Dotted Decimal Notation Quick Draw IP Address Network bits This is the total number of networks you can have per CIDR or Dotted Decimal Networks per Subnet 2 4 8 16 32 64 128 256 Dotted Decimal Notation 192 224 240 248 252 254 255 Hosts Per Subnet: Class C 1 Class A /9 /10 /11 /12 /13 /14 /15 /16 Class B /17 /18 /19 /20 /21 /22 /23 /24 Class C /25 /26 /27 /28 /29 /30 /31 /32 Dotted Decimal Notation From the host bit take the Left most value, put it in dotted decimal spot, than take that number add it to the next host bit ex 128+64= 192, than add 192+32=224 and so on HOST Bits Double Numbers from right to left starting at 1 CIDR Each row represents 8 binary bits, allowing you to see the Class breakdown Base Exponent: In binary, you can determine number if

Host bits start in the second Octet Default Subnet Masks Networks per Subnet 2 4 8 16 32 64 128 256 Dotted Decimal Notation 192 224 240 248 252 254 255 Hosts Per Subnet 1 11111111.00000000.0000000.0000000 Network.Host____.Host____.Host 255.0.0.0 Class A /9 /10 /11 /12 /13 /14 /15 /16 11111111.11111111.00000000.0000000 Network.Network.Host______.Host 255.255.0.0 Class B /17 /18 /19 /20 /21 /22 /23 /24 11111111.11111111.11111111.00000000 Network.Network.__Network.Host 255.255.255.0 Class C /25 /26 /27 /28 /29 /30 /31 /32 The First Octet is Reserved for the Network Only Class A, Class B, and Class C have subnets The host bits start on the 9th bit

How to Find CIDR Notation Find the intersection between the subnet and Class. The point of intersection is the CIDR Networks per Subnet 2 4 8 16 32 64 128 256 Dotted Decimal Notation 192 224 240 248 252 254 255 Hosts Per Subnet 1 Class A /9 /10 /11 /12 /13 /14 /15 /16 Class B /17 /18 /19 /20 /21 /22 /23 /24 Class C /25 /26 /27 /28 /29 /30 /31 /32 If the octet is all 1s this is a network bit You are given a subnet mask of 255.255.240.0, What is the CIDR Notation? 255.255.240.0 11111111.1111111.11110000.00000000 Network_.___A___.___B_____.___C____ Network_.Network.HostBits Class A is the 2nd Octet Class B is the 3rd Octet Class C is the 4th Octet The octet is not complete in the 3rd Octet, therefor this is a Class B address

How to Find Dotted Decimal /14 is in the 6th Row, this means 6 bits are turned on 11111100 Networks per Subnet 2 4 8 16 32 64 128 256 Dotted Decimal Notation 192 224 240 248 252 254 255 Hosts Per Subnet 1 Class A /9 /10 /11 /12 /13 /14 /15 /16 Class B /17 /18 /19 /20 /21 /22 /23 /24 Class C /25 /26 /27 /28 /29 /30 /31 /32 CIDR /14 is in the Class A Range If you are given a CIDR (Classless Inter-domain Routing) of /14, what is the subnet mask? Find /14 Find the intersection of Dotted Decimal and the CIDR # Network bits are always the 1st 8 bits 11111111.11111100.00000000.0000 255.252.0.0 2nd Octet is Class A, The /14 is class A, place intersection in Class A octet. If the CIDR was class B you would use the 2nd octet and 3rd for C