CCNA learning WAN

WAN

WAN Protocol

SDLC:             Synchronous Data Link Control

HDLC:            High-Level Data Link Control

PPP:               Point to Point Protocol

X.25:               Packet Level Protocol

Frame Relay:  Simplified version of HDLC framing

ISDN:              Integrated Services Digital Network

Private Network

1. Long time transfer

2. Short distance

Package Exchange: share physical

line --> X.25 / Frame Relay

1. long time transfer

2. long distance

Frame Relay

1. Speed: 56/64 Kbps, 256Kbps, 2Mbps

2. Permanent exchange, no dial

3. Data-link layer

Electrical Exchange --> ISDN, ADSL, DIAL-IN

1. backup connection

2. short time transfer

3. small data transfer

ISDN

D: Transfer Signal 64Kbps

B: User data 64Kbps

BRI (Basic Rate Interface) = 2B + D = 144Kbps

PRI (Primary Rate Interface)= 30B +D = 2Mbps

xDSL: ADSL, VDSL, SDSL...

Use higher frequency range(4400hz - 1Mhz) in telephone line to do data transfer

VPN (virtual private network)

Use software technology make internet(Frame Relay / ADSL) as private network for customers --> Add security

Solution: Make Channel on layer 2 or layer 3

Layer 3 Protocol: IPSec (TCP Port), GRE

Layer 2 Protocol: L2TP (UDP Port), L2F, PPTP (UDP Port)

HDLC (High-Level Data Link Control)

Cisco device not compatible with other brand devices

Set: (config-if)#encapsulation hdlc

Cisco default serial port protocol is hdlc

PPP (Point to Point Protocol)

PPP Protocol: NCP(network control protocol) / LCP(Link control protocol)

NCP: communicate with higher layer

LCP: establish and control connection

PPP dialog setup:

1. Data link establish

2. Verification(optional)

3. Network layer connection

PPP Verification Protocol: PAP / CHAP

PAP(Password Authentication Protocol) process: 2-way handshake

1. Transfer plain text password

2. Verify both sides

CHAP(Challenge Handshake Authentication Protocol) process:  3-way handshake

Detail Process:

Step 1

Step 2

Step 3

Step 4

Step 5

Step 6

CHAP config

(config)#hostname <hostname>

(config)#username <hostname> password <password>

(config-if)#int serial 0....

(config-if)#encapsulation ppp

(config-if)#ppp authentication chap

Example

Check: #show interface s0

Frame Relay

Frame Relay Network Topo Structure:

1. Full Mesh

2. Partial Mesh

3. Start(Hub and Spoke)

DTE (Data Terminal Equipment): User end device

DCE (Data Communication Equipment): Service Provide end device

VC (Virtual Connection): Many logical data communication in one physical data link, which identified by connection identification

LMI(Local Management Interface): Manage the DLCI status

DLCI (Data Link Connection Identifier): Identify the VC between DTE and FR

Frame Relay Map

Source DLCI <-> Dest. IP

Reason: There is only one physical port of router used for FR. The destination only can be identified by DLCI.

LMI Standard:

1. Cisco

2. ANSI T1.617

3. ITU-T Q.933

FR Automatic Establish Map Process (Reserve ARP and LMI) (status will be dynamic) :

FR config

Manually Config Frame Relay Map (status will be static)

FR config Example

Config for 2503

Config for 2501

FR config verification

FR points over two which using parallel division trigger router map not

comprehensive.

Solution:

1. Close parallel division, need to confirm there is no loop potential.

2. Make logical sub port

Sub Port Solution

1. Point to Point sub port  --> hub and stock mesh

every sub port need sub net

2. Multi Point sub port --> full mesh / partial mesh

all sub ports need only one sub net

Point to point sub port config

Multi point sub port config

ISDN Intergrated Services Digital Network

Advantage:

1. Establish quickly

2. Rent cost low

3. Speed faster then simulate signal

ISDN Service Mode:

1. BRI Basic Rate Interface: 2*B+D

2. PRI Primary Rate Interface: 30*B + D

B: Data Transfer HDLC, PPP

D: Signal Transfer LAPD

ISDN Work Process

ISDN Port Change Process

ISDN DDR Demand Dial Router

1. Timely Connection

2. Small amount data transfer

DDR Work Process

1. Establish the target path

2. DDR trigger condition

3. Check dial information

4. Data transfer

5. End dialog

DDR config

1. config static router

2. config trigger condition

3. config dial information

Config static router

Config trigger condition

Config dial information

Config Summary

Verification

Debug