Router

Nerd Cafe

Function:

Layer 3 device that makes forwarding decisions based on logical network addresses (e.g., IP addresses).

Key Features:

• Segments networks by not forwarding broadcast packets by default, creating separate broadcast domains per port.

• Each port also creates a separate collision domain, enhancing network efficiency.

• Supports advanced features like QoS for traffic prioritization.

Topology

Summary Table of IP Assignments

Device	Interface	IP Address	Subnet
Router	fa0/0	192.168.1.1	192.168.1.0/24
Router	fa0/1	192.168.2.1	192.168.2.0/24
PC0	NIC	192.168.1.10	192.168.1.0/24
PC1	NIC	192.168.1.11	192.168.1.0/24
PC2	NIC	192.168.2.10	192.168.2.0/24
PC3	NIC	192.168.2.11	192.168.2.0/24

Configure the Router Interfaces

Router>enable 
Router#configure terminal 
Router(config)#interface fastEthernet 0/0
Router(config-if)#ip address 192.168.1.1 255.255.255.0
Router(config-if)#no shutdown 
Router(config-if)#exit
Router(config)#interface fastEthernet 0/1
Router(config-if)#ip address 192.168.2.1 255.255.255.0
Router(config-if)#no shutdown 
Router(config-if)#^Z
Router#show ip route 
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP
       D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
       N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
       E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
       i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, ia - IS-IS inter area
       * - candidate default, U - per-user static route, o - ODR
       P - periodic downloaded static route

Gateway of last resort is not set

C    192.168.1.0/24 is directly connected, FastEthernet0/0
C    192.168.2.0/24 is directly connected, FastEthernet0/1
Router#

Test Connectivity

On a PC, open Command Prompt → ping the other subnet:

PC>ping 192.168.2.10

Pinging 192.168.2.10 with 32 bytes of data:

Reply from 192.168.2.10: bytes=32 time=0ms TTL=127
Reply from 192.168.2.10: bytes=32 time=0ms TTL=127
Reply from 192.168.2.10: bytes=32 time=0ms TTL=127
Reply from 192.168.2.10: bytes=32 time=0ms TTL=127

Ping statistics for 192.168.2.10:
    Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
    Minimum = 0ms, Maximum = 0ms, Average = 0ms

PC>

Congratulations!

You have built a two-subnet, router-on-a-stick-style topology in Packet Tracer, perfect for practicing basic routing between LANs.