Point-to-Point Frame Relay with Cisco router as Frame Relay Switch

In this tutorial, I will show you, how to use a Cisco router as a frame relay switch. It can be usefull if you study for your CCNA or CCNP exam and you need a frame relay switch, although you can use GNS3's Frame Relay switch, it can be a little buggy.

The topology used:

FRSW is the Frame Relay switch, which is connected to London, Budapest and Baltimore.

PVCs:
P2P 102 London Baltimore
P2P 201 Baltimore London
P2P 103 London Budapest
P2P 301 Budapest London

Step1

In this step we will enable Frame Relay switching on router FRSW, then we create the appropriate DLCIs.

FRSW(config)#frame-relay switching

On the serial interface 1/0, 1/1, 1/3 configure frame-relay:

FRSW(config)#int serial 1/0
FRSW(config-if)#encapsulation frame-relay
FRSW(config-if)#frame-relay lmi-type cisco
FRSW(config-if)#clock rate 64000
FRSW(config-if)#frame-relay intf-type dce
FRSW(config-if)#no shutdown

FRSW(config)#int serial 1/1
FRSW(config-if)#encapsulation frame-relay
FRSW(config-if)#frame-relay lmi-type cisco
FRSW(config-if)#clock rate 64000
FRSW(config-if)#frame-relay intf-type dce
FRSW(config-if)#no shutdown

FRSW(config)#int serial 1/3
FRSW(config-if)#encapsulation frame-relay
FRSW(config-if)#frame-relay lmi-type cisco
FRSW(config-if)#clock rate 64000
FRSW(config-if)#frame-relay intf-type dce
FRSW(config-if)#no shutdown

Then create the routes on each interfaces, the command is:

frame-relay route INDLCI interface OUTINTERFACE OUTDLCI

so..

FRSW(config)#int serial 1/0
FRSW(config-if)#frame-relay route 103 interface s1/1 301
FRSW(config-if)#frame-relay route 102 interface s1/3 201

FRSW(config)#int serial 1/1
FRSW(config-if)#frame-relay route 301 interface serial 1/0 103
FRSW(config)#int ser1/3
FRSW(config-if)#frame-relay route 201 interface serial 1/0 102

Step2: Configure Nodes

London:

London(config)#int ser1/0
London(config-if)#encapsulation frame-relay
London(config-if)#no sh

London(config)#int ser1/0.103 point-to-point
London(config-subif)#ip addr 192.168.3.1 255.255.255.0
London(config-subif)#frame-relay interface-dlci 103
London(config-subif)#no sh

London(config)#int ser1/0.102 point-to-point
London(config-subif)#ip addr 192.168.1.1 255.255.255.0
London(config-subif)#frame-relay interface-dlci 102
London(config-subif)#no sh

Budapest:

Budapest(config)#int ser1/0
Budapest(config-if)#encapsulation frame-relay
Budapest(config-if)#no sh

Budapest(config)#int ser1/0.301 point-to-point
Budapest(config-subif)#ip addr 192.168.3.2 255.255.255.0
Budapest(config-subif)#frame-relay interface-dlci 301
Budapest(config-subif)#no sh

Baltimore

Baltimore(config)#int ser1/0
Baltimore(config-if)#encapsulation frame-relay
Baltimore(config-if)#no sh

Baltimore(config)#int ser1/0.201 point-to-point 
Baltimore(config-subif)#ip addr 192.168.1.2 255.255.255.0
Baltimore(config-subif)#frame-relay interface-dlci 201
Baltimore(config-subif)#no sh

Step3: Test

Ping London from Baltimore:

Baltimore#ping 192.168.1.1
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 192.168.1.1, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 4/6/8 ms

Ping London from Budapest:

Budapest#ping 192.168.3.1
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 192.168.3.1, timeout is 2 seconds:
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 4/4/4 ms

Step4: Set up routing

Budapest:

Budapest(config)#ip route 0.0.0.0 0.0.0.0 192.168.3.1

Baltimore:

Baltimore(config)#ip route 0.0.0.0 0.0.0.0 192.168.2.1