Chapter 4 – Cisco Semester I

1. Chapter 4 – Cisco Semester I Wiring Closets IDF and MDF Metrics

2. Behavior Objective • Stress importance of good documentation • Stress adherence to wiring Do’s and Don’ts • Students will document work • Students will follow standard procedures

3. Learning Objective • Develop knowledge base to enable students to design networks that perform well Students will learn design concepts Students will gain confidence completing wiring tasks

4. Content • Network Design • Topologies • Logical • Token Ring (single ring) • FDDI (dual ring) • Ethernet (logical bus) – largest % of installations • Physical • Star and Extended Star • Both Ethernet and IEEE specify Star • Extended Star requires additional wiring closets

5. Content Continued • Wiring and electrical standards • ANSI • EIA/TIA 569-A • ISO/NEC • Wiring closet specifications • Medium • CAT 5 UTP for horizontal cabling

6. Why CAT 5 UTP • Easy to use (not too thick but thick enough to hold up – unlike cheap net) • Twists provide cancellation effect • Relatively inexpensive • Specified by both IEEE and Ethernet

7. Ethernet Network Speeds • 10Base T • 100 Base TX (aka Fast Ethernet) • 1000 Base T (aka Gigabit)

8. Documentation Required • Organization Information • Who will use, computer skill level, network knowledge base, tasks performed • Analysis and Problem Solving Information Gathered • Cut Sheet – diagram floor plans • Logical Design Map – IP addresses • Physical Design Map – MAC addresses (devices), cable runs, outlets, etc.

9. DEVICES • Layer 1 • Hubs, repeaters (extend run beyond 99 meters) • Transceivers – connect unlike devices • Layer 2 • Bridges -- reduce congestion and collision domain • Switches – also provide virtual LAN and larger bandwidth • Layer 3 • Routers – segmentation – divide network into segments; reduce broadcast domain

10. Ground Basics • Grounds are critical • Can minimize ESD problem • Remember ESC can destroy semiconductors and data • Safety ground can prevent high voltage buildup • GFCI (Ground Fault Circuit Interrupt)can cause circuit breaker to stop flow of electrons • Grounds connected to chassis are not enough to protect computers and networks • Also need UPS (Uninterrupted Power Supply) • And Surge Protector

11. Wiring Basics • One Hand Rule • Keep one hand in pocket when working with electrical devices to avoid creating a circuit with your body as the connection • Electrical Current through the heart can kill • Common Fault • Hot Wire and Safety • Normal Fault • Hot Wire and Neutral Wire

12. Wiring Closet Specifications • Near POP – to connect to outside world • Centrally located – to minimize length of horizontal cable runs • More important than being near POP • Large enough to allow for expansion • Raised floor • To bring in horizontal cabling from work areas

13. Wiring Closet Continued • Tile Floor • Reduce dust, minimize static electricity • No Dropped Ceiling • Security • Fire-Rated Plywood on Interior Walls • Minimize fire risk (1.9 cm thick – 4.4 cm from wall) • Controlled Humidity (30-50%) • Controlled Temperature (21 C or 70 F)

14. More Wiring Closet Specs • .9 Meter door that opens to hall • Locked from outside but controlled from inside • 50 candle foot lighting (preferably not fluorescent) – 2.6 meters above floor • Light switch immediately inside door • Two dedicated non-switched circuits • Outlets every 1.8 meters (6 feet)

15. And Still More Closet Specs • Ladder Rack to support Patch Panel • Sufficient Floor Load capacity to bear weight of devices • Ceiling and wall openings sealed with fire retardant material

16. Important Wiring Closet Info • Need a wiring closet on every floor • Need a wiring closet for every 1000 square meters of floor space • Maximum length of horizontal cabling is 90 meters • Add 3 meters to attach work station and 6 meters to attach to patch panel • Total length – approx 100 meters

17. Multiple Wiring ClosetsStructured Wiring • Designate primary wiring closet as MDF – Multiple Distribution Facility • Hubs and Patch Panel in MDF or IMF • Routers, switches, WAN connection in MDF • Floor load requirements higher than IDF • Vertical cabling (Backbone) will connect other wiring closets (IDF – Intermediate Distribution Facility)

18. MDF and IDF Location • Good location can minimize horizontal cable runs • Chosen location should minimize environmental problems • Chosen location should make it easy to install and maintain network

19. Structured Wiring • MDF known as Main Cross Connect • Can have two levels of IDF (Intermediate) • When there is only one level • IDF Horizontal Cross Connect • When there are two levels • IDF connected to MDF is Intermediate Cross Connect • Other IDFs connected to workstations are HCC • There can be only one level between IDF for work stations and MDF

20. MDF – IDF Cabling • Aka Backbone Cabling Between Buildings (InterBuilding) -- Single Mode Fiber preferred – 3000 meters Within Building (Intrabuilding) MultiFiber 62.5/125 u is recommended (568A) – 2000 meters – USED MOST OFTEN Other options (not preferred and not extensively used) 100 ohm UTP (four pair) 150 ohm STP (two pair) Coaxial cable is not recommended

21. Why Fiber for Backbone? • Eliminates Problems Caused By: • Different Voltage Potential in circuits served by different transformers (a grounding problem) • Different transformers can serve circuits in same building • Electrical strikes that could hit cabling between buildings • Backbone includes connection to POP and Wiring Closets (from Patch Cords)

22. Special Backbone Considerations • Run wire through conduit or sleeve • If unable to run under floor • Run sleeve above door level • Total distance from MDF to workstations can’t exceed 3000 meters for single mode or 2000 for multimode fiber

23. Metric Reminder • 1 Meter is approximately 39.?? Inches • 1 decimeter = 1/10 meter • 1 centimeter = 1/100 meter • 1 millimeter = 1/1000 meter • 10 meters = 1 decameters • 100 meters = 1 hectometer • 1000 meters = 1 kilometer