VLAN'S ROUTER SIDE

Sub interface configuration as Native VLAN

R1(config)int fa0/0.99
R1(config-subif) encap dot1q 99 native
R1(config-subif) ip address {IPADDRESS} {MASK}


VLAN Sub interface configuration

R1(config)int fa0/0.99
R1(config-subif) encap dot1q 99
R1(config-subif) ip address {IPADDRESS} {MASK}