IP - Internet Protocol

• The basic protocol that instructs us on how almost all communication across internet networks must be implemented.

• Messages over IP are often communicated in "packets",

  • which are small bundles of information (2^16 bytes).

  • Each packet has an essential structure made up of two components: the Header and the Data.

• Header

  • Contains "meta" data about the packet and its data.

  • his metadata includes information such as

    • the IP address of the source (where the packet comes from)

    • the destination IP address (destination of the packet).

• an IP Address

  • layer 3 property

  • Has Network and Host portion

  • is a numeric label assigned to each device connected to a computer network that uses the Internet Protocol for communication

  • There are public and private IP addresses,

  • there are currently two versions.

    • IPv6 and is increasingly being adopted because IPv4 (4 bytes = 32 bits) is running out out numerical addresses.

• other protocols are built on top of IP,

  • like frameworks built on languages

• Network vs Host

  • a.b.c.d/x

    • a,b,c,d are integers

    • x = defines the network, and the rest as host

  • Example: 192.168.254.0/24

    • the first 24 bits (3 bytes) are network

      • Max number of networks 2^24 and 2^8 hosts

    • the rest 8 bits are for host

    • subnet

      • subnet has a mask ie 255.255.255.0

      • used to determin if IP is in same subnet

• Default Gateway

  • Most networks consist of hosts and a default gateway

  • when host A want to talk to B directly if both are inthe same subnet, thus use mac address

    • OW A sends it to someone who might know the gateway

  • Has an IP add and each host should konw it's gateway

• https://youtu.be/o5S0-_vniiM The Beauty of the Internet Protocol hassan nasser