Tables Useful for IP Subnetting Activities

IPv4 Address Classes

Class First Octet Values Purpose
A 1 – 126 Unicast (large networks)
B 128 – 191 Unicast (medium-sized networks)
C 192 – 223 Unicast (small networks)
D 224 – 239 Multicast
E 240 – 255 Reserved (formerly experimental)
  • First Octet of 0 or 127: Reserved for Special Uses

 

Powers of 2

Power Decimal Power Decimal Power Decimal

20

 1 28 256 216 65,536
21 2 29 512 217 131,072
22 4 210 1024 218 262,144
23 8 211 2048 219 524,288
24 16 212 4096 220 1,048,576
25 32 213 8192 221 2,097,152
26 64 214 16,384 222 4,194,304
27 128 215 32,768 223 8,388,608

 

Private IPv4 Networks

Class of Networks Private IP Networks Number of Networks
A 10.0.0.0 1
B 172.16.0.0 through 171.31.0.0 16
C 192.168.0.0 through 192.168.255.0 256

 

The Nine DDN Octet Values

Decimal  Value Binary Number of Binary 1’s
0 00000000 0
128 10000000 1
192 11000000 2
224 11100000 3
240 11110000 4
248 11111000 5
252 11111100 6
254 11111110 7
255 11111111 8

 

Speed Goals and Learning Stages

Subnetting Processes Book Speed Goals Your Speed Goal Your Current Speed Your Current Stage
Find Classful Network Facts * 10
Convert Mask Formats * 10
Find Subnet Facts 30
Interpret Design w/ Mask 15
Choose One Mask 15
Find All Subnet IDs * 45
  • Excludes the time required to write all the answers on paper.

 

Binary-to-Decimal Conversion Chart: Decimal 0 – 127

Decimal Binary Decimal Binary Decimal Binary Decimal Binary
0 00000000 32 00100000 64 01000000 96 01100000
1 00000001 33 00100001 65 01000001 97 01100001
2 00000010 34 00100010 66 01000010 98 01100010
3 00000011 35 00100011 67 01000011 99 01100011
4 00000100 36 00100100 68 01000100 100 01100100
5 00000101 37 00100101 69 01000101 101 01100101
6 00000110 38 00100110 70 01000110 102 01100110
7 00000111 39 00100111 71 01000111 103 01100111
8 00001000 40 00101000 72 01001000 104 01101000
9 00001001 41 00101001 73 01001001 105 01101001
10 00001010 42 00101010 74 01001010 106 01101010
11 00001011 43 00101011 75 01001011 107 01101011
12 00001100 44 00101100 76 01001100 108 01101100
13 00001101 45 00101101 77 01001101 109 01101101
14 00001110 46 00101110 78 01001110 110 01101110
15 00001111 47 00101111 79 01001111 111 01101111
16 00010000 48 00110000 80 01010000 112 01110000
17 00010001 49 00110001 81 01010001 113 01110001
18 00010010 50 00110010 82 01010010 114 01110010
19 00010011 51 00110011 83 01010011 115 01110011
20 00010100 52 00110100 84 01010100 116 01110100
21 00010101 53 00110101 85 01010101 117 01110101
22 00010110 54 00110110 86 01010110 118 01110110
23 00010111 55 00110111 87 01010111 119 01110111
24 00011000 56 00111000 88 01011000 120 01111000
25 00011001 57 00111001 89 01011001 121 01111001
26 00011010 58 00111010 90 01011010 122 01111010
27 00011011 59 00111011 91 01011011 123 01111011
28 00011100 60 00111100 92 01011100 124 01111100
29 00011101 61 00111101 93 01011101 125 01111101
30 00011110 62 00111110 94 01011110 126 01111110
31 00011111 63 00111111 95 01011111 127 01111111

 

Binary-to-Decimal Conversion Chart: Decimal 128 – 255

Decimal Binary Decimal Binary Decimal Binary Decimal Binary
128 10000000 160 10100000 192 11000000 224 11100000
129 10000001 161 10100001 193 11000001 225 11100001
130 10000010 162 10100010 194 11000010 226 11100010
131 10000011 163 10100011 195 11000011 227 11100011
132 10000100 164 10100100 196 11000100 228 11100100
133 10000101 165 10100101 197 11000101 229 11100101
134 10000110 166 10100110 198 11000110 230 11100110
135 10000111 167 10100111 199 11000111 231 11100111
136 10001000 168 10101000 200 11001000 232 11101000
137 10001001 169 10101001 201 11001001 233 11101001
138 10001010 170 10101010 202 11001010 234 11101010
139 10001011 171 10101011 203 11001011 235 11101011
140 10001100 172 10101100 204 11001100 236 11101100
141 10001101 173 10101101 205 11001101 237 11101101
142 10001110 174 10101110 206 11001110 238 11101110
143 10001111 175 10101111 207 11001111 239 11101111
144 10010000 176 10110000 208 11010000 240 11110000
145 10010001 177 10110001 209 11010001 241 11110001
146 10010010 178 10110010 210 11010010 242 11110010
147 10010011 179 10110011 211 11010011 243 11110011
148 10010100 180 10110100 212 11010100 244 11110100
149 10010101 181 10110101 213 11010101 245 11110101
150 10010110 182 10110110 214 11010110 246 11110110
151 10010111 183 10110111 215 11010111 247 11110111
152 10011000 184 10111000 216 11011000 248 11111000
153 10011001 185 10111001 217 11011001 249 11111001
154 10011010 186 10111010 218 11011010 250 11111010
155 10011011 187 10111011 219 11011011 251 11111011
156 10011100 188 10111100 220 11011100 252 11111100
157 10011101 189 10111101 221 11011101 253 11111101
158 10011110 190 10111110 222 11011110 254 11111110
159 10011111 191 10111111 223 11011111 255 11111111

IP Subnetting Resources: Short URLs (wourl.io) Seen in the Course

http://wourl.io/subnet – A page about all IP Subnetting learning options from Wendell

http://wourl.io/subnet-exercises – A page listing all the exercises in the live course “IP Subnetting from Beginning to Mastery” at O’Reilly Learning

http://wourl.io/subnet-classnotes – This page of notes related to the live course “IP Subnetting from Beginning to Mastery” at O’Reilly Learning

http://wourl.io/subnet-video – A link to the recorded video product “IP Subnetting from Beginning to Mastery” at O’Reilly Learning

http://wourl.io/subnet-qa – A link to the question/answer product “IP Subnetting  Video and Practice Questions Kit” at O’Reilly Learning

http://wourl.io/subnet-book – A link to the eBook “CCNA 200-301 Official Cert Guide, Volume 1”, at O’Reilly Learning, which contains Chapters 11-14 about IP Subnetting

CCNA Practice Questions

The CCNA Official Cert Guides come with practice questions. You can use some of those practice questions at Safari (O’Reilly Online), and for others you must purchase the book(s). In particular:

  • The Safari offering includes all four CCNA Exam banks found in some of the books.
  • The Premium Edition eBook products from Cisco Press, namely the CCNA Vol 2 Premium Edition and the CCNA Library Premium Edition, include those same four CCNA exam banks.
  • The CCNA Vol 1 and CCNA Vol 2 books include other exam banks: one with all the questions from the chapter pre-quizzes, one with part review questions, and others that cover only the content in that book but not the other volume.
  • The print books include two exam banks, rather than four, for the general question types.

 

Links:

CCNA Questions from Premium Edition CCNA Library, on O’Reilly (Safari)

 

CCNA 200-301 Official Cert Guide, Volume 1, on CiscoPress.com

CCNA 200-301 Official Cert Guide, Volume 2, on CiscoPress.com

CCNA 200-301 Official Cert Guide Library (Contains Both Volumes) on CiscoPress.com

 

Premium Edition of CCNA 200-301 Official Cert Guide, Volume 1, on CiscoPress.com

Premium Edition of CCNA 200-301 Official Cert Guide, Volume 2, on CiscoPress.com

Premium Edition of CCNA 200-301 Official Cert Guide Library (Includes Both Vol 1 and 2), on CiscoPress.com

Wendell's Other Lab and Study Content

Wendell’s CCNA Blog: A large variety of content about CCNA Content from over the last eight years.

Config Labs for CCNA 200-301: Short configuration exercises for which you do not even need a simulator – just write your config on paper or type in an editor.

Packet Tracer Labs for the Books’ Examples: The blog has a series of posts about how to use Cisco Packet Tracer to re-create examples from the books. Each post matches a book chapter, with a goal of helping you decide which examples can be reasonably done in PT and which ones are probably too difficult to re-create in PT for various reasons.

Pearson Network Simulator: Think of it as like Packet Tracer, but with hundreds of built-in lab exercises, for usually around $100 US.