MultiCloud Classroom notes 21/Feb/2024

IP v4 Address

• Unique number given to a device on a network.
• IPV4 is a 32 bit number which is grouped into 4 octets (8 bits)

X.X.X.X

X = octet
  = 8 bits
  = 2^8
  = 0 to 2^8-1
  = 0 to 256 - 1
  = 0 to 255

• Range of IPv4

0.0.0.0 to 255.255.255.255

• Ip Address: i have asked for ip address and i got
  • subnet mask
  • default gateway
    
• IP Address = network id + host id
• Network id is same for the entire network i.e. it is fixed
• host id represents a host in a network. number of unique host ids we can have defines size of the network.
• In every network we can use two ips i.e. (all zeros and all ones)
  • all zeros => network id
  • all ones => broadcast id

192.168.0.10

• To figure out the network id from ip address we need subnet mask

ip: 192.168.0.10
sm: 255.255.255.0
--------------------
    192.168.0         => network id
               10     => host id
                      octects for host id = 1 = 8 bits = 2^8  
                      size = 2^n - 2
                            = 2^8 - 2
                            = 256 -2 
                            = 254
                      192.168.0.xxxxxxxx
                      192.168.0.0 => network id
                      192.168.0.255 => broadcast id

ip: 10.10.0.11
sm: 255.255.0.0
---------------------
    10.10             => network id
           0.11       => host id 
                      => host id size = 2 octects = 2 * 8 = 16
                      size = 2^16 - 2
                           = 65536 -2
                           = 65534

ip: 10.0.0.8
sm: 255.0.0.0
--------------------
     10              => network id
        0.0.8        => host id
                     => size = 3 octects = 3*8
                     size = 2^24-2
                        = 16777216 - 2
                          16777214 

• Exercise

network 1
ip: 172.16.0.9
sm: 255.255.0.0
---------------------
nid: 172.16
hid:        0.9
size = 2 * 8 = 16 => 2^16-2 = 65534


network 2
ip: 172.16.0.9
sm: 255.255.255.0
---------------------

size = 2^8-2 = 254

• We have 3 possibilities:
  • 1 octet ~= 250
  • 2 octet ~= 65000
  • 3 octet ~= 16777214
• To design network we have two ip addressing strategies
  • Classful Network
  • Classless Networks (CIDR classless inter domain routing)
    • start looking at subnet masks as binaries rather than octets
    • private networks:
      • this is not directly acessible from internet
      • duplicates are allowed i.e your network and other network might have same range.
      • all private networks will be in the following ranges
        • 192.168.0.0 to 192.168.255.255
        • 10.0.0.0 to 10.255.255.255
        • 172.16.0.0 to 172.31.255.255
    • public networks:
      • this is accessible directly from internet
      • duplicates are not allowed

Activity 1:

• Refer Here for 2 power table
• I want to create a network of 300 devices what would be subnet mask

2^n -2 ~= 300

2^n ~= 300

n = 9
host bits (n) = 9
network id bits (N) = 32 - 9 = 23

SM: 11111111.11111111.11111110.00000000  => 255.255.254.0

• I want to create a network of 10000 devices what would be subnet mask

2^n ~= 10000
host bits (n) = 14
Network id bits (N) = 32 - 14 = 18
SM: 11111111.11111111.11000000.00000000 = 255.255.192.0

• I want to create a network of 50 devices what would be subnet mask

2^n ~= 50
host bits (n) = 6
Network id bits (N) = 32 - 6 = 26
SM: 11111111.11111111.11111111.11000000 = 255.255.255.192

• I want to create a network of 300000 devices what would be subnet mask

2^n ~= 300000
host bits (n) = 19
Network id bits (N) = 32 - 19 = 13
SM: 11111111.11111000.00000000.00000000 = 255.248.0.0