Below a configuration with the following devices:

• Firewall
• Cisco 2811 router
• Cisco 2960 switch
• 3 laptops

After setting up this configuration, all laptops can ping each other.

Partial config 2811b:

!
interface FastEthernet0/0
description Connection to firewall
ip address 172.16.0.3 255.255.255.0
duplex auto
speed auto
!
interface FastEthernet0/1
ip address 192.168.10.1 255.255.255.240
duplex auto
speed auto
!
interface FastEthernet0/1.2
encapsulation dot1Q 2
ip address 192.168.1.65 255.255.255.192
!
interface FastEthernet0/1.10
encapsulation dot1Q 10
ip address 192.168.1.129 255.255.255.224
!

Partial config 2960b:

!
interface FastEthernet0/1
description Uplink Cisco 2811b
switchport mode trunk
!
interface FastEthernet0/2
switchport access vlan 2
!
interface FastEthernet0/3
switchport access vlan 2
!
interface FastEthernet0/4
switchport access vlan 10
!

For completion, the routing table on the router 2811b:

2811b#show ip route
Codes: C – connected, S – static, 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
i – IS-IS, su – IS-IS summary, 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 172.16.0.1 to network 0.0.0.0

192.168.10.0/28 is subnetted, 1 subnets
C 192.168.10.0 is directly connected, FastEthernet0/1
172.16.0.0/24 is subnetted, 1 subnets
C 172.16.0.0 is directly connected, FastEthernet0/0
192.168.1.0/24 is variably subnetted, 2 subnets, 2 masks
C 192.168.1.64/26 is directly connected, FastEthernet0/1.2
C 192.168.1.128/27 is directly connected, FastEthernet0/1.10
S* 0.0.0.0/0 [1/0] via 172.16.0.1