diff --git a/00. Jeremy's IT LAB CCNA course.md b/00. Jeremy's IT LAB CCNA course.md index 805afc6..587f4fd 100644 --- a/00. Jeremy's IT LAB CCNA course.md +++ b/00. Jeremy's IT LAB CCNA course.md @@ -24,3 +24,4 @@ tags: [[The Life of a Packet]] [[Subnetting (Part 1)]] [[Subnetting (Part 2)]] +[[Subnetting (Part 3 - VLSM)]] diff --git a/15. Subnetting (Part 3 - VLSM).md b/15. Subnetting (Part 3 - VLSM).md new file mode 100644 index 0000000..5a5ba51 --- /dev/null +++ b/15. Subnetting (Part 3 - VLSM).md @@ -0,0 +1,229 @@ +--- +id: 1777971486-WJIG +aliases: + - Subnetting (Part 3) +tags: [] +--- + +# Subnetting (Part 3 - VLSM) + + +class B Refference table + +| Prefix | Subnets | Hosts | +| ------ | ------- | ----- | +| /17 | 2 | 32766 | +| /18 | 4 | 16382 | +| /19 | 8 | 8190 | +| /20 | 16 | 4094 | +| /21 | 32 | 2046 | +| /22 | 64 | 1022 | +| /23 | 128 | 510 | +| /24 | 256 | 254 | + +--- + +class C Refference table + +| Prefix | Subnets | Hosts | +| ------ | ------- | ----- | +| /25 | 2 | 126 | +| /26 | 4 | 62 | +| /27 | 8 | 30 | +| /28 | 16 | 14 | +| /29 | 32 | 6 | +| /30 | 64 | 2 | +| /31 | | (0) | +| /32 | | (0)-2 | + +## QUIZ Question 1 + +You have been given the 172.30.0.0/16. your company requires +100 subnets with at least 500 hosts per subnet. What prefix +length should you use? + +I should use 172.168.0.0/23 +because it compatible with 100 subnet and 500 hosts + +subnet mask -> 255.255.254.0 + +## Quiz Question 2 + +What subnet does host 172.21.111.201/20 belong to ? + +10101100.00010101.*0110*1111.11001001 +172.21.111.201 +10101100.00010101.*0110*0000.00000000 +172.21.96.0 + +## Quiz question 3 + +What is the broadcast address of the network 192.168.91.78/26 + +11000000.10101000.10110011.*01*001110 +192.168.91.78 +11000000.10101000.10110011.*01*111111 +192.168.91.127 + +## Quiz question 4 + +You divide the 172.16.0.0/16 network into 4 subnets of equal size. +Identify the network and broadcast addresses of the second subnet + +Subnet 1 : +Network address +172.16.0.0/18 +10101100.00011010.*00*000000.00000000 +broadcast: +172.16.0.0/18 +10101100.00011010.*00*111111.00000000 +172.16.63.255/18 + +Subnet 2 : +Network address +172.16.64.0/18 +10101100.00011010.*01*000000.00000000 +broadcast: +172.16.65.0/18 +10101100.00011010.*01*111111.00000000 +172.16.127.255/18 + +Subnet 3 : +Network address +172.16.128.0/18 +10101100.00011010.*10*000000.00000000 +broadcast: +172.16.128.0/18 +10101100.00011010.*10*111111.00000000 +172.16.191.255/18 + +Subnet 4 : +Network address +172.16.192.0/18 +10101100.00011010.*11*000000.00000000 +broadcast: +172.16.192.0 +10101100.00011010.*11*111111.00000000 +172.16.255.255/18 + +## Quiz question 5 + +You divide the 172.30.0.0/16 network into subnets of 1000 hosts each. How many subnets +are you able to make + +I'm able to make 64 subnets + +## Subentting class A Networks + +The process of subnetting Class A, Class B and Class C networks is Exactly the same ! + +### Example 2 + +You hace been given the 10.0.0.0/8 network. You must create 2000 subnets which +will be distributed to various enterprises. +What prefix length must you use ? +How many host addresses usable addresses will be in each subnet? + +10.0.0.0 +00001010.00000000.0000000.0000000 +2, 4, 8, 16,32, 64,128,256, 512, 1024, 2048 +00001010.*00000000.000*00000.0000000 + + Answer: + 10.0.0.0/19 + 8192 - 2 = 8190 hosts + +### Example 2 + +PC1 has an IP address of 10.217.182.223/11. + +Identify the following for PC1's subnet: +1) Network address:10.192.0.0/11 +2) Broadcast address: 10.223.255.255 +3) First usable address: 10.192.0.1 +3) Last usable address:10.223.255.254 +3) Nuber of host (usable) address: 2,097,150 + +10.217.182.223 +00001010.*110*11001.10110110.11011111 + +## [[VLSM]] + +Variable-Length Subnet Masks + +- Until now, we have practiced subentting used FLSM (Fixed-Length Subnet Masks). +- This means that all of the subents use the same prefix length (ie. subnetting a class C +into 4 subenets using /26). +- VLSM (Variable-Length Subnet Masks) is the process of creating subnets of different sizes +to make your use of network addresses more eficient +- VLSM is more complicated than FLSM, but it's easy if you folow the steps correctly. + +### Exaple 1 + +We must divide 192.168.1.0/24 must divided between 5 subnets + + Tokyo Lan A = 110 Hosts --- Tokyo Lan B = 8 Hosts + | + Router + | + Router + | + Toronto Lan A = 29 Hosts --- Toronto Lan B = 45 Hosts + +#### VLSM Steps + +1) Assign the largest subnet at the start of the address space. +2) Assign the second- largest subnet after it. +3) Repeat the process until all subnets have been assigned + +we will do this in this order + +Tokyo LAN A -> Toronto LAN B -> Toronto LAN A -> Tokyo LAN B -> Point to point + +##### Tokyo LAN A + +Network address: 192.168.1.0/25 +Broadcast address: 192.168.1.127/25 +First usable address: 192.168.1.1/25 +Last usable address: 192.168.1.126/25 +Total Number of usable host address: 126 + +##### Toronto LAN B +if we add 1 to the Tokyo Broadcast address we get the next Network address + +Network address: 192.168.1.128/26 +Broadcast address: 192.168.1.191/26 +First usable address: 192.168.1.129/26 +Last usable address: 192.168.1.190/26 +Total Number of usable host address: 62 + +##### Toronto LAN B + +Network address: 192.168.1.192/27 +Broadcast address: 192.168.1.223/27 +First usable address:192.168.1.193/27 +Last usable address:192.168.1.222/27 +Total Number of usable host address:30 + +##### Tokyo LAN A + +Network address: 192.168.1.224/28 +Broadcast address: 192.168.1.239/28 +First usable address: 192.168.1.225 +Last usable address: 192.168.1.239 +Total Number of usable host address: 14 + +##### Point to Point + +Network address: 192.168.1.240/30 +Broadcast address: 192.168.1.243/30 +First usable address: 192.168.1.241/30 +Last usable address: 192.168.1.242/3 +Total Number of usable host address: 2 + +## Additional Practice + +- https://www.subnettingquestions.com +- https://www.subnetting.org +- https://www.subnettingpractice.com +