Index

COMPUTER NETWORKING

  1. INTRO
    1. TCP/IP Five Layer Model
    2. NETWORKING DEVICES
    3. PHYSICAL LAYER
    4. DATALINK LAYER
  2. NETWORK LAYER
    1. IP
    2. SUBNET
    3. ROUTING
  3. TRANSPORT & APPLICATION LAYER
    1. TRANSPORT LAYER
    2. CONTROL FLAGS
    3. APPLICATION LAYER
    4. ALL TOGETHER
  4. NETWORK SERVICES
    1. DNS - NAMES RESOLUTION
    2. DHCP
    3. NAT
    4. VPN
  5. CONNECTING TO INTERNET
    1. BROADBAND
    2. WAN
    3. WIRELESS NETWORKING
  6. TROUBLESHOOTING
  7. MORE ABOUT
    1. DNS
    2. IPv6
    3. CLOUD

PHYSICAL LAYER

Moves ones and zeroes from one end to another.
Transports bits -> 1 or 0

Modulation : A way of varying the voltage of the charge moving across the cable. Line Coding.
1 and 0 are understood thru these modulations

10 Billion 1 and 0 across a single network cable every second.
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Twisted pair cable : Pairs of copper wires. protects against electro magnetic interference. single conduit. avoid crosstalk.
Cat6 - 8wires

Duplex Communication : The concept that information can flow in both directions across the cable.
One pair for one direction and another

FULL DUPLEX
HALF DUPLEX
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RJ45 network : registered jack ,plug - start ,end point (most common)
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Ports : Directly attached to devices that make up a computer network. Plugs connect here

Switches have many ports
Desktops : 1

Two small leds
Link light : Cable is properly connected
Activity light : Data transmission was active

Patch Panel : Contains many network ports
Ports : Directly attached to devices that make up a computer network
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