high as several hundred milli-volts, at random and unpredictable times. Each shift in offset voltage or current lasts for several milliseconds, and the intervals between pulses tend to be in the audio range (less than 100 Hz), leading to the term popcorn noise for the popping or crackling sounds it produces in audio circuits. 2.3.6.6 Avalanche Noise: A junction phenomenon in a semiconductor, which carriers in a high-voltage gradient develops sufficient energy to dislodge additional carriers through physical impact. This agitation creates ragged current flows which are indicated by noise. The noise produced when a junction diode is operated at the onset of avalanche breakdown. 2.3.6.6 Cross-Talk: In electronics, crosstalk (XT) is any phenomenon by which a signal transmitted on one circuit or channel of a transmission system creates an undesired effect in another circuit or channel. Crosstalk is usually caused by undesired capacitive, 45

inductive, or conductive coupling from one circuit, part of a circuit, or channel, to another. In telecommunication, crosstalk is often distinguishable as pieces of speech or signaling tones leaking from other people's connections. If the connection is analog, twisted pair cabling can often be used to reduce the effects of crosstalk. Alternatively, the signals can be converted to digital form, which is much less susceptible to crosstalk. In wireless communication, crosstalk is often denoted co-channel interference, and is related to adjacent-channel interference. In Cabling, crosstalk can refer to electromagnetic interference from an unshielded twisted pair to another twisted pair, normally running in parallel. 1. 2. Near End Crosstalk (NEXT) is interference between two pairs of a cable measured at the same end of the cable as the transmitter. Far end crosstalk (FEXT) is interference between two pairs of a cable measured at the other end of the cable from the transmitter.

2.3.6.6 Electromagnetic Interference: Electromagnetic interference (or EMI) is a disturbance that affects an electrical circuit due to either electromagnetic conduction or electromagnetic radiation emitted from an external source. The disturbance may interrupt, obstruct, or otherwise degrade or limit the effective performance of the circuit. The source may be any object, artificial or natural, that carries rapidly changing electrical currents, such as an electrical circuit, the Sun or the Northern Lights. EMI can be intentionally used for radio jamming, as in some forms of electronic warfare, or can occur unintentionally, as a result of spurious emissions for example through inter-modulation products, and the like. It frequently affects the

46

reception of AM radio in urban areas. It can also affect cell phone, FM radio and television reception, although to a lesser extent. Radiated EMI or RFI may be broadly categorized into two types; 1. 2. Narrowband Broadband.

Narrowband interference usually arises from intentional transmissions such as radio and TV stations, pager transmitters, cell phones, etc. Broadband interference usually comes from incidental radio frequency emitters. These include electric power transmission lines, electric motors, etc. Anywhere electrical power is being turned off and on rapidly is a potential source. The spectra of these sources are generally stronger at low frequencies and diminishing at higher frequencies, though this noise is often modulated, or varied, by the creating device in some way. Included in this category are computers and other digital equipment as well as televisions.

2.3.6.9 Fire Hazards:The electrical cable jacket material is a potential source of fuel for fires. Combustible cable jackets may catch on fire and cable fires can thus spread along a cable tray within a structure. This is easily prevented through the use of fire-retardant cable jackets or in tumescent or endothermic fireproofing or fire retardants. To limit the spread of fire along cable jacketing, one may use cable coating materials or one may use cables with jacketing that is inherently fire retardant. The plastic covering on some metal clad cables may be stripped off at installation to reduce the fuel source for accidental fires. In Europe in particular, it is often customary to place inorganic wraps and boxes around cables in order to safeguard the adjacent areas from the potential fire threat associated with unprotected cable jacketing. To provide fire protection to a cable, there are two methods: 47

1. 2.

Insulation material is deliberately added up with fire retardant materials The copper conductor itself is covered with mineral insulation (MICC cables).

Additionally, extra care should be taken in the type of insulation and cable jacket used, as the material can degrade under extreme condition and become a major health and safety hazard. For example, in a fire, PVC-coated wires can form HCl fumes. Even though the chlorine released reacts with the free-radicals and thus is the source of the material's fire retardance, HCl fumes possess a serious health hazard. This HCL fumes also dissolves in moisture particularly in areas where the air is cool enough to breathe, making it unavailable for inhalation. So, in tunnels and communal areas (where smoke is a major hazard) PVC-free cable insulation is preferred, such as low smoke zero halogen (LSZH or LS0H). 2.3.6.9.1 Passive Fire Protection: Passive fire protection (PFP) is an integral component of the three components of structural fire protection and fire safety in a building. PFP attempts to contain fires or slow the spread, using various structures and techniques as mentioned below: 1. Fire-resistance rated walls They are also designed to sub-divide buildings such that if collapse occurs on one side, it would not affect the other. They can also be used to eliminate the need for sprinklers. 2. Fire-resistance glass The glass has multi-layer in tumescent interlayer technology which meets ASTM-E119 test standards, and is optically clear. It can be used in 60 minute and 120 minute fire resistance rated assemblies. 3. Occupancy separations They are barriers which are intended to divide sectors of buildings; for example, apartments on one side and shops on the other side of the occupancy separation. 4. Cable coating

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The application of fire-retardants, either endothermic or in tumescent, to reduce flame spread and smoke development of combustible cablejacketing 5. Fireproofing cladding Boards used for cladding the cables and in the same applications as spray fireproofing. Materials for such cladding include perlite, vermiculite, calcium silicate, gypsum, DuraSteel, MicroTherm.

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2.4 Fiber Optic Cables2.4.1 Description

An optical fiber cable is a cable containing one or more optical fibers. The optical fiber elements are typically individually coated with plastic layers and contained in a protective tube suitable for the environment where the cable will be deployed.

(Figure 2.4.1 Light in Fiber Optic Cable)

2.4.2 HistoryThe groundbreaking event happened in around 1965, Charles K. Kao and George A. Hockham of the British company Standard Telephones and Cables (STC) were the first to promote the idea that the attenuation in optical fibers could be 50

reduced below 20 decibels per kilometer (dB/km), allowing fibers to be a practical medium for communication.[8] They proposed that the attenuation in fibers available at the time was caused by impurities, which could be removed, rather than fundamental physical effects such as scattering. They correctly and systematically theorized the light-loss properties for optical fiber, and pointed out the right material to manufacture such fibers silica glass with high purity. This discovery led to Kao being awarded the Nobel Prize in Physics in 2009. NASA used fiber optics in the television cameras that were sent to the moon. At the time its use in the cameras was 'classified confidential' and only those with the right security clearance or those accompanied by someone with the right security clearance were permitted to handle the cameras.

2.4.3

Cable types

1. OFC: Optical fiber, conductive 2. OFN: Optical fiber, nonconductive 3. OFCG: Optical fiber, conductive, general use 4. OFNG: Optical fiber, nonconductive, general use 5. OFCP: Optical fiber, conductive, plenum 6. OFNP: Optical fiber, nonconductive, plenum 7. OFCR: Optical fiber, conductive, riser 8. OFNR: Optical fiber, nonconductive, riser 9. OPGW: Optical fiber composite overhead ground wire

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(Figure 2.4.3.1 - Cross-section view of Fiber cables)

2.4.4 Jacket materialThe jacket material is application specific. The material determines the mechanical robustness, aging due to UV radiation, oil resistance, etc. Nowadays PVC is being replaced by halogen free alternatives, mainly driven by more stringent regulations. UV Resistanc e Good Good Poor ? Fair? Remark Good for indoor use Being replaced by LSFH Polymer Good for outdoor applications Highly flexible cables Good for indoor use

Material LSFH Polymer

Halogenfree Yes

Polyvinyl chloride (PVC) No Polyethylene (PE) Polyurethane (PUR) Polybutylene terephthalate (PBT) Polyamide (PA) Yes Yes Yes Yes

Good-Poor Indoor and outdoor use 52

(Figure 2.4.4.1 Table Types of jacket material)

2.4.5 Working of Fiber OpticAn optical fiber is a cylindrical dielectric waveguide (nonconducting waveguide) that transmits light along its axis, by the process of total internal reflection. The fiber consists of a core surrounded by a cladding layer, both of which are made of dielectric materials. To confine the optical signal in the core, the refractive index of the core must be greater than that of the cladding. The boundary between the core and cladding may either be abrupt, in step-index fiber, or gradual, in gradedindex fiber.

2.4.6 Refraction IndexThe index of refraction is a way of measuring the speed of light in a material. Light travels fastest in a vacuum, such as outer space. The actual speed of light in a vacuum is about 300,000 kilometers (186 thousand miles) per second. Index of refraction is calculated by dividing the speed of light in a vacuum by the speed of light in some other medium. The index of refraction of a vacuum is therefore 1, by definition. The typical value for the cladding of an optical fiber is 1.46. The core value is typically 1.48. The larger the index of refraction, the slower light travels in that medium. From this information, a good rule of thumb is that signal using optical fiber for communication will travel at around 200 million meters per second. Or to put it another way, to travel 1000 kilometers in fiber, the signal will take 5 milliseconds to propagate. Thus a phone call carried by fiber between Sydney and New York, a 12000 kilometer distance, means that there is an absolute minimum delay of 60 milliseconds (or around 1/16th of a second) between when one caller speaks to when the other hears. (Of course the fiber in this case will probably travel a longer route, and there will be additional delays

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due to communication equipment switching and the process of encoding and decoding the voice onto the fiber).

2.4.7

Total internal reflection

When light traveling in a dense medium hits a boundary at a steep angle (larger than the "critical angle" for the boundary), the light will be completely reflected. This effect is used in optical fibers to confine light in the core. Light travels along the fiber bouncing back and forth off of the boundary. Because the light must strike the boundary with an angle greater than the critical angle, only light that enters the fiber within a certain range of angles can travel down the fiber without leaking out. This range of angles is called the acceptance cone of the fiber. The size of this acceptance cone is a function of the refractive index difference between the fiber's core and cladding. In simpler terms, there is a maximum angle from the fiber axis at which light may enter the fiber so that it will propagate, or travel, in the core of the fiber. The sine of this maximum angle is the numerical aperture (NA) of the fiber. Fiber with a larger NA requires less precision to splice and work with than fiber with a smaller NA. Single-mode fiber has a small NA.

(Figure 2.4.7.1 Total Internal Reflection)

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2.4.8

Optical Fiber types

In graded-index fiber, the index of refraction in the core decreases continuously between the axis and the cladding. This causes light rays to bend smoothly as they approach the cladding, rather than reflecting abruptly from the corecladding boundary. The resulting curved paths reduce multi-path dispersion because high angle rays pass more through the lower-index periphery of the core, rather than the high-index center. The index profile is chosen to minimize the difference in axial propagation speeds of the various rays in the fiber. This ideal index profile is very close to a parabolic relationship between the index and the distance from the axis.

2.4.8.1 Multi-mode fiber Fiber with large core diameter (greater than 10 micrometers) may be analyzed by geometrical optics. Such fiber is called multi-mode fiber, from the electromagnetic analysis (see below). In a step-index multi-mode fiber, rays of light are guided along the fiber core by total internal reflection. Rays that meet the core-cladding boundary at a high angle (measured relative to a line normal to the boundary), greater than the critical angle for this boundary, are completely reflected. The critical angle (minimum angle for total internal reflection) is

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determined by the difference in index of refraction between the core and cladding materials. Rays that meet the boundary at a low angle are refracted from the core into the cladding, and do not convey light and hence information along the fiber. The critical angle determines the acceptance angle of the fiber, often reported as a numerical aperture. A high numerical aperture allows light to propagate down the fiber in rays both close to the axis and at various angles, allowing efficient coupling of light into the fiber. However, this high numerical aperture increases the amount of dispersion as rays at different angles have different path lengths and therefore take different times to traverse the fiber.

(Figure 2.4.8.1 Transmission through MMF)

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2.4.8.2 Single-mode fiberThe structure of a typical single-mode fiber consists of: 1. Core: 8 m diameter 2. Cladding: 125 m diameter 3. Buffer: 250 m diameter 4. Jacket: 400 m dia. Fiber with a core diameter less than about ten times the wavelength of the propagating light cannot be modeled using geometric optics. Instead, it must be analyzed as an electromagnetic structure, by solution of Maxwell's equations as reduced to the electromagnetic wave equation. The electromagnetic analysis may also be required to understand behaviors such as speckle that occur when coherent light propagates in multi-mode fiber. As an optical waveguide, the fiber supports one or more confined transverse modes by which light can propagate along the fiber. Fiber supporting only one mode is called single-mode or monomode fiber. The behavior of larger-core multi-mode fiber can also be modeled using the wave equation, which shows that such fiber supports more than one mode of propagation (hence the name). The results of such modeling of multimode fiber approximately agree with the predictions of geometric optics, if the fiber core is large enough to support more than a few modes. The waveguide analysis shows that the light energy in the fiber is not completely confined in the core. Instead, especially in single-mode fibers, a significant fraction of the energy in the bound mode travels in the cladding as an evanescent wave. The most common type of single-mode fiber has a core diameter of 810 micrometers and is designed for use in the near infrared. The mode structure depends on the wavelength of the light used, so that this fiber actually supports a small number of additional modes at visible wavelengths. Multi-mode fiber, by 57

comparison, is manufactured with core diameters as small as 50 micrometers and as large as hundreds of micrometers. The normalized frequency V for this fiber should be less than the first zero of the Bessel function J0 (approximately 2.405).

(Figure 2.4.8.2 Cross section of SMF)

2.4.8.3 Special Purpose Fiber Some special-purpose optical fiber is constructed with a non-cylindrical core and/or cladding layer, usually with an elliptical or rectangular cross-section. These include polarization-maintaining fiber and fiber designed to suppress whispering gallery mode propagation. Photonic-crystal fiber is made with a regular pattern of index variation (often in the form of cylindrical holes that run along the length of the fiber). Such fiber uses diffraction effects instead of or in addition to total internal reflection, to confine light to the fiber's core. The properties of the fiber can be tailored to a wide variety of applications.

2.4.9

Manufacturing Process

Standard optical fibers are made by first constructing a large-diameter preform, with a carefully controlled refractive index profile, and then pulling the preform to 58

form the long, thin optical fiber. The preform is commonly made by three chemical vapor deposition methods: inside vapor deposition, outside vapor deposition, and vapor axial deposition.

With inside vapor deposition, the preform starts as a hollow glass tube approximately 40 centimeters (16 in) long, which is placed horizontally and rotated slowly on a lathe. Gases such as silicon tetrachloride (SiCl4) or germanium tetrachloride (GeCl4) are injected with oxygen in the end of the tube. The gases are then heated by means of an external hydrogen burner, bringing the temperature of the gas up to 1900 K (1600 C, 3000 F), where the tetrachlorides react with oxygen to produce silica or germania (germanium dioxide) particles. When the reaction conditions are chosen to allow this reaction to occur in the gas phase throughout the tube volume, in contrast to earlier techniques where the reaction occurred only on the glass surface, this technique is called modified chemical vapor deposition. The oxide particles then agglomerate to form large particle chains, which subsequently deposit on the walls of the tube as soot. The deposition is due to the large difference in temperature between the gas core and the wall causing the gas to push the particles outwards (this is known as thermophoresis). The torch is then traversed up and down the length of the tube to deposit the material evenly. After the torch has reached the end of the tube, it is then brought back to the beginning of the tube and the deposited particles are then melted to form a solid layer. This process is repeated until a sufficient amount of material has been deposited. For each layer the composition can be modified by varying the gas composition, resulting in precise control of the finished fiber's optical properties.

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(Fig 2.4.9.1 Process Diagram of Manufacture of Fiber) In outside vapor deposition or vapor axial deposition, the glass is formed by flame hydrolysis, a reaction in which silicon tetrachloride and germanium tetrachloride are oxidized by reaction with water (H2O) in an oxyhydrogen flame. In outside vapor deposition the glass is deposited onto a solid rod, which is removed before further processing. In vapor axial deposition, a short seed rod is used, and a porous preform, whose length is not limited by the size of the source rod, is built up on its end. The porous preform is consolidated into a transparent, solid preform by heating to about 1800 K (1500 C, 2800 F). The preform, however constructed, is then placed in a device known as a drawing tower, where the preform tip is heated and the optic fiber is pulled out as a string. By measuring the resultant fiber width, the tension on the fiber can be controlled to maintain the fiber thickness. 60

2.4.10

Coatings

The light is "guided" down the core of the fiber by an optical "cladding" with a lower refractive index that traps light in the core through "total internal reflection." The cladding is coated by a "buffer" that protects it from moisture and physical damage. The buffer is what gets stripped off the fiber for termination or splicing. These coatings are UV-cured urethane acrylate composite materials applied to the outside of the fiber during the drawing process. The coatings protect the very delicate strands of glass fiberabout the size of a human hairand allow it to survive the rigors of manufacturing, proof testing, cabling and installation. Todays glass optical fiber draw processes employ a dual-layer coating approach. An inner primary coating is designed to act as a shock absorber to minimize attenuation caused by microbending. An outer secondary coating protects the primary coating against mechanical damage and acts as a barrier to lateral forces. Sometimes a metallic armor layer is added to provide extra protection. These fiber optic coating layers are applied during the fiber draw, at speeds approaching 100 kilometers per hour (60 mph). Fiber optic coatings are applied using one of two methods: wet-on-dry, in which the fiber passes through a primary coating application, which is then UV cured, then through the secondary coating application which is subsequently cured; and wet-on-wet, in which the fiber passes through both the primary and secondary coating applications and then goes to UV curing. Fiber optic coatings are applied in concentric layers to prevent damage to the fiber during the drawing application and to maximize fiber strength and microbend resistance. Unevenly coated fiber will experience non-uniform forces when the coating expands or contracts, and is susceptible to greater signal attenuation. Under proper drawing and coating processes, the coatings are concentric around the fiber, continuous over the length of the application and have constant thickness.

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Fiber optic coatings protect the glass fibers from scratches that could lead to strength degradation. The combination of moisture and scratches accelerates the aging and deterioration of fiber strength. When fiber is subjected to low stresses over a long period, fiber fatigue can occur. Over time or in extreme conditions, these factors combine to cause microscopic flaws in the glass fiber to propagate, which can ultimately result in fiber failure. Three key characteristics of fiber optic waveguides can be affected by environmental conditions: strength, attenuation and resistance to losses caused by microbending. External fiber optic coatings protect glass optical fiber from environmental conditions that can affect the fibers performance and long-term durability. On the inside, coatings ensure the reliability of the signal being carried and help minimize attenuation due to microbending.

2.4.11

Termination and Splicing

Optical fibers are connected to terminal equipment by optical fiber connectors. These connectors are usually of a standard type such as FC, SC, ST, LC, or MTRJ. Optical fibers may be connected to each other by connectors or by splicing, i.e., joining two fibers together to form a continuous optical waveguide. The generally accepted splicing method is arc fusion splicing, which melts the fiber ends together with an electric arc. For quicker fastening jobs, a "mechanical splice" is used. Fusion splicing is done with a specialized instrument that typically operates as follows: The two cable ends are fastened inside a splice enclosure that will protect the splices, and the fiber ends are stripped of their protective polymer coating (as well as the sturdier outer jacket, if present). The ends are cleaved (cut) with a precision cleaver to make them perpendicular, and are placed into special holders in the splicer. The splice is usually inspected via a magnified viewing screen to check the cleaves before and after the splice. The splicer uses small motors to align the end faces together, and emits a small spark between electrodes at the gap to burn off dust and moisture. Then the splicer generates a larger spark that raises the temperature above the melting point of the glass, fusing the ends 62

together permanently. The location and energy of the spark is carefully controlled so that the molten core and cladding do not mix, and this minimizes optical loss. A splice loss estimate is measured by the splicer, by directing light through the cladding on one side and measuring the light leaking from the cladding on the other side. A splice loss under 0.1 dB is typical. The complexity of this process makes fiber splicing much more difficult than splicing copper wire. Mechanical fiber splices are designed to be quicker and easier to install, but there is still the need for stripping, careful cleaning and precision cleaving. The fiber ends are aligned and held together by a precision-made sleeve, often using a clear index-matching gel that enhances the transmission of light across the joint. Such joints typically have higher optical loss and are less robust than fusion splices, esp