250 likes | 357 Views
BASIC TELECOMMUNICATIONS . PATCH CORDS. Telecom Cabling. Even with the advent and deployment of wireless technology, with its inherent problems of size, speed, and security Most people still feel more comfortable with hard-wired systems . Telecom Cabling. voice-telephone
E N D
BASIC TELECOMMUNICATIONS PATCH CORDS
Telecom Cabling • Even with the advent and deployment of wireless technology, with its inherent problems of size, speed, and security • Most people still feel more comfortable with hard-wired systems
Telecom Cabling • voice-telephone (including VOIP-voice over internet protocol) VONAGE • Data-computers, hubs, switches, routers • Video-CCTV-CATV • Security-both hard-wired and wireless • Fire- analog addressable systems • limited energy/Building Automation • POE-power over ethernet • Wireless-still need wires here!
Telecom Cabling • The typical buyer of a cabling system is an IT (information technology) or network manager . • Cabling represents only a few percent of their budget, yet it may cause half their problems! • Also, Electrical contractors, retailers, industrial, pharmaceutical, military, high tech • And many others……it is everywhere
Telecom Cabling • Most customers know very little about cabling. • What they do know is when it goes bad. • When they find a reliable cable company, they will treat them like gold and refer them to others • Most of our business is “word of mouth” • Always be aware of this!
Telecom Cabling • Low voltage work is rarely understood and more often times misunderstood. • This is good and bad. • Bad because we are neglected in the design phase and must struggle with poor design and lack of information. • Good because we can charge inflated prices for our expertise.
Telecom Cabling • It is still estimated, after all these years, that 70% of all network issues are cable related
Telecom Cabling 4 pair UTP, CAT 6 cable, todays preferred cable for high speed networks.
Telecom Cabling • Lets look at the first part of the basic network link. • Essentially a network is a system that links various devices. • your computer may be linked to other computers via cables. • The first cable you see is the Patch Cord connecting your PC to a wall outlet.
Telecom Cabling • CAT 5e network patch cables Notice the cable markings
Telecom Cabling • UTP stands for “Unshielded Twisted Pair”. This cable is unshielded, meaning there is no metallic shielding within the cable jacket and that the pairs of conductors inside the jacket are twisted. • The twisting of the conductors was an important break-thru in high speed data transmission. CAT 1 CAT 3 CAT 6
Telecom Cabling • There are some fundamental principles of electricity that occur in all cables. One is that when we apply voltage to a conductor a magnetic field will form around that conductor. • The other is that that if we place a conductor into a magnetic field, voltage will form on it and it will produce electricity.
Telecom Cabling • With telecom cables we are actually transmitting digital information in the form of current. • The digital language is a series of ones and zeros or on and off. These ones and zeros compose the language of the digital age. • Today we can transmit millions of these on-off signals per second with ease over copper.
Telecom Cabling • The inherent problem here is that when we transmit information using electricity on copper, the conductor makes a magnetic field around itself. • If another conductor is too close to the magnetic field, the field will INDUCE signal onto that conductor. • We call this EMI (Electro Magnetic Interference) and this is one our biggest enemies in cabling.
Telecom Cabling • It was discovered that by varying the twist rates of conductors, we could keep pairs of wires from “talking” to each other via magnetism. • This discovery allowed us to transmit electrical signals on several conductors at once resulting in fidelity of signal, larger carrying capacity, and greater speed.
Telecom Cabling • Today we use primarily the RJ-11 and RJ-45 plugs.
Telecom Cabling • The RJ-45 plug is an 8 pin unit meaning it can hold 8 conductors. It is used with 4 pair cable. • The plugs are “crimped” onto the conductors using the pressure of a crimp tool to cause to metal leads of the plug to displace the insulation of the conductors causing a metal to metal contact.
Telecom Cabling • The 8 conductors of the 4 pair cable are inserted into the modular plug in a particular order. This color sequence used for patch cords is primarily one of two standards. • T568A or T568B. With “T” indicating it is a “Termination “standard and not a Commercial Telecom standard (i.e. 568).
Telecom Cabling The two wiring schemes used in todays data networks
Telecom Cabling • Note that with the clip of the plug facing down there is a sequence we use to arrange the conductors before inserting them into the plug. • Pin numbers 4, 5, 7, and 8 always remain the same between the two standards and pins 1,2,3, and 6 change between the two. • CLUE: You can find the pin-outs listed on your 4-pair tester.
Telecom Cabling • If we make a patch cord that has the same standard used on both ends (A to A or B to B), then we have made a “straight-thru” patch cord. • If we make a cord using one standard on one end and another on the far end, then we have made a special cord called a “cross-over” cord.
Telecom Cabling • Eventually, our patch cords are used to an electronic device called a switch or hub. • The type of cord we use tells the switch what type of device is plugged into it and that tells the switch how much digital space to make available to that device.
Telecom Cabling • We use straight-thru cords to connect devices such as PC’s, cameras, wireless access points to the cabled infrastructure and we use X-over cords to connect switches to switches or routers.
Telecom Cabling When configuring your wireless router to network a PS3 or X-Box game system, should you use a 568A or 568B patch cord?
Telecom Cabling • This slide intentionally left blank. End day one.