Lecture Notes For CCNA
Chapter 2- WAN Protocols
Differentiate between types
Frame Relay
High performance
Physical & Data link levels
Designed for ISDN
Error correction is for higher levels
Connection oriented PVC's
Frame Relay VCis 2x DTE with packet switched network inbetween, eah VC is identified by a Data Link Connection Identifier (DCLI)
ISDN - Integrated Services Digital Network
Physical, Data Link, Network, Transport Layers
set of comms protocols
HDLC - ISO standard
Data Link Layer, bit based for sync. serial links
High Level Data Link control
Cisco HDLC Won't communicate with any other vendor's
PPP
Async or Sync
Uses Link Control Protocol to build data link connections
Compression
CHAP / PAP authentication
Uses NCP to support IPX, IP, Appletalk, Decnet etc.
Frame Relay Terms
CO - Central Office
CPE - Customer Premise Equipment
DCE
DTE - typically routers
DLCI
demarc - Termination point of service provider's cable
PSE - packet switch exchange
PVC SVC
local loop - demarc to CO
Frame Relay config
encapsulation type on ser int.
int s0
encapsulation frame-relay [IETF]
default is cisco encaps. IETF used if other equip. is not Cisco
frame-relay interface-dlci ## - maps dlci to an interface
LMI - Local management Interface = How to communicate setting
cisco, ansi, q933a.
IOS 11.2 up LMI is auto detected
Subinterfaces
int s0.## [multipoint] / [point-to-point]
as many as needed, 0 to 32 bit value
p-2-p are for single virtual circuit, multi are when router is at centre of star
Mapping
int s0.16 point-to-point
encap frame-rela ietf
no inverse-arp
ip address 172.16.30.1 255.255.255.0
frame-relay map ip 172.16.30.17 20 cisco broadcast
frame-relay map ip 172.16.30.18 30 broadcast
frame-relay map ip 172.16.30.19 40 broadcast
Maps 3VC's with their DLCI's
Inverse ARP maps VC'sdynamically
first vc uses cisco encap. others default (ietf)
Monitoring Frame Relay
sh frame-relay
ip, lapf, lmi, map, pvc, route, svc, traffic
pvc - stats on all fr int's
shows dlci usage=local = dte
alternative dlci usage=switch
show running config shows dlci nums
frame lmi - stats and type of lmi used
traffic - general traffic stats
interface s0 - lmi info, dlci type not dlci no.
PPP
config t
int s0
encapsulation ppp
^z
showinterface
ISDN
Cisco treats ISDN as high speed
Protocols are E - exising tel network
I - concepts, terminology, services
Q - protocols switching / signalling
Functions, TE1 and TE2. TE1=BRI standard
TE2= pre standard and needs a TA
Reference points: r,S,T,U:
R - non-isdn & TA
S - user terminal & nt2
T - NT1 / NT2
U - NT1 & line termination unit
B & D channels : 64 /16kbps
BRI
Each BRI has an Service Provider Identifiers - SPID
isdn switch-type xxxxx depending upon provider
config t
isdn switch-type xxxxx
int bri0
encap ppp
isdn spid1 775456721
isdn spid2 775456722
Comments
Post a Comment