2. SUBNETTING CALCULATION

 

 Subnetting Calculation    

In this section, you are expecting to show the calculation on how to identify the IP address that was assigned for the Ulearn System Server based on the information given in the project scenario. Explain the concept and show the calculation to identify the IP address.

Based on 🔗 project scenario given, we will use subnet Class B. 

Figure 1: Class B subnet list 

Default Class B mask  = 255.255.0.0 (16 bits) 

There will be 9 subnet = 8 faculties + 1 IT Center 

IP Address = 172.16.0000 0000.0000 0000/16

As shown in Figure 1 above, the nearest network bits that we can use /20 because the number of subnets is 16 or we can follow step below. 

Subnetting step:

1) Calculate required host bit to be borrowed by using this formula 

 2ⁿ >=  no. of subnets needed

for this scenario, the calculation will be: 

2ⁿ ≥ 9 

2⁴ ≥ 9 

no. of host bits must be borrowed, n = 4 

2) New subnet mask 

From the calculation of borrowed host bits above, a new subnet mask is created 

Subnet mask prefix = 16 bits (before) + 4 bits (borrowed) =20

The new subnet mask prefix is = /20

From

/16= 255.255.0.0  or 1111 1111. 1111 1111. 0000 0000. 0000 0000

to 

/20= 255.255.240.0 or 1111 1111. 1111 1111. 1111 0000. 0000 0000

3) Assign each address on every subnet 

Based on new subnet mask that we created earlier, we can assign each subnet or faculties their address.

IP Address = 172.16.0000 0000.0000 0000

Figures 2: IP address range on each subnet  

 Table below shows network address, host range address and broadcast address on each subnet. 

Table 1: Subnetting address 

The IT center is assigned as the 9th subnet which is 172.16.128.0/20 . 

According to the 🔗 question, the Ulearn System Server is assigned at the 5th available address. So, we can assign the address of the Ulearn System  server as 172.16.128.6/20 

The address 172.16.128.1 will  ❌ not be count as it will be used for the router address.

📌 Address for the Ulearn System Server = 172.16.128.6/20