Exercise:
- Exercise: Create a private network with 3 subnets
- Each subnet requires 25000 devices to be connected
- Solution
2^n ~= 75000
host id = 17 bits
private cidr ranges
192.168.0.0/16 => max host id = 16 bits
172.16.0.0/12 => max host id = 20 bits
10.0.0.0/8 => max host ids = 24 bits
- We can’t use 192.168.0.0/16 as maxium host bits are 16 but we need 17
- So lets choose 172.16.0.0/12
network cidr: 172.16.0.0/15
network ip: 10101100.00010000.00000000.00000000
subnetmask: 11111111.11111110.00000000.00000000
network rg: 10101100.0001000x.xxxxxxxx.xxxxxxxx
each subnet = 25000 2^n ~=25000 n (host id)= 15
subnet network range: network rg: 10101100.0001000x.xyyyyyyy.yyyyyyyy
possibilities
subnet 1: 10101100.00010000.0yyyyyyy.yyyyyyyy => 172.16.0.0/17
subnet 2: 10101100.00010000.1yyyyyyy.yyyyyyyy => 172.16.128.0/17
subnet 3: 10101100.00010001.0yyyyyyy.yyyyyyyy => 172.17.0.0/17
Network cidr: 172.16.0.0/15
subnet1 : 172.16.0.0/17
subnet2: 172.16.128.0/17
subnet3: 172.17.0.0/17
- Exercise: Create a cidr range for a network with 5 subnets with 50 devices each.
2^n ~ = 250
n = 9
10.10.0.0/23
IP: 00001010.00001010.00000000.00000000
SM: 11111111.11111111.11111110.00000000
2^n ~= 50
n = 6
IP: 00001010.00001010.0000000x.xxxxxxxx
IP: 00001010.00001010.0000000x.xxyyyyyy
possibilities
s1: 00001010.00001010.00000000.00yyyyyy => 10.10.0.0/26
s2: 00001010.00001010.00000000.01yyyyyy => 10.10.0.64/26
s3: 00001010.00001010.00000000.10yyyyyy => 10.10.0.128/26
s4: 00001010.00001010.00000000.11yyyyyy => 10.10.0.192/26
s5: 00001010.00001010.00000001.00yyyyyy => 10.10.1.0/26
Networking Basics
- Device with in a network can communicate directly with any other device in the same network.
- Devices in the same network have same network id
- Two device in the different network cannot communicate directly
- In networking we have a device called as router which can forward packets from one network to other
- Routers will forward the packets from one network to other depending on the routes configured
- see the following image from tracing route to reach public servers
- Basic image
Lets understand on Networking in AWS
- To create networks in AWS, we need to understand
- Regions: Geographical location where AWS has datacenters
- Availability zones (AZ): These are the actual sites within a Region where AWS hosts the infrastructure. Two AZ’s in a region will be typically 30 – 60 kms far away from each other. There will be a dedicate optical fiber network b/w AZ’s
- To create a network in AWS, we use a service called as VPC (Virtual Private Cloud)
- Network is created at a region level
- Subnets are created at AZ level
- Now lets try to create our first vpc
- Now lets add two subnets
Note: Free tier aws account creation Refer Here
