Network Fundamentals Part 3

- Copper

- Fibre

- Wireless

- Antenna Types

- Copper 10Base2/10Base5/xBaseT

- Fiber Optics

- Wireless

- Connectors

- Unshielded Twisted Pair Cable

- Coaxial Cable

- Shielded Twisted Pair

- Most common form of physical connection

- Twisted-pair cable mostly used LANs

- Flexible, fast, efficient

- 10Base-T

- Cable is unshielded

- All the wires are twisted through its entire length

- This reduces cross-talk and interference

- Shielded cables have an aluminium shield inside the plastic wire cover to stop outside interference on the copper cables

- More expensive than UTP

- Straight through, most common patch cable

- Connects a computer to a central connecting device

- 10Base2 Thinnet

- 10Base5 Thicknet

- Medium Dependent Interface Port

- Stops the need for wires having to cross to communicate

- Cutting Tool

- Wire Stripper

- Punch Down Tool

- Continuity Tester (Tests all of the pins one by one)

- Twisted-pair cables can be run 100m before the signal degrades

- Repeater, Hub or Switch can extend the signal

- Twisted-pair networks and all other networks can all be affected by interference from a signal that is traveling along a wire

- Electromagnetic Interference

- This is a disturbance of radiation and electromagnetic conduction affecting all types of electronic devices

- These cables should be kept away from these electrical devices whenever possible

- Radio Frequency Interference

- AM/FM Frequencies

- Electromagnetic field generated by a network cable or network device, which can be manipulated to steal data (hear conversations)

- Shielded Cabling or Run Cabling through metal conduits

- Can shield an entire server room "Faraday Cage"

- Interference that occurs when one signal is transmitted on one copper wire then affecting other wires in the vicinity

-

- NEXT : Near End Crosstalk interference closest to the transmitter

- FEXT : interference furthest from the transmitter

- Cables with this rating in case of a fire have a Teflon coating making them more impervious to fire

- Standard TPC have a PVC jacket which emit poisonous gas in fires

- 10Mbps

- 100Mbps + Gigabit Networks

- Gigabit Networks

- 10 Gigabit Networks

- RJ11

- RJ12

- RJ45

- 4 Pins

- Supports 2 Twisted Pairs

- Network communication and telephone wiring

- 6 Pins

- Supports 3 Twisted Pairs

- 8 Pins

- 4 Twisted pair cables

- Ethernet Cabling standard

- Connects a network host to a network device such as a switch or a hub

- Connects two network hosts

- Or Switch to Switch, Router - Router

- Connects a work station serial port to a console port using an adapter

- Primarily used on Thin Coaxial cabling (10Base2)

- T-Connector Barrel

- Resistor/Terminator

- N Type (joins them together)

- F Type mainly used for satellites, cable modems

- Transmits light (photons) instead of electricity

- Glass is considered the "media" of the cable

- Optical fiber that carries a single ray of light

- Long distance runs 10km up to 80km

- Laser as light source

- Shorter distances up to 600m

- 6x the distance of twisted-pair cable runs

- LEDs as light source

- Enterprise Networks

- (FTTH) Fiber to the home

- Long-Haul Networks

- Submarine Networks

- High Bandwidth

- Easily Increase Bandwidth

- Resistant to Electromagnetic Interference

- Early detection of cable damage and secure transmissions

- Costs still high

- Special test equipment required for maintenance

- Susceptibility to physical damage

- Wildlife damage to cables

- Multimode Orange

- Singlemode Yellow

- Straight Tip

- Subscriber Connector

- Local Connector

- Similar to SC connections

- Uses bayonet wire fitting

- Spring loaded

- Originally intended for Gigabit Ethernet

- Push-pull connector

- Wireless devices allow for central connectivity of client computers and handheld devices

- May be an extension of a network or may be the entire network

- WAP

- Router

- Firewall

- IP Proxy

External

- USB

- PC Card

- ExpressCard

Internal

- PCI or PCI express adapter

- Used to extend the coverage of a wireless network

- Bridge can connect 802.11 standards together

- These networks are Ethernet based, can be based off other networking architectures

- WEP

- WPA (TKI)

- WPA2

- WPA2 (AES)

- Designed to provide the same level of security as wired networks

- Difficult to configure

- Easily broken

- WPA Enterprise uses an authentication server to generate keys or certificates

- Security enhancement over WEP

- Temporal Key Integrity Protocol

- Changes the key for each packet so it is more difficult to hack

- More commonly used encryption is PSK: Pre Shared Keys

- 802.11i

- Several ways to connect to and are authenticated by WAP

- Ad-hoc Mode

- Infrastructure Mode

- All of the clients communicate directly with each other

- The clients on a network communicate directly with eachother

- Service Set Identifier

- Becomes the name of this wireless network

- Devices connecting to the WAP identify it through SSID