Default Configuration | How to configure default route in 3 routers

In this lab, I am gonna teach you How to configure the default route in 3 routers

Default Configuration VLSM

Given Network: 192.80.10.0

1) Required hosts on Router 1= 28

2) Required hosts on Router 2= 20

3) Required hosts on Router 3= 6

R1<= 28

28<= 2ⁿ – 2

28<= 2⁵ – 2

28<= 32 – 2

28<= 30

Total number of network bits = 32

32 – n = 32 – 5 = 27 (CIDR value of given network i.e. Router 1)

i.e. 192.80.10.0/27

N.S.M = 11111111. 11111111. 11111111.11100000

                        = 255.255.255.224

Block Size        = 256 – N.S.M

                        = 256 – 224 = 32

Note: Add this block size in given network so that we can get our new network for Router 2.

So the new network is 192.80.10.32/?

Now find FVH, LVH and Broadcast address

Given Network	192	80	10	0
First Valid Host-FVH	192	80	10	1
Last Valid Host-LVH	192	80	10	30
Broadcast	192	80	10	31
New Network	192	80	10	32

R2<= 20

20<= 2ⁿ – 2

20<= 2⁵ – 2

20<= 32 – 2

20<= 30

Total number of network bits = 32

32 – n = 32 – 5 = 27 (CIDR value of given network i.e. Router 2)

i.e. 192.80.10.32/27

N.S.M = 11111111. 11111111. 11111111.11100000

                        = 255.255.255.224

Block Size        = 256 – N.S.M

                        = 256 – 224 = 32

Note: Add this block size in given network so that we can get our new network for Router 3.

So the new network is 192.80.10.64/?

Now find FVH, LVH and Broadcast address

Given Network	192	80	10	32
First Valid Host-FVH	192	80	10	33
Last Valid Host-LVH	192	80	10	62
Broadcast	192	80	10	63
New Network	192	80	10	64

R3<= 6

6<= 2ⁿ – 2

6<= 2³ – 2

6<= 8 – 2

6<= 6

Total number of network bits = 32

32 – n = 32 – 3 = 29 (CIDR value of given network i.e. Router 3)

i.e. 192.80.10.64/29

N.S.M = 11111111. 11111111. 11111111.11111000

                        = 255.255.255.248

Block Size        = 256 – N.S.M

                        = 256 – 248 = 8

Note: Add this block size in given network so that we can get our new network for Router 1 and 2 (Virtual Network).

So the new network is 192.80.10.72/?

Now find FVH, LVH and Broadcast address

Given Network	192	80	10	64
First Valid Host-FVH	192	80	10	65
Last Valid Host-LVH	192	80	10	70
Broadcast	192	80	10	71
New Network	192	80	10	72

Router 1 & 2 <= 2 hosts (we required only two IP to connect 2 routers)

2 <= 2ⁿ – 2

2 <= 2² – 2

2 <= 4 – 2

2 <= 2

Total number of network bits = 32

32 – n = 32 – 2 = 30 (CIDR of Virtual network (R1&R2)

i.e. 198.10.10.72/30

N.S.M = 11111111.11111111.11111111.11111100

= 255.255.255.252

Block Size        = 256 – N.S.M

= 256 – 252 = 4

Note: Add this block size in given network so that we can get our new network for Router 2 and 3 (Virtual Network).

so the new network is 192.80.10.76/?

Now find FVH, LVH and Broadcast address

Given Network	192	80	10	72
First Valid Host-FVH	192	80	10	73
Last Valid Host-LVH	192	80	10	74
Broadcast	192	80	10	75
New Network	192	80	10	76

Router 2 & 3 <= 2 hosts (we required only two IP to connect 2 routers)

2 <= 2ⁿ – 2

2 <= 2² – 2

2 <= 4 – 2

2 <= 2

Total number of network bits = 32

32 – n = 32 – 2 = 30 (CIDR of Virtual network (R2&R3)

i.e. 198.10.10.76/30

N.S.M = 11111111.11111111.11111111.11111100

= 255.255.255.252

Block Size        = 256 – N.S.M

= 256 – 252 = 4

Note: Add this block size in given network so that we can get our new network for Router 4. This network can be used in future.

so the new network is 192.80.10.80/?

Now find FVH, LVH and Broadcast address

Given Network	192	80	10	76
First Valid Host-FVH	192	80	10	77
Last Valid Host-LVH	192	80	10	78
Broadcast	192	80	10	79
New Network	192	80	10	80

Class A, Class B, Class C, Master in Networking, all e-books – Combo offer- 50% off.

Basic Configuration on Router 1

Router>enable Router#configure terminal Router(config)#hostname R1 R1(config)#interface fastEthernet 0/0 R1(config-if)#ip address 192.80.10.1 255.255.255.224 R1(config-if)#no shutdown R1(config-if)#exit   R1(config)#interface serial 0/0/0 R1(config-if)#ip address 192.80.10.73 255.255.255.252 R1(config-if)#clock rate 64000 R1(config-if)#no shutdown R1#write

Basic Configuration on Router 2

Router>enable Router#configure terminal Router(config)#hostname R2 R2(config)#interface fastEthernet 0/0 R2(config-if)#ip address 192.80.10.33 255.255.255.224 R2(config-if)#no shutdown R2(config-if)#exit   R2(config)#interface serial 0/1/0 R2(config-if)#ip address 192.80.10.74 255.255.255.252 R2(config-if)#no shutdown R2(config-if)#exit   R2(config)#interface serial 0/0/0 R2(config-if)#ip address 192.80.10.77 255.255.255.252 R2(config-if)#clock rate 64000 R2(config-if)#no shutdown R2(config-if)#exit R2(config)#exit R2#write

Basic Configuration on Router 3

Router>enable Router#configure terminal Router(config)#hostname R3 R3(config)#interface fastEthernet 0/0 R3(config-if)#ip address 192.80.10.65 255.255.255.248 R3(config-if)#no shutdown R3(config-if)#exit   R3(config)#interface serial 0/1/0 R3(config-if)#ip address 192.80.10.78 255.255.255.252 R3(config-if)#no shutdown R3(config-if)#exit R3(config)#exit R3#write

Default Configuration on Router 1

R1>enable R1#configure terminal R1(config)#ip route 0.0.0.0                0.0.0.0                         192.80.10.74 R1(config)#exit R1#write

Default Configuration on Router 2

R2>enable R2#configure terminal R2(config)#ip route 192.80.10.0        255.255.255.224         192.80.10.73 R2(config)#ip route 192.80.10.64      255.255.255.248         192.80.10.78 R2(config)# R2(config)#ip route 192.80.10.72      255.255.255.252         192.80.10.73 R2(config)#ip route 192.80.10.76      255.255.255.252         192.80.10.78 R2(config)#exit R2#write

Default Configuration on Router 3

R3>enable R3#configure terminal R3(config)#ip route 0.0.0.0                0.0.0.0                         192.80.10.77 R3(config)#exit R3#write

Verification on Router 1

R1#show ip route      192.80.10.0/24 is variably subnetted, 2 subnets, 2 masks C       192.80.10.0/27 is directly connected, FastEthernet0/0 C       192.80.10.72/30 is directly connected, Serial0/0/0 S*   0.0.0.0/0 [1/0] via 192.80.10.74

Verification on Router 2

R2#show ip route      192.80.10.0/24 is variably subnetted, 5 subnets, 3 masks S       192.80.10.0/27 [1/0] via 192.80.10.73 C       192.80.10.32/27 is directly connected, FastEthernet0/0 S       192.80.10.64/29 [1/0] via 192.80.10.78 C       192.80.10.72/30 is directly connected, Serial0/1/0 C       192.80.10.76/30 is directly connected, Serial0/0/0

Verification on Router 3

R3#show ip route      192.80.10.0/24 is variably subnetted, 2 subnets, 2 masks C       192.80.10.64/29 is directly connected, FastEthernet0/0 C       192.80.10.76/30 is directly connected, Serial0/1/0 S*   0.0.0.0/0 [1/0] via 192.80.10.77

If you like our LABs, you can support us by donating just $1. It will really encourage us. EIHeducation