Transcript Cisco – Semester 1 – Chapter 9

Cisco – Semester 1 – Chapter 9
Preview
Review
Behavioral Objectives
• Document all work
– Do it as work proceeds
– Same as chapter 8 guidelines
– Don’t forget journals
• Develop Planning Mentality
– Create flow chart to guide work
– Get permissions and materials before work begins
• Respect Do’s and Don’ts for installing network
media
Learning Objectives
• Use correct installation procedures for
network media
– Maximizes network performance
• Follow established safety procedures when
installing network media
– Protect yourself and others
• If you learn nothing else, learn this
–Turn power off before you begin
Networking Media
• Foundation of OSI Model
• Most Important Component of OSI model
• RJ 45 Jack Recommended by TIA/EIA
– Wiring Sequence is critical for optimum
network performance
Documentation
• Use cut sheet
– Rough diagram
• Location of Cable runs, rooms, etc.
• Record same data in journal
• Label hardware termination units
– UL969 states labels must adhere, be legible,
and should discourage defacement. Labels
should be mnemonic
Flowchart Elements
• Install outlets, jacks, NICS, hubs, switches, routers
(document as you proceed)
• Install Patch panels and test
• Run and test cables (document as cables are run
and tested)
• Configure router(s)
• Install and configure PCs
• Document everything
Know About and Use as
Reference
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OSHA Codes
Building Codes (State and Local)
Electrical Codes (TIA/EIA, UL)
Network Media Standards (IEEE, ISO/IEC)
Wiring Closet Devices
• Patch Panel (Layer 1)
• Hubs - (can act as a switchboard
interconnect); connects computers and other
devices (Layer 1)
• Bridge – Layer 2 – filters traffic
• Switch – Layer 2 – filters and routes traffic
• Routers – Layer 3 – segments network –
reduces broadcast domain
TIA/EIA Standards
• Must use RJ-45 jack to connect CAT 5 UTP
• May use flush or surface mount for jack
– Surface mount may be screw mount or adhesive
• Concerns:
– At least 5 cm (2 inches) from bottom of
baseboard (otherwise wall plate may interfere)
– Avoid door and window trim
Importance of Patch Panels
• Key component of structured cabling
• Allow cables to be terminated in organized
yet strong and flexible manner
• Cabling standards call for installation in
certain areas of cable run – MDF and IDF
Labeling Standards
• UL 969
– Must meet standards including:
• Legibility
• Defacement
• Adhesion
Cabling Procedures
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Label the Boxes and Cable before you start
Dress the Cable
Secure the Cable with Ties or Bars
Install Wire Management Panels
Cabling Dos
• Use cable ties to hold cables together
• Strip back only sheathing that you need
(maximum exposed is 1.3 centimeters or .5 inch
• Keep bend radii to less than 4 times diameter of
cable
• Provide extra cable at ends (leave a service coil)
• Use cable support bars, management panels,
velcro straps, and ladder racks)
• Label cable runs
• Use Punch Down tool correctly (cut blade away
from you)
Cabling Don’ts
• Don’t untwist wires – twisting is important
for cancellation effect
• Don’t stretch wire (causes untwisting)
• Don’t bend cable – never beyond right
angle
• Don’t twist cable jacket (no kinks)
• Don’t use a staple gun
Rules for Cable Spools
• Leave in box
• Don’t unwind
• Don’t cut cable unless labeled – at least
three times at intervals
• Do bind cable ends to pull as a unit
Testing
• Functional Test – plug in computer and see
if you can make an outside connection to
WWW
• Use a cable tester (preferred method)
Problems
• Connectors are weakest Link
– Attach CAT5 at Patch Panel in ascending order; labels
should correspond to rooms
– Keep ends centered above pin locations
– Keep jacket within 6.4 mm of pin locations
– Don’t untwist wire pairs more than necessary
– Use Krone or 110 punch – depends on patch panel
• Mount Patch Panel to wall, rack, or place in
cabinet
Other Problems
• Split Pairs – wire from one circuit crossed with
wire from another circuit(can’t be detected with
wire map) find by visual inspection and cross talk
measurement (is a result of wires not being part of
same circuit – did not follow wire map) – result
will be near end cross talk
• Cross Talk – crossed pairs(can be detected visually
and wire map) and with cable meter
• EMF – unplug electrical devices (one at a time)
and measure attenuation with cable tester
Outside Problem Sources
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Fluorescent lights
Heaters
Radios
Air cleaners,
TVs
Computers
Motors, Switches, Welders
Tools
• Signal Injector – put at end of cable to measure
reduction in power of signal
• Cable Tester aka Time Domain Reflectometer–
(high number is good; low number problem)
measures:
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Signal attenuation
Near End Cross Talk
Distance
Bad connections
Crossed pairs
• Can trace noise behind wall & measure noise