Institute of Technology Sligo - Dept of Computing Chapter 8 Network Design and Documentation.
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Transcript of Institute of Technology Sligo - Dept of Computing Chapter 8 Network Design and Documentation.
Institute of Technology Sligo - Dept of Computing
Chapter 8Chapter 8
Network Design Network Design and and
DocumentationDocumentation
Institute of Technology Sligo - Dept of Computing
In previous chapters you learnedIn previous chapters you learned: :
•OSI model and data encapsulation process .
•Different LAN technologies.
•Layers 1 & 2 concepts and technologies.
In this chapter you will start learning network design and documentation
Institute of Technology Sligo - Dept of Computing
GENERAL DESIGN PROCESSGENERAL DESIGN PROCESS
Network design takes into consideration
the following LAN technologies:
• Token-Ring
• FDDI
• Ethernet (focus of the curriculum)
Institute of Technology Sligo - Dept of Computing
• Ethernet has
- logical bus topology which leads to:
Collision domains;
- Your responsibility is to minimize them by:
segmentation
•Once you have chosen Ethernet technology
you must develop:
Institute of Technology Sligo - Dept of Computing
Step 1:Step 1:
•Layer 1 topology:
- Type of cable (most common is CAT 5)
- Physical topology (extended star)
- You may need to use hubs, repeaters,
transceivers and other layer 1 components
- Which type of Ethernet to be used:
10Base-T or 100Base-TXLayer 1 design finished with physical & logical topologies designed.
Institute of Technology Sligo - Dept of Computing
Step 2:Step 2:
•Layer 2 design:
-implementation of switches to reduce collision
domain size.
- VLAN design (sem- 3).
-replacing hubs with switches for existing
devices.
Institute of Technology Sligo - Dept of Computing
Step 3:Step 3:
•Layer 3 design:
- layer three devices (routers) to access
WAN services & internet.
- or you may need routers to segment
broadcast domains & to add more security
between different network segments.
Institute of Technology Sligo - Dept of Computing
Network design issuesNetwork design issues
•First step in the design process is
- to gather information about the organization:
- Users requirements
- types of applications
- projected growth
- operating policies & procedures
- people who will be using the network
Institute of Technology Sligo - Dept of Computing
•Second step
- Detailed analysis of gathered data: For example:
* Based on user requirements, numbers of users, and applications types you can determine:
- type of H/W : hubs, switches, type of H/W : hubs, switches, vlans; vlans;
* Based on projected growth, you may determine the scalability of your network:
- number of switches in MDF and/or IDF
- types of horizontal & backbone - types of horizontal & backbone cablingcabling
- bandwidth per user : 10, 100 - bandwidth per user : 10, 100 MBS;MBS;
Institute of Technology Sligo - Dept of Computing
- Number and speed of ports per switch / hub
- number and speed of ports to be used for backbone interconnections
* Based on type of applications you may determine:
- to divide users into groups in order to implement VLANs
- placement of servers:
- bandwidth per each user/group of users.
some applications are accessed by all users (DNS, E-Mail,…..), other applications are specific (financial, video training,…)
Institute of Technology Sligo - Dept of Computing
•Third step
- identify resources & constraints of the
organization:
- existing computer H/W
- existing S/W resources
- human resources
- organization’s budget
Institute of Technology Sligo - Dept of Computing
Engineering journal.Engineering journal. Logical topology.Logical topology. Physical topology. Physical topology. Cut sheets.Cut sheets. Problem-solving matrices. Problem-solving matrices. Labeled outlets. Labeled outlets. Labeled cable runs. Labeled cable runs. Summary of outlets and cable runs. Summary of outlets and cable runs. Summary of devices, addresses. Summary of devices, addresses.
- During your network design you will create the following documents:
Institute of Technology Sligo - Dept of Computing
Institute of Technology Sligo - Dept of Computing
Institute of Technology Sligo - Dept of Computing
Institute of Technology Sligo - Dept of Computing
Institute of Technology Sligo - Dept of Computing
Institute of Technology Sligo - Dept of Computing
Institute of Technology Sligo - Dept of Computing
Planning structured cablingPlanning structured cabling : :
wiring closet specificationswiring closet specifications
Institute of Technology Sligo - Dept of Computing
Overview of wiring closetOverview of wiring closet
- Selection of wiring closets (MDF/ IDF) according to standards.
One of the early decisions is:One of the early decisions is:
- MDF is where many of networking devices and cables will be installed
Institute of Technology Sligo - Dept of Computing
Cabling standardsCabling standards
Institute of Technology Sligo - Dept of Computing
• Services as a central point of a star Services as a central point of a star topology (TIA/EIA 568A standard)topology (TIA/EIA 568A standard)
• Where the horizontal cabling runs Where the horizontal cabling runs must be attachedmust be attached
• Where the patch panels and Where the patch panels and switches/ hubs must be installed.switches/ hubs must be installed.
Wiring closet specificationsWiring closet specifications::
• Must be large enough to accommodate Must be large enough to accommodate equipment and extra space for future equipment and extra space for future growth:growth:
Institute of Technology Sligo - Dept of Computing
Institute of Technology Sligo - Dept of Computing
•Each floor must have at least one wiring Each floor must have at least one wiring closetcloset•One wiring closet should be added for One wiring closet should be added for each 1000 each 1000 m2 or the horizontal cable or the horizontal cable distance exceeds 90m.distance exceeds 90m..
Institute of Technology Sligo - Dept of Computing
Environmental specificationsEnvironmental specifications
Materials for walls, floors, and Materials for walls, floors, and ceilings. ceilings.
Temperature and humidity. Temperature and humidity. Locations and types of lighting. Locations and types of lighting. Power outlets.Power outlets. Room and equipment access. Room and equipment access. Cable access and support. Cable access and support.
Selected room/ closet should satisfy certain requirements for:
Institute of Technology Sligo - Dept of Computing
20mm plywood that is at least 2.4m
Minimum load capacity.Raised floor or Ladder Rack Support.Tiled, or some other type of finished surface.
Rooms must not have a dropped, or false, ceiling
•Walls , floors and ceiling
Institute of Technology Sligo - Dept of Computing
- Temperature: 21- Temperature: 21oo..
- - humidity: 30 – 50%.humidity: 30 – 50%.
•VHAC
•Lighting and power outlets:
- No water or steam pipes running through or above the room.
- minimum of two dedicated, non - switched, AC duplex electrical outlets.
Institute of Technology Sligo - Dept of Computing
- At least one duplex power outlet positioned every 1.8 m along each wall..
- power outlet should be positioned 150 mm above the floor.
- main lighting control switch should be placed immediately inside the door
- florescent lighting should be avoided for cable pathways.
Institute of Technology Sligo - Dept of Computing
•Room and equipment access:- door should be at least 0.9 m wide;- door should open out of the room;- switches/ hubs and patch panel may be mounted:
- to wall using hinged wall bracket;
- with distribution rack;
Institute of Technology Sligo - Dept of Computing
Institute of Technology Sligo - Dept of Computing
Wiring hub and patch Wiring hub and patch panel were mounted to panel were mounted to a wall with a hinged a wall with a hinged wall bracket.wall bracket.
Wiring hub and patch panel were mounted with distribution rack
Institute of Technology Sligo - Dept of Computing
Institute of Technology Sligo - Dept of Computing
- All horizontal cabling that runs from work areas to a
wiring closet should be run under a raised floor;
- When this is not possible, the cabling should be run through 10.2 cm sleeves that are placed above door level.
- any wall/ ceiling openings should be sealed with a smoke and flame-retardant materials
Institute of Technology Sligo - Dept of Computing
Wiring closet identificationWiring closet identification
Institute of Technology Sligo - Dept of Computing
- You may think of a hub as a central point of a circle which has horizontal cables radiating from it.
Institute of Technology Sligo - Dept of Computing
• In order to determine the location of wiring In order to determine the location of wiring closet begin by drawing the floor plan;closet begin by drawing the floor plan;
•Add devices that will be connected to network;Add devices that will be connected to network;
• identify secure locations to be used as MDF/IDF;identify secure locations to be used as MDF/IDF;
• MDF should be close to the POP;MDF should be close to the POP;
• determine number of wiring closets;determine number of wiring closets;
Institute of Technology Sligo - Dept of Computing
Institute of Technology Sligo - Dept of Computing
• draw circles of radius 50 m from each potential draw circles of radius 50 m from each potential wiring closet (hub location)wiring closet (hub location)
• if there are any potential wiring closets whose if there are any potential wiring closets whose catchments areas substantially overlap, you may catchments areas substantially overlap, you may eliminate one of them.eliminate one of them.
• if the catchment area does not cover all devices, if the catchment area does not cover all devices, repeaters are used (IDF).repeaters are used (IDF).
Institute of Technology Sligo - Dept of Computing
Institute of Technology Sligo - Dept of Computing
Institute of Technology Sligo - Dept of Computing
MDF location in multi-story buildingMDF location in multi-story building
MDF is located on one of the middle floors, even though the POP might be located on the first floor.
Institute of Technology Sligo - Dept of Computing
MDF location in multi-building campusMDF location in multi-building campus
Institute of Technology Sligo - Dept of Computing
Backbone cabling consists ofBackbone cabling consists of::
• Backbone cabling runs•Intermediate and main cross-connects.
•Vertical media between wiring closets on different floors.•networking media between MDF and POP.•Networking media used between buildings in multi-building campus.
•Patch cords used for backbone – to –backbone cross – connection:.
Institute of Technology Sligo - Dept of Computing
Institute of Technology Sligo - Dept of Computing
Backbone cabling mediaBackbone cabling media
- 100 UTP (four – pair).
•According to TIA/EIA 568 A, four type of networking media can be Used for backbone cabling:
- 150 STP (two – pair).
- multimode optical fiber
- single mode optical fiber.
Institute of Technology Sligo - Dept of Computing
•IDF can be connected to MDF in two ways:IDF can be connected to MDF in two ways:
1. IDF can be connected directly to MDF
Institute of Technology Sligo - Dept of Computing
2. 1st IDF connected to 2nd IDF; the 2nd is then connected to MDF;
Institute of Technology Sligo - Dept of Computing
• No work areas are connected to ICC;• No more than one ICC can be passed through to reach MDF
Institute of Technology Sligo - Dept of Computing
•Maximum distance for backbone cabling:Maximum distance for backbone cabling:
Institute of Technology Sligo - Dept of Computing
Institute of Technology Sligo - Dept of Computing
Institute of Technology Sligo - Dept of Computing
Electricity and GroundingElectricity and Grounding
Institute of Technology Sligo - Dept of Computing• DC current flows in a constant value Examples: flashlight, car battery, computer motherboard
Institute of Technology Sligo - Dept of Computing
Institute of Technology Sligo - Dept of Computing
• AC noise all around us: in walls, ceilings, floors
• AC noise can come from: - from video monitors, H/D drives
•AC noise:AC noise:
Institute of Technology Sligo - Dept of Computing
•Electrostatic static discharge (ESD) Electrostatic static discharge (ESD)
• Static electricity: stationary electrons.
• Most damaging and uncontrollable Form of electricity.
• ESD destroy semiconductors and data.
• A solution that can help solve ESD problem: good grounding.
Institute of Technology Sligo - Dept of Computing
•Safety ground Safety ground
Institute of Technology Sligo - Dept of Computing
• Safety ground wire is connecting to any exposed metal of the equipment
• Motherboards and computing circuits in computers are connected to chassis this connects them to safety ground.
• Safety ground prevents metal parts from becoming energized.
• It serves as a low resistance path to the earth when a faulty connection between a hot line and chassis occurs.
Institute of Technology Sligo - Dept of Computing
•Multi-ground connectionsMulti-ground connections
• Large buildings frequently require more than one earth ground.
• Separate earth grounds also required in multi-building campus.
• Earth grounds between buildings is almost never the same. Also separate earth grounds for the same building may vary.
Institute of Technology Sligo - Dept of Computing
• When separate ground wires have different potential (voltage) to the common and hot wires they can present a serious problem
• If a circuit is established between devices in two buildings, then a current Would flow from negative to positive Source
• Such circuit could cause a nasty shock, and it may damage memory chips.
Institute of Technology Sligo - Dept of Computing
Institute of Technology Sligo - Dept of Computing
• A good way to avoid current pass through the body, and through the heart, is to use one hand rule.
•Avoiding dangerous circuits between buildingsAvoiding dangerous circuits between buildings
• TIA/EIA-568- standards recommends the use of optical fiber for backbone connections (between buildings, and between different floors within the same building.
• Optical fiber is a good insulator: Electricity does not travel over fiber.
Institute of Technology Sligo - Dept of Computing
Network power supply issuesNetwork power supply issues
Institute of Technology Sligo - Dept of Computing
•Power problem classificationPower problem classification
Institute of Technology Sligo - Dept of Computing
• Normal mode problem:
- don’t pose a hazard to you or to your computer .
• Common mode problem:
- Can go directly to computer’s chassis, they can damage data signals.
Institute of Technology Sligo - Dept of Computing
•Typical Power line problems:Typical Power line problems:
• Sag (brownout):
- short term decrease in voltage level
- duration : less than a second
- cause: equipment startup (motors, elevators)
-effects: lost or corrupted data, shrinking
screen, equipment shutdown
Institute of Technology Sligo - Dept of Computing
- Possible solutions:
-relocate a computer to a different electrical
circuit.
- voltage regulators.
- UPS.
Institute of Technology Sligo - Dept of Computing
Institute of Technology Sligo - Dept of Computing
• Total power loss:
- cause: excessive demand on power grid.
-Lighting storms.-Ice on power lines
-Car accidents
- effects: system shutdown.
- Possible solutions:
- UPS.
Institute of Technology Sligo - Dept of Computing
Institute of Technology Sligo - Dept of Computing
• Spike:
- instantaneous increase in voltage (microseconds).
-cause: nearby lighting strike, equipment cycle
on or off.
- effect: hardware damage, lockups, data loss.
Solution:
-surge suppressors
Institute of Technology Sligo - Dept of Computing
Institute of Technology Sligo - Dept of Computing
• surge:
- a short term increase in voltage (a few seconds)
-cause: high- powered electrical devices is
switched off.
-effects:hardware damage, lockups, data loss
Solution:
-surge suppressors.
Institute of Technology Sligo - Dept of Computing
Institute of Technology Sligo - Dept of Computing
• Oscillation (harmonics or noise):
-unwanted electrical signal of high frequency
form other equipment (RFI, EMI).
Institute of Technology Sligo - Dept of Computing
Solution:
-shortening power cable runs.-power line filtration.
- cause: lighting, generators, radio transmitters,
-disrupts the smooth sine wave expected from
utility power.
excessively long electrical wiring run.
- effects: data loss, errors.
Institute of Technology Sligo - Dept of Computing
Institute of Technology Sligo - Dept of Computing
• UPS
- sag and brownout problems best addressed by UPS.
- At minimum, every network file server
should have a UPS.- Where possible a power backup
should be provided for all work areas.
Institute of Technology Sligo - Dept of Computing
1. Standby (off-line or switched) ups
Types of UPS:
2. On-line (continuous) UPS.
3. Line-interactive UPS.
Institute of Technology Sligo - Dept of Computing
Institute of Technology Sligo - Dept of Computing
Good Luck !