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

NAT

Network Address Transalation
Allows a gateway, router, firewall, to rewrite the source IP of an outgoing IP datagram while retaining the original IP in order to rewrite it into the response.
images/15-1.png
Soo basically the NAT hides the IP of Computer 1 from Computer 2, even while able to send data from computer 2 to 1 for a response
IP masquerading
This /|\ above mentioned is a ONE to MANY NAT.

NAT AND TRANSPORT LAYER:

Port Preservation :
A technique where the source port chosen by a client is the same port used by the router.
images/15-2.png


Port Forwarding :
A technique where specific destination ports can be configured to always be delivered to specific nodes.
images/15-3.png


REGIONAL INTERNET REGISTRY
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