The additional subnets could be used from growth.
18 Chapter 2: Medium-Sized Switched Network Construction
Figure 2-3 IP Addressing per VLAN
Example: Network Design
A business with approximately 250 employees wants to migrate to the Cisco Enterprise
Architecture.
Table 2-1 shows the number of users in each department.
Six VLANs are required to accommodate one VLAN per user community. Following the
guidelines of the Cisco Enterprise Architecture, six IP subnets are required.
Table 2-1 Users per Department
Department Number of Users Location
IT 45 Building A
Human Resources 10 Building A
Sales 102 Building B
Marketing 29 Building B
Finance 18 Building C
Accounting 26 Building C
Core
10.1.1.0??“10.1.4.0/24
IT, Human Resources
10.2.1.0??“10.2.4.0/24
Sales, Marketing
10.3.1.0??“10.3.4.0/24
Finance, Accounting
Implementing VLANs and Trunks 19
The business has decided to use network 10.0.0.0 as its base address.
To accommodate future growth, there will be one block of IP addresses per building, as
follows:
?– Building A is allocated 10.1.0.0/16.
?– Building B is allocated 10.2.0.0/16.
?– Building C is allocated 10.3.0.0/16.
The sales department is the largest department, requiring a minimum of 102 addresses for
its users.
Pages:
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51