8.5.2002 Teemu.Korpela@mulkkeri.net
Subnetworks exercises 2:
Basics:
Deal addresses for subnet shown in the picture so that every interface of a router has its own address of that subnet and so that in the cloud all hosts have enough addresses. Remember to reserve addresses also for network and broadcast addresses. In one network there can be only one subnet. Use variable length subnet masks (VLSM) for optimal subnets. Reserve for growth need not take into account.
Exercise 1:
Usable address space:
192.168.0.0/22
Amount of hosts in the networks:
A: 15
B: 51
C: 31
D: 370
E: 1
F: 16
G: 24
H: 4
I: 24
J: No hosts, only the interfaces of the routers.
D: 192.168.0.0/23 --- 192.168.1.255/23
B: 192.168.2.0/26 --- 192.168.2.63/26
C: 192.168.2.64/26 --- 192.168.2.127/26
G: 192.168.2.128/27 --- 192.168.2.159/27
I: 192.168.2.160/27 --- 192.168.2.191/27
A: 192.168.2.192/27 --- 192.168.2.223/27
H: 192.168.2.224/28 --- 192.168.2.239/28
E: 192.168.2.240/29 --- 192.168.2.247/29
J: 192.168.2.248/30 --- 192.168.2.251/30
How many addresses are out of use?
255-251 = 4, from 192.168.3.0 to 192.168.3.255, there are 256, so totally, 260 are out of use.
Exercise 2:
Usable address spaces:
192.168.0.0/25
192.168.128.0/26
192.168.128.192/26
Amount of hosts in the networks:
A: 2
B: 4
C: 6
D: 25
E: 3
F: 15
G: 10
H: 1
I: 45
J No hosts, only the interfaces of the routers.
I: 192.168.0.0/26 --- 192.168.0.63/26
D: 192.168.0.64/27 --- 192.168.0.95/27
F: 192.168.0.96/27 --- 192.168.0.127/27
G: 192.168.128.0/28 --- 192.168.128.15/28
C: 192.168.128.16/28 --- 192.168.128.31/28
B: 192.168.128.32/29 --- 192.168.128.39/28
E: 192.168.128.40/29 --- 192.168.128.47/29
H: 192.168.128.48/29 --- 192.168.128.55/29
A: 192.168.128.56/29 --- 192.168.128.63/29
J: 192.168.128.192/30 --- 192.168.128.195/30
How many addresses are out of use?
255-195 = 60 addresses are out of use.