configuring WAN point to point links with HDLC, PPP and frame-relay protocols.

1. RAFAT KHANDAKER
PACKET TRACER
WAN LINKS POINT TO POINT
05/09/16
.
ABSTRACT
Configuring point to point WAN serial interface with multiple encapsulation types such
as: HDLC, PPP, Frame relay. Testing configuration settings in packet tracer to study different
WAN link settings through DCE/DTE serial interfaces.
INTRODUCTION
Serial interfaces on WAN links, going to the ISP, are encapsulated with certain protocols
to govern point to point connections. HDLC is a cisco proprietary protocol used for cisco routers
to communicate point to point links, It use a checksum error but the protocal is not widely used.
PPP protocol is more universally used because it supports more router vendors, other than cisco.
PPP also allows CHAP or PAP authentication between PPP devices. Frame Relay is more
commonly used due to it's hi-speed availability and also more cheap to implementation.

2. HDLC encapsulation (Low left router to core)
(LOWER LEFT ROUTER)

3. FINAL SHOW RUN

4. CORE ROUTER ( Simulating error with point to point mismatch )

5. NOTICE IT SAYS: " SERIAL INTERFACE IS UP, HOWEVER, LINE PROTOCOL IS
DOWN."
THIS IS THE ERROR WE EXPECT TO SEE WHEN PROTOCOL IS MISMATCHED.
INTERFACE WHEN MATCHED :

6. WE CAN SEE IN THE ORANGE ( HDLC Point to Point )

7. PING IS SUCCESSFUL !!
PPP WAN TO WAN LINK
For PPP we have the option to encrypt our chanel with pap or chap authentication. PAP
authentication is sent through the wan link in clear text, so the password to authenticate can
easily be sniffed through traffic. CHAP authentication is somewhat better because the password
is, at the minimum, hashed in an algorithm. Some other authentication that may be useful, MS-
Chap V2, V3 which are more secure. PPP also allows us to compress or stack the data that we
can send through the link.
Bottom, Right Router config.

8. Core Router config

9. PING IS SUCCESSFUL !!
show debug int s3/0 from core router :
We can see that line protocol is up and LCP is open in ppp encapsulation. LCP is link control
protocol, this needs to be in the open state before ppp can communicate through wan links.

10. FRAME RELAY POINT TO POINT NETWORK
FRAME RELAY is a point to point local link usually between the ISP and the local
management router. Frame Relay is cost effective and reliable. Frame Relay service provider
guarantees a fixed bandwitdth. CIR, commited information rate is the commited bandwidth that
the frame relay provider will give us. Frame Relay use packet switching protocol, where packets
are transmitted and re-assembled in a frame-relay network.
Frame Relay cloud, DCE routers in a frame switched network.
Terms:
PVC : permanent virtual circuit ( popular ) - available all the time. PVC use full mesh or partial
mesh

11. Full Mesh
Partial Mesh -Hub and spoke.
SVC: switched virtual circuit - available under certain conditions.
PVC use... LMI, Local Management Interface, which are Hello and response packets to keep
Frame Relay PVC links up.
DLCI

12. DLCI in a Frame Relay Network, Data-Link Connection Identifier. DLCI's are frame-relay layer
2 address, however, it can be re-used from router to router.
- Inverse ARP --> usually enabled by default on a cisco interface running Frame-Relay.
( encapsulation frame-relay command and then open the interface. You're running
inverse ARP.
after configuration : enable mode: show frame map --> command to troubleshoot frame-relay
CORE WAN ROUTER ( DCE )
TOP ROUTER

13. ping is unsuccessful
MANUALLY CONFIGURING DLCI , INVERSE ARP on Frame Relay network
TOP ROUTER

14. CORE ROUTER
Show frame map - command from Core Router
status is active and statically assigned... simulation purpose.
Ping is still uncucessful.....
Continuing troubleshooting....
I'm going to configure Frame Relay in a separate network for simulation, based on resource
material from http://websistent.com/how-to-configure-frame-relay-in-cisco-packet-tracer/
From this document, I realized that static routing needs to be configured in order for Frame-
Relay to function.

15. Fixing original packet tracer diagram
Core Router
Top Router
Ping is still unsuccessful from previous problem.
I am going to configure Frame Relay wih a frame relay cloud network. I noticed in this example
that subinterfaces are configured with point to point on the same DLCI address. I hope this
configuration helps to identify Frame-Relay under more reliable circumstances.
ROUTER 0

16. ROUTER 2
ROUTER 1

17. ALL SETTINGS ARE CORRECTLY CONFIGURED EXCEPT FOR THE CLOUD AT THIS
POINT
* packet tracer will not let me configure the cloud * error.* ... the configuration should be right at
this point, a frame relay table needs to be configured.
RESULTS
In this lab I have been able to configure WAN point to point link connections. I was able to
successfully implement PPP and HDLC networks. Frame-Relay networks was a prize worthy
experience, I learned a lot about this network. I will attempt to do more research to fix Frame
relay, from what I know so far, Frame-Relay at this network was configured correctly.
RESOURCES:
https://www.youtube.com/watch?v=8JlGioR6JlI
http://www.cisco.com/c/en/us/support/docs/wan/point-to-point-protocol-ppp/25647-
understanding-ppp-chap.html
http://www.cisco.com/c/en/us/td/docs/ios/12_2/debug/command/reference/122debug/dbfintro.ht
ml