building cisco remote access networks phần 6 ppsx

Configuring and Backing Up Permanent Connections • Chapter 7 277
Figure 7.15 Continued.
!
interface Serial2.3 point-to-point
description frame relay to router 1
ip unnumbered Ethernet0
no ip route-cache
frame-relay interface-dlci 101
no shutdown
!
interface Serial3
no ip address
no ip route-cache
no ip mroute-cache
shutdown
!
interface BRI0
no ip address
no ip route-cache
no ip mroute-cache
shutdown
!
router eigrp 100
network 10.0.0.0
!
ip classless
!
!
banner motd ^C
Establish a Frame Relay PVCs on three routers and control
traffic flow. - Router_2

^C
!
line con 0
exec-timeout 0 0
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278 Chapter 7 • Configuring and Backing Up Permanent Connections
Figure 7.15 Continued.
password xxxx
login
line aux 0
password xxxx
login
transport input all
line vty 0 4
password xxxx
login
!
end
Figure 7.16 Router3 configuration.
Router3
!
version 11.3
service timestamps debug uptime
service timestamps log uptime
no service password-encryption
service udp-small-servers
service tcp-small-servers
!

hostname Router_3
!
enable password xxxx
!
!
interface Ethernet0
ip address 10.3.3.3 255.255.255.0
no ip route-cache
no ip mroute-cache
!
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Configuring and Backing Up Permanent Connections • Chapter 7 279
Figure 7.16 Continued.
interface Serial0
no ip address
no ip route-cache
no ip mroute-cache
shutdown
!
interface Serial2.4 point-to-point
description frame relay to router a
ip unnumbered Ethernet0
no ip route-cache
frame-relay interface-dlci 103
no shutdown
!
router eigrp 100
network 10.0.0.0

!
ip classless
!
!
banner motd ^C
Establish a Frame Relay PVCs on three routers and control
traffic flow. - Router_3
^C
!
line con 0
exec-timeout 0 0
password xxxx
login
line aux 0
password xxxx
login
transport input all
line vty 0 4
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280 Chapter 7 • Configuring and Backing Up Permanent Connections
Figure 7.16 Continued.
password xxxx
login
!
end
Verifying Traffic Shaping
The functioning of traffic shaping configurations can be monitored through
various show and debug commands. These are:

■
show frame-relay pvc
■
show frame-relay lmi
■
show interface
■
show ip route
■
show traffic shap
■
show frame-relay map
■
debug frame-relay lmi
Let’s look at the related output that each of these commands produces.
Router1#show frame-relay pvc
PVC Statistics for interface Serial2 (Frame Relay DTE)
DLCI = 100, DLCI USAGE = LOCAL, PVC STATUS = ACTIVE, INTERFACE =
Serial2.1
input pkts 21 output pkts 24 in bytes 2014
out bytes 2066 dropped pkts 0 in FECN pkts 0
in BECN pkts 0 out FECN pkts 0 out BECN pkts 0
Æ shows BECN packets count
in DE pkts 0 out DE pkts 0
out bcast pkts 22 out bcast bytes 1838
pvc create time 00:12:17, last time pvc status changed 00:01:19
DLCI = 102, DLCI USAGE = LOCAL, PVC STATUS = ACTIVE, INTERFACE =
Serial2.2
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input pkts 11 output pkts 15 in bytes 804
out bytes 1750 dropped pkts 0 in FECN pkts 0
in BECN pkts 0 out FECN pkts 0 out BECN pkts 0
in DE pkts 0 out DE pkts 0
out bcast pkts 12 out bcast bytes 1198
pvc create time 00:11:03, last time pvc status changed 00:00:40
Router1#show frame-relay traffic
Frame Relay statistics:
ARP requests sent 0, ARP replies sent 0
ARP request recvd 0, ARP replies recvd
Router1#sh frame lmi
LMI Statistics for interface Serial2 (Frame Relay DTE) LMI TYPE = ANSI
Invalid Unnumbered info 0 Invalid Prot Disc 0
Invalid dummy Call Ref 0 Invalid Msg Type 0
Invalid Status Message 0 Invalid Lock Shift 0
Invalid Information ID 0 Invalid Report IE Len 0
Invalid Report Request 0 Invalid Keep IE Len 0
Num Status Enq. Sent 14 Num Status msgs Rcvd 14
Num Update Status Rcvd 0 Num Status Timeouts 0
Router1#show interfaces s2
Serial2 is up, line protocol is up
Hardware is CD2430 in sync mode
MTU 1500 bytes, BW 115 Kbit, DLY 20000 usec, rely 255/255, load 1/255
Encapsulation FRAME-RELAY, loopback not set, keepalive set (10 sec)
LMI enq sent 15, LMI stat recvd 15, LMI upd recvd 0, DTE LMI up
LMI enq recvd 0, LMI stat sent 0, LMI upd sent 0
LMI DLCI 0 LMI type is ANSI Annex D frame relay DTE
FR SVC disabled, LAPF state down
Broadcast queue 0/64, broadcasts sent/dropped 52/0, interface

broadcasts 46
Last input 00:00:00, output 00:00:03, output hang never
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Last clearing of “show interface” counters never
Input queue: 0/75/0 (size/max/drops); Total output drops: 0
Queueing strategy: weighted fair
Output queue: 0/1000/64/0 (size/max total/threshold/drops)
Conversations 0/1/256 (active/max active/max total)
Reserved Conversations 0/0 (allocated/max allocated)
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
66 packets input, 4724 bytes, 0 no buffer
Received 0 broadcasts, 0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored, 0 abort
75 packets output, 5758 bytes, 0 underruns
0 output errors, 0 collisions, 5 interface resets
0 output buffer failures, 0 output buffers swapped out
2 carrier transitions
DCD=up DSR=up DTR=up RTS=up CTS=up
Router1#sh ip route
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B -
BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, * -
candidate default
U - per-user static route, o - ODR

Gateway of last resort is not set
10.0.0.0/24 is subnetted, 5 subnets
D 10.2.2.0 [90/2195456] via 10.140.1.1, 00:03:45, Serial1
D 10.3.3.0 [90/2195456] via 10.140.2.2, 00:03:46, Serial0
C 10.1.1.0 is directly connected, Ethernet0
C 10.140.2.0 is directly connected, Serial0
C 10.140.1.0 is directly connected, Serial1
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Router1#sh frame-relay traffic
Frame Relay statistics:
ARP requests sent 0, ARP replies sent 0
ARP request recvd 0, ARP replies recvd 0
Router1# show traffic-shape Æ shows traffic shaping related statistics
Access Target Byte Sustain Excess Interval
Increment Adapt
I/F List Rate Limit bits/int bits/int (ms)
(bytes) Active
Se2.1 56000 875 7000 0 125
875 BECN Æshows BECN is active
Se2.2 56000 7875 56000 56000 125
875 BECN
===================
Num Update Status Rcvd 0 Num Status Timeouts 0
===================
Router1#show frame-relay pvc
PVC Statistics for interface Serial2 (Frame Relay DTE)
DLCI = 100, DLCI USAGE = LOCAL, PVC STATUS = ACTIVE, INTERFACE =
Serial2.1

input pkts 215 output pkts 217 in bytes 17440
out bytes 17428 dropped pkts 0 in FECN pkts 0
in BECN pkts 0 out FECN pkts 0 out BECN pkts 0
in DE pkts 0 out DE pkts 0
out bcast pkts 215 out bcast bytes 17200
Shaping adapts to BECN Æ shows what type of traffic shaping used
pvc create time 00:26:06, last time pvc status changed 00:15:07
DLCI = 102, DLCI USAGE = LOCAL, PVC STATUS = ACTIVE, INTERFACE =
Serial2.2
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input pkts 205 output pkts 209 in bytes 16230
out bytes 17176 dropped pkts 0 in FECN pkts 0
in BECN pkts 0 out FECN pkts 0 out BECN pkts 0
in DE pkts 0 out DE pkts 0
out bcast pkts 206 out bcast bytes 16624
pvc create time 00:24:51, last time pvc status changed 00:14:28
====================
Router1#debug frame-relay lmi
Frame Relay LMI debugging is on
Displaying all Frame Relay LMI data
05:37:40: Serial2(out): StEnq, myseq 108, yourseen 107, DTE up
05:37:40: datagramstart = 0x647D20, datagramsize = 14
05:37:40: FR encap = 0x00010308
05:37:40: 00 75 95 01 01 01 03 02 6C 6B
05:37:40:
05:37:40: Serial2(in): Status, myseq 108
05:37:40: RT IE 1, length 1, type 1
05:37:40: KA IE 3, length 2, yourseq 108, myseq 108

05:37:51: Serial2(out): StEnq, myseq 109, yourseen 108, DTE up
05:37:51: datagramstart = 0x647D20, datagramsize = 14
05:37:51: FR encap = 0x00010308
05:37:51: 00 75 95 01 01 01 03 02 6D 6C
05:37:51:
05:37:51: Serial2(in): Status, myseq 109
05:37:51: RT IE 1, length 1, type 1
05:37:51: KA IE 3, length 2, yourseq 109, myseq 109 fram
======================
Router1#debug frame-relay
05:38:00: Serial2(out): StEnq, myseq 110, yourseen 109, DTE up
05:38:00: datagramstart = 0x647D20, datagramsize = 14
05:38:00: FR encap = 0x00010308
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05:38:00: 00 75 95 01 01 00 03 02 6E 6D
05:38:00:
05:38:00: Serial2(in): Status, myseq 110
05:38:00: RT IE 1, length 1, type 0
05:38:00: KA IE 3, length 2, yourseq 110, myseq 110
05:38:00: PVC IE 0x7 , length 0x3 , dlci 100, status 0x2
05:38:00: PVC IE 0x7 , length 0x3 , dlci 102, status 0x2 ip
05:38:10: Serial2(out): StEnq, myseq 111, yourseen 110, DTE up
05:38:10: datagramstart = 0x647D20, datagramsize = 14
05:38:10: FR encap = 0x00010308
05:38:10: 00 75 95 01 01 01 03 02 6F 6E
05:38:42: Serial2.2(o):Pkt sent on dlci 102(0x1861), pkt type
0x800(IP), datagramsize 64
05:38:43: Serial2.1: broadcast search

05:38:43: Serial2.1(o): dlci 100(0x1841), pkt type 0x800(IP),
datagramsize 64
05:38:43: broadcast dequeue
05:38:43: Serial2.1(o):Pkt sent on dlci 100(0x1841), pkt type
0x800(IP), datagramsize 64
05:38:46: Serial2(i): dlci 100(0x1841), pkt type 0x800, datagramsize 64
05:38:46: Serial2.1: Broadcast on DLCI 100 link 65(CDP)
05:38:46: Serial2.1(o): dlci 100(0x1841), pkt type 0x2000(CDP),
datagramsize 279
05:38:46: broadcast dequeue
05:38:46: Serial2.1(o):Pkt sent on dlci 100(0x1841), pkt type
0x2000(CDP), datagramsize 279
05:38:46: Serial2(i): dlci 102(0x1861), pkt type 0x800, datagramsize 64
05:38:46: Serial2.2: broadcast search
05:38:46: Serial2.2(o): dlci 102(0x1861), pkt type 0x800(IP),
datagramsize 64
05:38:46: broadcast dequeue
05:38:46: Serial2.2(o):Pkt sent on dlci 102(0x1861), pkt type
0x800(IP), datagramsize 64
05:38:47: Serial2.1: broadcast search
05:38:47: Serial2.1(o): dlci 100(0x1841), pkt type 0x800(IP),
datagramsize 64
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05:38:47: Serial2(i): dlci 100(0x1841), pkt type 0x2000, datagramsize
279
05:38:47: broadcast dequeue
05:38:47: Serial2.1(o):Pkt sent on dlci 100(0x1841), pkt type
0x800(IP), datagramsize 64

05:38:48: Serial2(i): dlci 102(0x1861), pkt type 0x2000, datagramsize
279
==================
Router1#show interfaces
Ethernet0 is up, line protocol is up
Hardware is Lance, address is 0010.7be8.7e84 (bia 0010.7be8.7e84)
Internet address is 10.1.1.3/24
MTU 1500 bytes, BW 10000 Kbit, DLY 1000 usec, rely 255/255, load
1/255
Encapsulation ARPA, loopback not set, keepalive set (10 sec)
ARP type: ARPA, ARP Timeout 04:00:00
Last input never, output 00:00:03, output hang never
Last clearing of “show interface” counters never
Queueing strategy: fifo
Output queue 0/40, 0 drops; input queue 0/75, 0 drops
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
0 packets input, 0 bytes, 0 no buffer
Received 0 broadcasts, 0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored, 0 abort
0 input packets with dribble condition detected
887 packets output, 72833 bytes, 0 underruns
0 output errors, 0 collisions, 3 interface resets
0 babbles, 0 late collision, 0 deferred
0 lost carrier, 0 no carrier
0 output buffer failures, 0 output buffers swapped out
================
Serial2 is up, line protocol is up
Hardware is CD2430 in sync mode
MTU 1500 bytes, BW 115 Kbit, DLY 20000 usec, rely 255/255, load 1/255

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Encapsulation FRAME-RELAY, loopback not set, keepalive set (10 sec)
LMI enq sent 138, LMI stat recvd 138, LMI upd recvd 0, DTE LMI up
LMI enq recvd 0, LMI stat sent 0, LMI upd sent 0
LMI DLCI 0 LMI type is ANSI Annex D frame relay DTE
FR SVC disabled, LAPF state down
Broadcast queue 0/64, broadcasts sent/dropped 623/0, interface
broadcasts 577
Last input 00:00:01, output 00:00:00, output hang never
Last clearing of “show interface” counters never
Input queue: 0/75/0 (size/max/drops); Total output drops: 0
Queueing strategy: weighted fair
Output queue: 0/1000/64/0 (size/max total/threshold/drops)
Conversations 0/1/256 (active/max active/max total)
Reserved Conversations 0/0 (allocated/max allocated)
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
759 packets input, 51726 bytes, 0 no buffer
Received 0 broadcasts, 0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored, 0 abort
768 packets output, 52560 bytes, 0 underruns
0 output errors, 0 collisions, 5 interface resets
0 output buffer failures, 0 output buffers swapped out
2 carrier transitions
DCD=up DSR=up DTR=up RTS=up CTS=up
Serial2.1 is up, line protocol is up
Hardware is CD2430 in sync mode
Description: frame relay to router b

Interface is unnumbered. Using address of Ethernet0 (10.1.1.3)
MTU 1500 bytes, BW 115 Kbit, DLY 20000 usec, rely 255/255, load 1/255
Encapsulation FRAME-RELAY
Serial2.2 is up, line protocol is up
Hardware is CD2430 in sync mode
Description: frame relay to router c
Interface is unnumbered. Using address of Ethernet0 (10.1.1.3)
MTU 1500 bytes, BW 115 Kbit, DLY 20000 usec, rely 255/255, load 1/255
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Encapsulation FRAME-RELAY
Serial3 is administratively down, line protocol is down
Hardware is CD2430 in sync mode
MTU 1500 bytes, BW 115 Kbit, DLY 20000 usec, rely 255/255, load 1/255
Encapsulation HDLC, loopback not set, keepalive set (10 sec)
Last input never, output never, output hang never
Last clearing of “show interface” counters never
Input queue: 0/75/0 (size/max/drops); Total output drops: 0
Queueing strategy: weighted fair
Output queue: 0/1000/64/0 (size/max total/threshold/drops)
Conversations 0/0/256 (active/max active/max total)
Reserved Conversations 0/0 (allocated/max allocated)
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
0 packets input, 0 bytes, 0 no buffer
Received 0 broadcasts, 0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored, 0 abort
0 packets output, 0 bytes, 0 underruns
0 output errors, 0 collisions, 3 interface resets

0 output buffer failures, 0 output buffers swapped out
0 carrier transitions
DCD=down DSR=down DTR=down RTS=down CTS=down
Router1#show frame-relay lmi
LMI Statistics for interface Serial2 (Frame Relay DTE) LMI TYPE = ANSI
Invalid Unnumbered info 0 Invalid Prot Disc 0
Invalid dummy Call Ref 0 Invalid Msg Type 0
Invalid Status Message 0 Invalid Lock Shift 0
Invalid Information ID 0 Invalid Report IE Len 0
Invalid Report Request 0 Invalid Keep IE Len 0
Num Status Enq. Sent 139 Num Status msgs Rcvd 139
Num Update Status Rcvd 0 Num Status Timeouts 0
Router1#sh frame-relay pvc
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PVC Statistics for interface Serial2 (Frame Relay DTE)
DLCI = 100, DLCI USAGE = LOCAL, PVC STATUS = ACTIVE, INTERFACE =
Serial2.1
input pkts 321 output pkts 324 in bytes 25944
out bytes 25996 dropped pkts 0 in FECN pkts 0
in BECN pkts 0 out FECN pkts 0 out BECN pkts 0
in DE pkts 0 out DE pkts 0
out bcast pkts 322 out bcast bytes 25768
Shaping adapts to BECN
pvc create time 00:33:42, last time pvc status changed 00:22:43
DLCI = 102, DLCI USAGE = LOCAL, PVC STATUS = ACTIVE, INTERFACE =
Serial2.2
input pkts 311 output pkts 314 in bytes 24734
out bytes 25401 dropped pkts 0 in FECN pkts 0

in BECN pkts 0 out FECN pkts 0 out BECN pkts 0
in DE pkts 0 out DE pkts 0
out bcast pkts 311 out bcast bytes 24849
pvc create time 00:32:27, last time pvc status changed 00:22:04
Router1#sh frame-relay map
Serial2.1 (up): point-to-point dlci, dlci 100(0x64,0x1840), broadcast
shows the mapping of DLCI
status defined, active
Serial2.2 (up): point-to-point dlci, dlci 102(0x66,0x1860), broadcast
status defined, active
Router1#show frame-relay traffic
Frame Relay statistics:
ARP requests sent 0, ARP replies sent 0
ARP request recvd 0, ARP replies recvd 0
Router1#
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ATM Connections
This section covers ATM connectivity in wide area networks, where ATM is
very widely used. Major telecommunication carriers build voice and data
backbones using ATM technology. The major benefits of ATM are Quality of
Service (QoS), which is required for voice and video traffic. ATM provides
fixed size cells of 53 bytes. These cells consist of a 5-byte header and a 48-
byte payload. The fixed cell size provides predictability and allows ATM to
operate extremely efficiently. ATM is especially useful for time-delay sensi-
tive applications such as voice and video.
ATM Overview
ATM is the building block of Broadband ISDN (B-ISDN) services. The devel-
opment of optical technologies was a major consideration in its technolo-

gies. ATM is a technology developed to address the needs of both voice and
data technologies; in voice technologies, there should be guaranteed band-
width on a per call basis for a call to be reliable. In data technologies, the
traffic is bursty. Voice packets are usually small compared to data packets.
To address the requirements of both, ATM Forum and other standards org-
anizations agreed to 53-byte cell, with a 5-byte header, and 48-byte pay-
load. ATM technologies scales well at higher speeds like OC-3, OC-12, etc.
Some of the features of ATM are:
■
The edge devices provide error and flow control.
■
There is no error control on data field within the network, due to
low transmission error rates on fiber.
■
There is no flow control on links within the network.
■
It is connection-oriented at the lowest level.
■
All information is transferred in a virtual circuit assigned for the
duration of the connection.
■
A fixed cell (packet) size permits high-speed switching nodes.
■
There is no constraint on data services (segmentation).
■
It has an efficient cell structure for bandwidth allocation, and
quality of service.
ATM Packet Format
Table 7.8 depicts the ATM cell format.
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Table 7.8 ATM Cell Format
Header 5 bytes (8 bits = 1 byte) Payload 48 bytes
GFC VPI VCI PTI CLP HEC
4 bits 8 bits 16 bits 3 bits 1 bit 8 bits Data
GFC Generic Flow
VPI Virtual Path Identifier—VPI is 8 bits, which gives 256 virtual paths
VCI Virtual Circuit Identifier—VCI is 16 bits, which gives 65K virtual circuits
PTI Payload Type Indicator
CLP Cell Loss—CLP is the cell loss priority bit, which if set, can discard
the packet. This is similar to the DE (Discard Eligibility) bit in Frame Relay
HEC Header Error Control—HEC is the check sum error control on the
header itself. HEC is also used as a synchronizing delimiter; after three
HEC matches the transmission is synchronized
Payload Data
ATM Adaptation Layer (AAL)
The ATM Adaptation Layer (AAL) provides mapping of higher layer applica-
tion data to and from the ATM cell. The services AAL provides are a SAR
(Segmentation Assembly and Re-assembly) layer; also it detects lost cells and
errors in cells through a 4-bit sequence number protection. Several AAL
types are defined, with each type consisting of a separate SAR sublayer:
■
AAL Type 1 Used for connection-oriented, constant-bit-rate
services and is used for circuit emulation.
■
AAL Type 2 Used for connection-oriented, variable-bit-rate
services, and is used for video applications.
■
AAL Type 3/4 AAL Type 3 and 4 are combined; they are designed

for data applications and support both connectionless and connec-
tion oriented applications.
■
AAL Type 5 A more commonly used protocol, applied to VBR
(Variable Bit Rate) type traffic. AAL Type 5 is used for signaling
and frame relay over ATM.
The AAL provides the benefits of error detection, circuit emulation, and
connectionless or connection-oriented services depending on the type of
AAL used.
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ATM Virtual Circuits
ATM virtual circuits are built on top of a VPI/VCI combination. A VC
bundle inside of a VP is used to differentiate traffic (like voice, video, and
data). VPI/VCI are significant on a physical link between a pair of ATM
switches. These circuits are unidirectional, and need mapping in reverse
directions to complete conversation between two end-node devices. Circuits
can be established as PVCs or SVCs. More popularly used circuits are
PVCs, which need mapping and configuration at each ATM switch along
the path. SVCs are more dynamic; hence they build and tear the sessions
automatically.
Figure 7.17 illustrates that on a given physical ATM network, the VP
are the virtual paths that are uniquely identified through VPI. In every vir-
tual path, multiple virtual channels can be defined. VPI is 8 bits long (256
virtual paths), and VCI is 16 bits long (64K circuits), thus providing 256*
64k circuits. The number of channels available gives the granularity
needed to provide QoS. Each circuit is a VPI/VCI combination. VPI zero
(VPI=0) is reserved.
PVC Mapping and Circuit Buildup

Table 7.8 and Figure 7.18 demonstrate the process of PVC mapping and
circuit buildup. Notice how the Ports, VCI, and VPI in the table relate and
map to the switch diagram. Remember PVCs need to be manually config-
ured on each switch.
Table 7.8 PVC mapping and circuit emulation.
Input Port VPI VCI Port Output VPI VCI
1 10202 20 10
2 20101 10 20
3 30154 31 16
4 40163 30 15
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Figure 7.17 VPI/VCI circuit emulation.
Physical Circuit
VP
VP
VP
VP
VC
VC
VC
VC
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In the case of Cisco routers with an AIP ATM interface, the PVCs are
mapped point-to-point, or point-to-multipoint.
Configuring ATM
Configuring routers for ATM is similar to any other interface on Cisco
routers. Set up the interface subsystem in the configuration mode, by
typing the interface-related detailed syntax. Figure 7.19 illustrates how to
build an ATM network; configurations follow in Figures 7.20 and 7.21.

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Figure 7.18 PVC mapping and circuit buildup.
ATM switch 1 ATM switch 2
ATM switch 3
S1,P 2 going to P1
of sw3 with
VPI=20,VCI=10
Vpi=10,vci=
20 comming
to P1, sw1
Vpi=30,vci=15
comming toP3 -
SW1-P1-SW2
P4 SW1 going to
P3 of sw3 with
VPI=31,VCI=16
Figure 7.19 ATM network.
Central 1
E0
AIP1/0
ATM
Router1
E0 10.1.1.1/24
ATM1/0 192.168.101.1/24
ISDN No 111111
Branch 1
E0
AIP1/0
Branch1-1
E0 192.168.2.1/24

ATM 1/0 192.168.102.1/24
ISDN No 222222
Host A
192.168.2.2
SERVER
A
10.1.1.2
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294 Chapter 7 • Configuring and Backing Up Permanent Connections
Figure 7.20 Router1 configuration.
Router1
!
version 12.0
service timestamps debug uptime
service timestamps log uptime
no service password-encryption
!
hostname Router1
!
!
network-clock base-rate 56k
ip subnet-zero
no ip domain-lookup
!
controller T1 0
framing esf
clock source internal
linecode b8zs
mode atm
!

!
process-max-time 200
!
interface Ethernet0
ip address 10.0.2.1 255.255.255.0
no ip directed-broadcast
!
interface ATM0 Æ This command provides the configuration mode for atm
interface
no ip address
no ip directed-broadcast
no atm ilmi-keepalive
!
interface ATM0.1 point-to-point – defines atm sub interface
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Continued
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Configuring and Backing Up Permanent Connections • Chapter 7 295
Figure 7.20 Continued.
ip address 10.0.23.2 255.255.255.0
no ip directed-broadcast
pvc my-data-pvc 0/100 – creates PVC
ubr 64
encapsulation aal5snap
!
no ip address
no ip directed-broadcast
shutdown
!
router igrp 1

network 10.0.0.0
!
ip classless
no ip http server
!
end
Figure 7.21 Router2 configuration.
Router2
!
version 12.0
service timestamps debug uptime
service timestamps log uptime
no service password-encryption
!
hostname Router2
!
!
network-clock base-rate 56k
ip subnet-zero
no ip domain-lookup
!
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Continued
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296 Chapter 7 • Configuring and Backing Up Permanent Connections
Figure 7.20 Continued.
controller T1 0
framing esf
linecode b8zs
mode atm

!
!
process-max-time 200
!
interface Ethernet0
ip address 10.0.3.1 255.255.255.0
no ip directed-broadcast
!
interface ATM0
no ip address
no ip directed-broadcast
no atm ilmi-keepalive
!
interface ATM0.1 point-to-point
ip address 10.0.23.3 255.255.255.0
no ip directed-broadcast
pvc my-data-pvc 0/100
ubr 64
encapsulation aal5snap
!
!
!
router igrp 1
network 10.0.0.0
!
ip classless
no ip http server
!
end
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Configuring and Backing Up Permanent Connections • Chapter 7 297
Verifying and Troubleshooting ATM
Connections
The methodology applied in troubleshooting ATM networks is by using
show and debug commands relevant to ATM. Various commands that can
be used to monitor an ATM network include the following:
Router1#show atm ?
arp-server ATM ARP Server Table
class-links ATM vc-class links
ilmi-configuration Display Top level ILMI
ilmi-status Display ATM Interface ILMI information
interface Interfaces and ATM information
map ATM static mapping
pvc ATM PVC information
signalling ATM Signaling commands
svc ATM SVC information
traffic ATM statistics
vc ATM VC information
vp ATM VP information
Router1#show int atm 0
ATM0 is up, line protocol is up
Hardware is PQUICC Atom1
MTU 1500 bytes, sub MTU 1500, BW 1536 Kbit, DLY 20000 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ATM, loopback not set -Æshows the encapsulation mode
on the interface
Keepalive not supported
Encapsulation(s):, PVC mode
1024 maximum active VCs, 2 current VCCs Æ shows Virtual channels

supported
VC idle disconnect time: 300 seconds
Last input 00:00:00, output never, output hang never
Last clearing of “show interface” counters never
Input queue: 0/75/0 (size/max/drops); Total output drops: 0
Queueing strategy: weighted fair
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298 Chapter 7 • Configuring and Backing Up Permanent Connections
Output queue: 0/1000/64/0 (size/max total/threshold/drops)
Conversations 0/0/256 (active/max active/max total)
Reserved Conversations 0/0 (allocated/max allocated)
5 minute input rate 0 bits/sec, 0 packets/sec
5 minute output rate 0 bits/sec, 0 packets/sec
13 packets input, 1008 bytes, 0 no buffer
Received 0 broadcasts, 0 runts, 0 giants, 0 throttles
0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored, 0 abort
15 packets output, 1166 bytes, 0 underruns
0 output errors, 0 collisions, 2 interface resets
0 output buffer failures, 0 output buffers swapped out
The following command shows the details on the sub-interface atm 0.1.
Router1# show int atm 0.1
ATM0.1 is up, line protocol is up
Hardware is PQUICC Atom1
Internet address is 10.0.23.2/24
MTU 1500 bytes, BW 1536 Kbit, DLY 20000 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ATM
12 packets input, 874 bytes
15 packets output, 1106 bytes

0 OAM cells input, 0 OAM cells output
The following command shows traffic across the ATM link.
Router1#SHOW ATM traffic
13 Input packets
14 Output packets
0 Broadcast packets
0 Packets received on non-existent VC
0 Packets attempted to send on non-existent VC
0 OAM cells received
F5 InEndloop: 0, F5 InSegloop: 0, F5 InAIS: 0, F5 InRDI: 0
F4 InEndloop: 0, F4 InSegloop: 0, F4 InAIS: 0, F4 InRDI: 0
0 OAM cells sent
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Configuring and Backing Up Permanent Connections • Chapter 7 299
F5 OutEndloop: 0, F5 OutSegloop: 0, F5 OutRDI: 0
F4 OutEndloop: 0, F4 OutSegloop: 0, F4 OutRDI: 0
0 OAM cell drops
The following command shows the PVC status.
Router1#show atm pvc
On ATM 0.1 interface , my-data-pvc has VPI=0, VCI =100, encapsulation
is SNAP.
Router1#show atm pvc
VCD / Peak Avg/Min Burst
Interface Name VPI VCI Type Encaps SC Kbps Kbps
Cells Sts
0.1 my-data-pv 0 100 PVC SNAP UBR 64 UP
0.2 my-voice-p 0 200 PVC VOICE VBR 384 192
48 UP (192)
The following command shows the mapping between IP address and

PVC.
Router1#show atm pvc map
Map list ATM0.1_ATM_INARP : DYNAMIC
ip 10.0.23.3 maps to VC 1, VPI 0, VCI 100, ATM0.1
ATM Debug Commands:
Router1#debug atm ?
aal-crc Display CRC error packets
arp Show ATM ARP events
compress ATM Compression
errors ATM errors
events ATM or FUNI Events
ilmi Show ILMI events
oam Dump OAM Cells
packet ATM or FUNI packets
pvcd Show PVCD events
sig-all ATM Signalling all
sig-api ATM Signalling api
sig-error ATM Signalling errors
sig-events ATM Signalling events
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300 Chapter 7 • Configuring and Backing Up Permanent Connections
sig-ie ATM Signalling information elements
sig-packets ATM Signalling packets
smap-all ATM Signalling Static Map all
smap-error ATM Signalling Static Map errors
smap-events ATM Signalling Static Map events
state ATM or FUNI VC States
Let’s look at some ATM debug commands that will further aid in trou-
bleshooting ATM implementations.

The debug atm packet Command
The debug atm packet command will display all ATM packets.
Router1#debug atm packet
ATM packets debugging is on
Displaying all ATM packets
Router1#conf t
Enter configuration commands, one per line. End with CNTL/Z.
Router1(config)#int atm 0
Router1(config-if)#shut
Router1(config-if)#no shut
Router1(config-if)#exit
Router1(config)#exit
Router1#sho log
Syslog logging: enabled (0 messages dropped, 0 flushes, 0 overruns)
Console logging: disabled
Monitor logging: level debugging, 0 messages logged
Buffer logging: level debugging, 351 messages logged
Trap logging: level informational, 47 message lines logged
Log Buffer (4096 bytes):
04:45:47: %SYS-5-CONFIG_I: Configured from console by console
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Configuring and Backing Up Permanent Connections • Chapter 7 301
04:46:06: %LINK-5-CHANGED: Interface ATM0, changed state to
administratively down
04:46:07: %LINEPROTO-5-UPDOWN: Line protocol on Interface ATM0, changed
state to down
04:46:21: ATM0.1(O):
VCD:0x1 VPI:0x0 VCI:0x64 DM:0x100 SAP:AAAA CTL:03 OUI:000000 TYPE:0800
Length:0x56

Shows the 1/100 (64hex) pvc sending an ip packet type0800.
04:46:21: 45C0 004A 0000 0000 0209 96EA 0A00 1702 FFFF FFFF 1105 0001
0003 0000 0000
04:46:21: 53C9 0002 0000 0064 0003 E805 DCFF 0100 0003 00FF FFFF 0100
0501 1043 6973
04:46:21: 0017 0000 07D0 0019 6E05 DCFF 0100
04:46:21:
04:46:22: ATM0.1(O): —o –Outgoing packet
VCD:0x1 VPI:0x0 VCI:0x64 DM:0x100 SAP:AAAA CTL:03 OUI:000000 TYPE:0806
Length:0x20
Arp packet type 0806
04:46:22: 0013 0800 0000 0008 0400 0004 0A00 1702 0000 0000
04:46:22:
04:46:22: ATM0.1(I):
VCD:0x1 VPI:0x0 VCI:0x64 Type:0x0 SAP:AAAA CTL:03 OUI:000000 TYPE:0806
Length:0x20
04:46:22: 0013 0800 0000 0009 0400 0004 0A00 1703 0A00 1702
04:46:22:
04:46:23: %LINK-3-UPDOWN: Interface ATM0, changed state to up
04:46:24: %LINEPROTO-5-UPDOWN: Line protocol on Interface ATM0, changed
state to up
04:46:25: %SYS-5-CONFIG_I: Configured from console by console
04:46:34: ATM0.1(I):
VCD:0x1 VPI:0x0 VCI:0x64 Type:0x0 SAP:AAAA CTL:03 OUI:000000 TYPE:0800
Length:0x56
04:46:34: 45C0 004A 0000 0000 0109 97E9 0A00 1703 FFFF FFFF 1101 0001
0003 0000 0000
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