CCNP BSCI Exam Certification Guide (CCNP Self-Study), Second Edition

Clare Gough, Cisco Press

ISBN:1587200783, Edition: 2nd, 2003-02-11

Price: $49.95

Table of Contents

Chapter 1
Cisco Certifications, the BSCI Exam, and This Book`s Features 3

Chapter 2
Managing Scalable Network Growth 27

Chapter 3
IP Addressing 83

Chapter 4
IP Routing Principles 157

Chapter 5
Using OSPF in a Single Area 205

Chapter 6
Using OSPF Across Multiple Areas 283

Chapter 7
Configuring the Integrated IS-IS Protocol 339

Chapter 8
Using EIGRP in Enterprise Networks 423

Chapter 9
Connecting to Other Autonomous Systems-The Basics of BGP-4 483

Chapter 10
Implementing and Tuning BGP for Use in Large Networks 539

Chapter 11
Controlling Routing Updates Across the Network 593

Chapter 12
Scenarios for Final Preparation 665

Appendix A
Answers to Quiz Questions 771

Appendix B
Sample Configurations 843

Appendix C

Glossary 859

Index 903

I N D E X

A
ABRs (Area Border Routers), 292
LSA propagation, 294
Access layer, hierarchical designs, 42
access lists. See also IP access lists BGP-4, 557
controlling terminal access, 51-52
guidelines for writing, 48
prioritization, 54-55
security, 51
writing guidelines for, 49
accessibility, network requirements, 34
ACRC (Advanced Cisco Router Configuration), 5, 17
AD (advertised distance), 439
adaptability, network requirements, 34
adding networks to topology tables, 443
addresses classes of, 92
Internet, 92
Integrated IS-IS, 354-355
NETs, 356-357
NSAPs, 356
IP addresses. See IP addresses major, 92
network, 89-92
NIC addresses, 91
summarization, 113
supernet addresses, 92
translating, 125-126
VLSM addresses, allocating, 107
addressing schemes, case studies, 88
adjacencies Integrated IS-IS, 345, 361-362
establishing on broadcast links, 362
establishing on NBMA links, 363
establishing on point-to-point links, 362
OSPF, 180, 217
administrative distance configuring, 619-620
path selection between routing protocols, 181-183, 610-612
Advanced Cisco Router Configuration. See ACRC advantages of CIDR, 101-103
of OSPF neighbors, 218
of policy routing, 637-638
of summarization, 112, 132
of VLSM, 104
bit allocation, 107
VLSM addresses, 107
advertised distance, 439
advertising routes from BGP-4 to IGP, 571-572
from IGP to BGP-4, 571
aggregate-address command, 571
aggregated routes, 109
autonomous systems, 509
Aggregator attribute (BGP-4), 502
alleviating network congestion, 43
allocating VLSM addresses, 107
alternatives to connecting to ISP, 512-513
to summarization, 115
answers to scenario 11-1, 671-673
to scenario 11-2, 673-674
to scenario 11-3, 675, 677
to scenario 11-4 Part A, 683, 685-686
to scenario 11-4 Part B, 688-689
to scenario 11-4 Part C, 720, 722-724
to scenario 11-5 Part C, 766-768
to scenario 11-5 Part A, 726-728
to scenario 11-5 Part B, 728, 730-731
to scenario 11-5 Part C, 765-769
AppleTalk. EIGRP configuration, 461
applications, delays in, 40
Area 0, 292
Area Border Routers. See ABRs area boundaries, multiple areas, 290
area range command, 304-305
area routing, 358-360
areas,, 297-299, 345
backbone areas, 298
design considerations, 377-378
NSSAs, 298
stubby areas, 298
AS external ASBR summary link, LSAs, 294
AS_Path attribute (BGP-4), 502,904
ASBRs (Autonomous System Boundary Routers), 292
LSA propagation, 294
OSPF summarization command, 305
assigning IP VLSM subnets to WAN connections, 116-117
Atomic Aggregate attribute (BGP-4), 502
attributes BGP-4
local preference, 565
policy routing, 500-503
verifying configurations, 567, 569-570
weight, 564
OSPF, 180
automatic summarization, 113
autonomous switching, 171
Autonomous System Boundary Routers. See ASBRs autonomous systems, 176
configuring, 507
defined, 490
defining networks to be advertised, 508
identifying neighbors and peer groups, 508
Next-Hop addresses, forcing, 508
routes, aggregating, 509
routing processes, starting, 508
synchronization, disabling, 509
avoiding routing loops, 612-614

B
backbone areas, 292, 298
backbone routers, 292
backup designated routers, 218
bandwidth, configuring over NBMA, 457-458
bandwidth command, 239, 456-457
using in WANs with EIGRP, 457
bandwidth-percent command, 459
baselines, 49
best path selection, Integrated IS-IS, 375-376
BGP-4, 483, 488-489
access lists, 557
advertising routes from BGP-4 to IGP, 571-572
from IGP to BGP-4, 571
attributes local preference, 565
verifying configurations, 567-570
weight, 564
autonomous systems, 490
case studies, 488-489, 544
characteristics of, 491
CIDR, 496
commands for tuning, 564
configuring default metrics, 617
controlling traffic, 556
designing networks, 545
determining paths by tuning attributes, 564
distribute lists, 557
external BGP-4, 492
fully meshed networks, 546
internal BGP-4, 492
key features of, 515-520
message types, 492
Next Hop attribute, 503, 505
operations overview, 491
policy routing, 490
attributes, 500-503
disadvantages of, 499
rules of, 497
prefix lists, 557-558
redistributing between IGP, 570
route aggregation, 496-497
route maps, 557
route selection, 505-507
synchronization, 494
verifying configurations, 510-511
when not to use, 511
bit allocation network addresses, 94
VLSM, 107
Border Gateway Protocol 4. See BGP-4
broadcast mode, OSPF, 244
broadcast multiaccess OSPF network topologies, 214
Next Hop attribute, 505
BSCI (Building Cisco Scalable Internetworks), 5-6
how to use this book if you have taken this course, 17
prerequisites for, 5
Building Cisco Scalable Internetworks. See BSCI building OSPF routing tables, 221-222
ASBRs (Autonomous System Boundary Routers) 905

C
calculating cost of path selection, 296-297
case studies addressing schemes, 88
BGP-4, 488-489, 544
EIGRP, 429
inadequate networks, 32-33
OSPF, 211
in multipe area networks, 289
redistribution, 599
examples of, 627-633
routing protocols, 162
VLSM, 105-107
CBWFQ (class-based weighted fair queuing), 55
CCDP (Cisco Certified Design Professional), 3
CCIE (Cisco Certified Internetworking Expert), 6-7
CCNA/CCDA certification, 7
CEF (Cisco Express Forwarding), 171
certifications, 6-7
CCIE, 6-7
CCNA/CCDA, 7
CCNP/CCDP, 7
exams, 9
routing and switching career tracks, 7
changing default metrics with cost command, 238-239
characteristics of BGP-4, 491
of Layer 3 addresses, 90
of policy routing, 637
of route maps, 634-635
of route reflectors, 549-550
Charter List, BGP-4 attributes, 503
checking OSPF configurations in multiarea networks, 315
show ip ospf border-routers command, 316
show ip ospf virtual-links command, 317-318
OSPF configurations on a single router, 246, 250
show ip ospf command, 247
show ip ospf database command, 248
show ip ospf interface command, 250-252
show ip ospf neighbor command, 252-254
show ip protocols command, 255-256
show ip route, 257
choosing successors, 442-443
topologies, OSPF, 232
CIDR (classless interdomain routing), 98, 496
advantages of, 101-103
BGP-4, 496
definition of, 98
example of, 100-101, 131
example of use in case study, 101
IP addressing and the Internet, 99
summary of, 130
circuits, 345
Cisco Certified Design Professional. See CCDP Cisco Certified Internetworking Expert. See CCIE
Cisco Express Forwarding (CEF), 58, 171
Cisco Networking Academy Courses, study guidelines upon completion, 17-18
Cisco routers. See also routers, 43
alleviating congestion with IP access lists, 43
routing/switching relationships, 170-171
Cisco Technical Assistance Center. See TAC
class-based weighted fair queuing (CBWFQ), 55
classes of IP addresses, 92-93
classful IP routing protocols, 171
classful routing, 97, 171
classless interdomain routing. See CIDR
classless routing protocols, 171-172
clients placement of for controlling network traffic, 59
unable to connect to network resources, 40
CLNP (Connectionless Network Protocol), 345
CLNS (Connectionless Network Service), 346
CLV (Code/Length/Value), 345
commands, 316
access-class, 52
access-group, 52
access-list, 45-46
aggregate-address, 571
area range, 304
auto-cost, 239
auto-cost reference-bandwidth, 239
bandwidth, 239, 456-458
bandwidth-percent, 459
cost, 238-239
debug, 401-402
debug commands for EIGRP, 465
debug ip bgp, 510
debug IP OSPF adjacency, 222
debug ip policy, 646
default metric, 618
commands 906
deny any, 45, 49
distance, 631
distribute-list, 627
for configuring multiarea OSPF networks, 302
area range command, 304-305
network command, 302-303
summarization command, 305
for configuring OSPF on internal routers, 234
for monitoring policy routing, 645
for tuning BGP-4, 564
ip access-group, 45
ip classless, 632
ip forward-protocol, 60
ip helper-address, 60
ip ospf cost, 239
ip ospf network, 242
ip ospf network non-broadcast, 244
ip unnumbered, 113
match route map, 634
neighbor, 244
no ip address, 245
no-summary, 308
ospf auto-cost, 239
ospf neighbor, 243
passive interface, 622
priority, 55, 240
redistribute, 617
redistribute connected subnets, 236
route-map, 635
router ospf process number, 235
set route map, 634
show buffers, 35
show clns interface, 393-395
show clns neighbors, 391-393
show cpu process, 291
show interface, 35, 457
show ip bgp, 510, 567
show ip bgp neighbors, 510
show ip bgp paths, 510
show ip bgp summary, 510
show ip eigrp neighbors, 462
show ip eigrp topology, 462-464
show ip eigrp topology all, 462
show ip eigrp traffic, 462-464
show ip ospf, 246-248
show ip ospf border-routers, 315-317
show ip ospf command, 247
show ip ospf database, 246-250
show ip ospf interface, 246, 250-252
show ip ospf neighbor, 222, 246, 252-254
show ip ospf virtual-links, 315-318
show ip prefix-list, 559-560
show ip protocols, 246, 255-256
show ip route, 167-168, 246, 257
show ip route eigrp, 465
show ipx route, 462
show isis database, 396-397
show isis database detail, 397-399
show isis spf-log, 400-401
show memory, 291
show queuing, 35
stop telnet, 48
sub net zero, 107
summarization, 305
summary-only, 509
syntax conventions, 20
traceroute, 644
tunnel interface, 63
variance, 454-456
vty commands, 52
Community attribute (BGP-4), 503
configuring administrative distance, 619-620
autonomous systems, 507
bandwidth over NBMA clouds, 457-458
default metrics, 617-618
EIGRP, 451
for AppleTalk, 461
for IPX, 459-461
optional commands, 454-459
required commands, 452-453
Integrated IS-IS, 380-381
NMBA, 386-388
routing level, 381-383
summarization, 384-386
multiple routing protocols, problems with, 607
null interfaces, 55
OSPF, 234
area range command, 304-305
in broadcast mode, 244
in multiarea networks, 302, 314
in NBMA mode, 242-243
in point-to-multipoint mode, 244
in point-to-point mode on a Frame Relay subinterface, 245
network command, 302-303
on internal routers, 234-240
Community attribute (BGP-4) 907
on a single router, 240
stub areas, 307
summarization command, 305
totally stubby areas, 308
virtual links, 311
prefix lists BGP-4, 558
verifying configurations, 559-560
redistribution, 615-617
route maps for policy routing, 640
router ID, 238
virtual links, 312
contents of BSCI exam, 9-12
controlling BGP-4 traffic, 556
network traffic CEF, 58
design of client/server network, 59
EIGRP, 60
IP helper address, 59
silicon switching, 58
tunneling into IP, 61-62
with CPUs, 58
routing updates redistribution, 601-602
with filtering, 625-627
terminal access, 51-52
conventions for command syntax, 20
convergence, 183
EIGRP, 184
IGRP, 184
OSPF, 185
RIPv1, 183
Core layer, 42
cost, 238-239
of path selection, calculating (OSPF), 297
count to infinity, RIPv1, 177
CPUs, controlling network traffic, 58
creating networks, 40
hierarchical designs, 41
scaling, 41
prefix lists, 558
CSNP (complete sequence number packet), 345
custom queuing, 54

D
debug command, 401-402
BGP-4, 510
debug commands, 465
debug ip bgp, 510
debug ip ospf adjacency, 222
debug ip policy, 646
decision process (Integrated IS-IS), 375-376
default metric command, 618
default metrics, configuring, 238, 617-618
default routes, 164, 601
EIGRP, 624
IGRP, 624
redistribution, 623-624
when to use, 624
delays, 40
designated routers backup designated routers, 218
determining with priority command, 240
electing, 219-221
OSPF, 219-221
OSPF neighbors, 218
purpose for, 219
designing BGP-4 networks, 545
client server networks, controlling network traffic, 59
Integrated IS-IS areas, 377-378
IP networks, 118-123
private addresses, 124-125
OSPF networks in multiple areas, 299
destination address rotary translation, NAT, 127
determining area boundaries, 290
BGP-4 paths by tuning attributes, 564
designated router with priority command, 240
policy-based routes, 638
DHCP (Dynamic Host Configuration Protocol), 89, 123
Diffusing Update Algorith. See DUAL
Dijkstra algorithm, 185, 226
DIS (designated intermediate system), 346
disabling sychronization, 509
disadvantages of fully meshed networks, 546
of OSPF in a single area, 290
of policy routing, 499, 638
disadvantages 908
discontiguous networks, summarization, 114-115
discovering OSPF routes, 224-226
distance command, 631
distance vector protocols, 172-173
EIGRP, 173
IGRP, 178-179
metrics, 173
routing loops, 173
distribute lists, 53, 625
BGP-4, 557
distribute-list command, 627
Distribution layer, 42
distribution lists, controlling routing updates, 602
DNS (Domain Name System), 123
dotted decimal form, 95
down state, 223
DUAL (Diffusing Update Algorithm), 173
EIGRP, 439
updating routing tables in active mode, 441-443, 445-446, 449
updating the routing table in passive mode, 440
Dual IS-IS. See Integrated IS-IS
Dynamic Host Configuration Protocol. See DHCP
dynamic routes, 164
dynamic source address translation, NAT, 127

E
efficient networks, criteria for, 34
EGP (External Gateway Protocol), configuring default metrics, 617
EIGRP (Enhanced Interior Gateway Routing Protocol)), 423, 429
administrative distance, configuring, 620
autonomous system number, 452
bandwidth command, using in WANs, 457
case studies, 429
choosing successors, 442-443
configuring, 451
for AppleTalk, 461
for IPX, 459, 461
optional commands, 454-459
required commands, 452-453
configuring default metrics, 618
controlling network traffic, 60
convergence, 184
default routes, 624
defaults in bandwidth utilization, 456
defined, 429
distance vector protocols, 173
DUAL, 439
updating routing tables in active mode, 441-449
updating routing table in passive mode, 440
finding alternative paths to remote networks, 446, 449
hello protocol, 434
neighbor tables, 434-435
neighbors, 434
topology tables, 436-438
load balancing, 454
metrics, 438-439
operation of, 430-431
scaling, 449-450
solutions to issues, 450-451
summarization, 454, 727
terminology, 432-433
verifying operations, 462
debug commands, 465
show ip eigrp neighbors command, 462
show ip eigrp topology command, 463
show ip eigrp traffic command, 464
electing designated routers, 219-221
enabling OSPF routing protocol, 235
Enhanced Interior Gateway Routing Protocol. See EIGRP
examples of prefix lists, 559
of redistribution, 627-633
exams (certification), strategies for taking, 21-22
exchange process, finding OSPF neighbors, 222-223
exchange state, 224
exstart state, 224
extended IP access lists, 46-48
extended ping, 645
exterior routing protocols, 176
external BGP-4, 492
external link LSAs, 294
external summarization, 300
discontiguous networks, summarization 909

F
fast switching, 171
policy-routed traffic, 643
FC (feasibility condition), 442
FD (feasible distance), 439
feasible successors, 442
features of NAT, 127-128
of redistribution, 604
default redistribution between routing protocols, 604-606
multiple protocols, 606-607
filter configuration, verifying, 49
filtering routing updates, 625-627
finding alternative paths to remote networks, 446, 449
first octet rule, 96
floating static routes, 183
flooding, 91
format of Hello packets (Integrated IS-IS), 365-366
LSPs, 367-368
NSPs, 368-369
forwarding databases. See routing tables forwarding process (Integrated IS-IS), 377
Frame Relay, OSPF topologies NBMA, 232
point-to-point mode, 245
full state, 224
fully meshed IBGP-4 networks, route reflectors, 546-548

G
goals of this book, 4
guidelines for avoiding routing loops, 614
for writing access lists, 48-49

H
hello packets Integrated IS-IS, 364-366
OSPF, 216-217
hello protocol, 214
EIGRP, 434
becoming neighbors, 434
neighbor tables, 434-435
topology tables, 436-438
hiding network summarization changes, 112
hierarchical designs creating networks, 41
networks, 41
Access layer, 42
Core layer, 42
creating, 41
design rules for layers, 42
Distribution layer, 42
holddown, RIPv1, 177
hops, 173
host addressing IP addresses, 92

I-J
IANA (Internet Assigned Numbers Authority), 93
IBGP-4 fully meshed networks, 547
ICANN (Internet Corporation for Assigned Names and Numbers), 93
ICND (Interconnecting Cisco Network Devices), 6, 27
ICRC (Introduction to Cisco Router Configuration), 6
identifying neighbors within autonomous systems, 508
IGP (interior gateway protocol), 292
advertising routes from BGP-4 to IGP, 571-572
advertising routes from IGP to BGP-4, 571
redistributing between BGP-4, 570
IGRP (Interior Gateway Routing Protocol), 178-179
configuring default metrics, 618
convergence, 184
default routes, 624
implementing IP access lists, 44
init state, 223
Integrated IS-IS, 346
adjacencies, 361-362
establishing on broadcast links, 362
establishing on NBMA links, 363
establishing on point-to-point links, 362
area routing, 358-360
Integrated IS-IS 910
configuring, 380-381
decision process, 375-376
design considerations, 377-378
forwarding process, 377
ISO addressing, 354-355
NETs, 356-357
NSAPs, 356
L1 routers, 357
L2 routers, 358
Level 1-2 routers, 358
neighbors, 360
NMBA, configuring, 386-388
packet types, 364-366
LSPs, format, 367-368
NSPs, format, 368-369
receive process, 377
route summarization, 379
routing level, configuring, 381-383
summarization, configuring, 384-386
TLVs, 369-371
troubleshooting, 399-402
update process, 372-374
verifying operation, 389-390
versus OSPF, 350-353
interarea routers, 357
interarea summarization, 300
Interconnecting Cisco Network Devices. See ICND
interdomain routing, 98
interior gateway protocol. See IGP
interior routing protocols, 176
intermittent connectivity, 40
internal BGP-4, 492
internal routers, 291
Internet and IP addresses,, 92-94
fixing problems with CIDR, 99
multiple connections to, 560-562
Internet Assigned Numbers Authority (IANA), 93
Internet Corporation for Assigned Names and Numbers (ICANN), 93
Introduction to Cisco Router Configuration (ICRC), 6
IP access lists, 45. See also access lists alleviating network congestion with Cisco
routers, 43
extended IP access lists, 46, 48
implementing, 44
standard IP access lists, 45-46
uses of, 51
ip access-group command, 45
IP addresses, 91
and the Internet, 99
bit allocation, 94
classes, 93
controlling network traffic, 44, 61-62
host addressing, 92
Internet, 92-94
Internet authoriative bodies, 93
Internet masks, 92
networks, 92
optimizing, 116-118
private addresses, 124-125
subnet masks, 94, 98
logical AND, 95-96
network boundaries, 94
rules, 97
rules for IP subnetting, 96-97
summary of, 130
ip classless command, 632
ip forward-protocol command, 60
IP helper addresses, controlling network traffic, 59-60
IP networks, designing, 118-123
ip ospf cost, 239
ip ospf network, 242
ip ospf network non-broadcast, 244
ip unnumbered command, 113
IP VLSM subnets, assigning to WAN connections, 116-117
IPX (Internetwork Packet Exchange), configuring EIGRP for, 459-461
ISO addressing, 354-355
NETs, 356-357
NSAPs, 356
ISPs, connecting to, 512-513

K-L
keepalives, BGP-4 message types, 492
L1 routers, 347, 357
L1-2 routers, 347
L2 routers, 347, 358
LAN Hello packets, 366
Layer 3 addresses, 89
need for, 88-89
network characteristics of, 90
layers, design rules for, 42
interarea routers 911
Level 1-2 routers, 358
link-state advertisements. See LSAs
link-state routing protocols, 174-175
networks, 175
path selection, 176
updating local network tables, 176
LLQ (low-latency queuing), 55
load balancing EIGRP, 454
RIPv1, 178
loading state, 224
local preference attribute, 502
BGP-4, tuning, 564-565
logical AND, 95-96
Logical Hop field, 166
loopback interfaces, 238
configuring OSPF on internal routers, 237
low-latency queuing (LLQ), 55
LSAs (links-state advertisements), 176
OSPF, 293-294
propagating, 294-295
LSPs (link-state packets), 347

M
maintaining redistribution, 644
topology databases, 227
topology tables, 436
major addresses, 92
managing BGP-4 configurations, 510-511
IP network congestion, 44
manual summarization, 113
match commands, policy routing with route maps, 634, 640-643
match route map command, 634
MED (Multiple Exit Discriminator) attribute, 502
message types, BGP-4, 492
Metric field, 165
metrics default metrics, 617-618
distance vector metrics, 173
EIGRP, 438-439
routing metrics, 608
seed metrics, 617
monitoring policy routing, commands for, 645
multihoming, 560
multiple areas area boundaries, 290
OSPF, 289
design considerations, 299, 302
NBMA, 301
path selection, 295
summarization, 300
virtual links, 300
Multiple Exit Discriminator (MED) attribute, 502
multiple Internet connections, 561-562

N
NAT (Network Address Translation), 125-126
features of, 127-128
NBMA (nonbroadcast multiaccess) configuring bandwith over, 457
OSPF, 231
choosing topologies, 232
Cisco-specific, 231
configuring, 242-243
Frame Relay topologies, 232
in multiple areas, 301
network topologies, 215
RFC-complaint, 231
subinterfaces, 232-233
neighbor command, 244
neighbors, 360
EIGRP, hello protocol, 434-435
identifying autonomous systems, 508
OSPF, 214
adjacent neighbors, 217
designated routers, 218-219, 221
finding with exchange process, 222-223
hello packets, 216-217
Net Flow, 58
NETs (network entity titles), 347, 356-357
network addresses, 92-94
network command, OSPF, 234-237
configuring multiarea networks, 302-303
configuring on internal routers, 235
network congestion, 35. See also networks alleviating withCisco routers, 43
dropped packets, 37
excessive traffic, 36
IP, managing, 44
network design, 35
network congestion 912
retransmission of packets, 37
routing tables, 37
runaway congestion, 39
scaling networks, 41
server lists, 38
Spanning-Tree Protocol, 38-39
symptoms of, 39-40
traffic analysis, 35
Network field, routing tables, 164-165
network summary link, LSAs, 294
network traffic. See also network congestion
networks adding to topology tables, 443
address translation, 125-126
addressing, 89-91
as defined by Layer 3, 89
broadcast multiaccess networks, Next Hop attribute, 505
case studies, 32-33
creating, 40
hierarchical designs, 41
scaling to reduce congestion, 41
defining to be advertised, 508
definitions of, 90
discontiguous, 114
fully meshed networks, BGP-4, 546
hiding changes, summarization, 112
hierarchical designs, 41
Access layer, 42
Core layer, 42
Distribution layer, 42
rules for each layer, 42
IP addresses, 92
IP boundaries, 94
link-state routing protocols, 175
nonbroadcast multiaccess networks, Next Hop attribute, 505
OSPF, 214
broadcast multiaccess, 214
multiple area networks 289
NBMA, 215
poin-to-point, 215
point-to-multipoint, 215
virtual links, 216
redistribution, 613-614
requirements of, 33
accessibility/security, 34
adaptability/serviceability, 34
efficiency, 34
increasing network traffic, 35
reliability, 33
responsiveness, 33
traffic, controlling Cisco express forwarding, 58
design of client/server network, 59
EIGRP, 60
IP helper address, 59
null interfaces, 55-56
placement of clients/servers, 59
silicon switching, 58
tunneling into IP, 61-62
with CPUs, 58
Next Hop attribute (BGP-4), 502-505
Next Logical Hop field, routing tables, 166-167
Next-Hop addresses, forcing, 508
NIC address, 91
no ip address, 245
nonbroadcast multiaccess. See NBMA
no-summary command, 308
not so stubby areas. See NSSAs
notification, BGP-4 message types, 492
NPDUs (network protocol data units), 347
NSAPs (network service access points), 348, 356
NSEL (network selector), 348
NSSAs (not so stubby areas), 298
external LSAs, 294
null interfaces controlling routing updates, 601
internet example, 55
intranet example, 56
reducing network traffic, 55-56

O
OL (Overload) bit, 348
open messages (BGP-4), 492
Open Shortest Path First. See OSPF
optimizing IP address space, 116, 118
options for configuring OSPF on internal routers, 237-240
Origin attribute (BGP-4), 501
Originator ID, 503
OSPF (Open Shortest Path First)), 44, 179
attributes of, 180
case studies, 211
Network field, routing tables 913
checking configurations in multiarea networks show ip ospf border-routers command, 316
show ip ospf virtual-links command, 317-318
checking configurations on a single router, 246
show ip ospf command, 247
show ip ospf database command, 248
show ip ospf interface command, 250, 252
show ip ospf neighbor command, 252, 254
show ip protocols command, 255-256
show ip route command, 257
checking configurations on a single server, show ip ospf database command, 250
checking configurations on multiarea networks, 315
configuring, 234
default metric, 617
in broadcast mode, 244
in NBMA mode, 242-243
in point-to-multipoint mode, 244
in point-to-point mode on a Frame Relay subinterface, 245
on a single router, 240
on internal routers, 234, 238
over NBMA topology, 242
virtual links, 311
convergence, 185
designs, router types, 291
designs within areas, 291
hello protocol, 214
in multiple areas area boundaries, 290
design considerations, 299
NBMA, 301
summarization, 300
virtual links, 300
in single areas, disadvantages of, 290
LSAs, 293-294
multiarea networks, 302
area range command, 304-305
commands for stub areas, 307
network command, 302-303
OSPF command for the cost of default routes propagated to the area, 309
summarization command, 305
totally stubby areas, 308
working configurations, 314
NBMA choosing topologies, 232
Cisco-specific, 231
Frame Relay topologies, 232
RFC-compliant, 231
subinterfaces, 232-233
neighbors, 214
adjacent neighbors, 217
designated routers, 218-219, 221
finding with exchange process, 222-223
hello packets, 216-217
network topologies, 214
broadcast multiaccess, 214
NBMA, 215
point-to-multipoint, 215
point-to-point, 215
virtual links, 216
path selection between areas, 295
calculating cost, 296-297
router types, 291-292
routes, discovering, 224
routing protocol, enabling, 235
routing tables building, 221-222
building routing tables on new OSPF routers, 222
building SPF, 231
choosing SPF, 230
learning new routes, 227-228
maintaining, 227
topology databases, 226
updating topology tables, 226
routing tables codes and associated LSAs, 297
terminology, 212-213
topology databases, maintaining, 227
types of areas, 297-299
versus Integrated IS-IS, 350-353
ospf auto-cost command, 239
ospf neighbor command, 243
Outgoing Interface field, routing tables, 165
overview of IP access lists, 45

P-Q
packets ensuring they are switched at speed, 643
Integrated IS-IS, 364-366
LSPs, format, 367-368
network congestion, 37
retransmitting, 37
NSPs, format, 368-369
packets 914
passive interface command, 622
passive interfaces, 601
redistribution, 621
PAT (port address translation), 127
path selection between routing protocols, 181, 610
calculating cost, 296
link-state routing protocols, 176
OSPF between areas, 295
calculating cost of, 297
routing protocols, administrative distance, 181-183
routing tables, 608-609
within routing protocols, 608
paths, removing from topology tables, 444
peer groups, 508
ping, extended ping, 645
point-to-multipoint OSPF network topologies, point-to-multipoint OSPF topologies, 215
configuring, 244
point-to-point OSPF network topologies, 215
Point-to-point Hello packets, 366
policy routing advantages of, 637-638
BGP-4, 490, 497
attributes, 500-503
disadvantages of, 499
rules of, 497
characteristics of, 637
commands for monitoring, 645
configuring route maps, 640
disadvantages of, 638
route maps, 633, 636-638
match commands, 640-643
port address translation. See PAT
prefix lists, 576-577
BGP-4, 557
configuring, 558
creating, 558
examples of, 559
verifying configurations, 559-560
prefix routing. See CIDR, 98
prerequisites for BSCI course, 5
prioritization, access lists, 54-55
priority, 55
priority command, 240
priority queuing, 54
private addresses, 124-125
problems with IP addressing and the Internet, 99
with OSPF in a single area, 290
with redistribution and network convergence, 613
process ID, 235
processing prefix lists, 558
professional-level certifications, 3
propagating LSAs, 294-295
proprietary Cisco solutions for alleviating network congestion, 44
protocols definition of, 163
distance vector protocols. See distance vector
protocols IGP, 292
link-state routing protocols. See link-state
routing protocols routing protocol. See routing protocols
pseudonodes, 349
PSNP (partial sequence number packet), 348
purpose of routing protocols, 163

R
reasons for controlling routing updates, 602-603
receive process (Integrated IS-IS), 377
redistribute command, 617
redistribute connected subnets, 236
redistribution, 181, 599
administrative distance, configuring, 619-620
avoiding routing loops, 612
between IGP and BGP-4, 570
between routing protocols, 599, 601
case studies, 599
configuring, 615
configuration syntax, 615-616
default metrics, 617
configuring multiple routing protocols, 607
controlling routing updates, 601
controlling routing updates with filtering, 625
default metrics, 617
default routes, 623-624
examples of, 627-633
features of, 604
default redistribution between routing protocols, 604-606
multiple protocols, 606-607
passive interface command 915
network convergence, 613-614
passive interfaces, 621
path selection between routing protocols, 608-610
reasons for using on routing protocol, 607
routing updates, controlling, 602
seed metrics, 617
static routes, 621-623
verifying, 644
extended ping, 645
traceroute, 644
reducing network traffic, 55-56
size of routing tables, 112
reliability, network requirements, 33
remote networks, finding alternative paths to, 446, 449
removing paths or routers from topology tables, 444
requirements of networks, 33-34
accessibility/security, 34
efficiency, 34
increasing network traffic, 35
reliability, 33
responsiveness, 33
responsiveness, requirements of networks, 33
RFC-compliant NBMA, 231
RIPv1 (Routing Information Protocol version 1), 177-178
configuring default metrics, 617
convergence, 183
route aggregation, BGP-4, 496-497
route map command syntax, 635
route maps BGP-4, 557
characteristics of, 634-635
controlling routing updates, 602
policy routing, 633-638
match commands, 640-643
statements, 639
uses for, 634
route reflectors, 575-576
characteristics of, 549-550
fully meshed IBGP-4 networks, 547-548
rules for propagating updates, 550-556
route selection, BGP-4, 505-507
route summarization, Integrated IS-IS, 379
route switching, 643
routed protocols versus routing protocols, 163-164
route-map command, 635
router ID, 235
configuring, 237-238
router link LSAs, 293
router ospf process number command, 235
routers. See Cisco routers designated routers, OSPF, 218-221, 291-292
removing from topology tables, 444
routes autonomous systems, aggregating, 509
OSPF, discovering, 224, 226
routing policy-based routing. See policy routing
SIN routing, 604
versus switching, 169
Routing and Switching career tracks, 7
Routing Domains, 349
BSCI exam, 3-4
contents of, 9-12
routing function, 169
Routing Information Protocol version 1. See RIPv1
routing loops, 173, 612-614
routing metrics, 608
routing protocols case studies, 162
definition of, 163
exterior routing protocols, 176
IGRP, 178-179
interior routing protocols, 176
link-state routing protocols. See link-state protocols
OSPF, 179
attributes of, 180
enabling, 235
path selection, 181, 608-610
administrative distance, 181-183
purpose of, 163
redistribution, 599-601
RIPv1, 177-178
types of, 171
classful routing protocols, 171
classless routing protocols, 171-172
versus routed protocols, 163-164
VLSM, 103-104
routing tables keeping current and correct, 168-169
Metric field, 165
network congestion, 37
routing tables 916
Network field, 164-165
Next Logical Hop field, 166-167
OSPF building, 221-222
building routing tables on new OSPF routers, 222
building SPF, 231
choosing SPF, 230
learning new routes, 227-228
maintaining, 227
topology databases, 226
updating topology tables, 226
Outgoing Interface field, 165
path selection, 608-609
reducing size of, summarization, 112
updating in active mode with DUAL, 442-449
routing updates, controlling, 52-54, 602
reasons for , 602-603
redistribution, 601
with filtering, 626-627
routing/switching relationships in Cisco routers, 170-171
rules for propagating updates, 550-556
for VLSM, 132
IP addresses, subnets, 97
of policy routing, 497
of VLSM, 104
runaway congestion, 37-39

S
scaling EIGRP, 449-451
networks, 41
scenario 11-1, 667
answers to, 671-673
scenario 11-2, 668-669
answers to, 673-674
scenario 11-3, 669-670
answers to, 675-677
scenario 11-4
part A, 678-682
answers to, 683-686
part B, 687
answers to, 688-689
part C, 689-704, 706-709, 711-714, 716-720
answers, 720-724
scenario 11-5, 724
part A, 726
answers, 726-728
part B, 728
answers, 728-731
part C, 731, 733-765
answers, 765-769
security, access lists, 51-52
seed metrics, 617
server lists, network congestion, 38
servers, placement of in controlling network traffic, 59
serviceability, network requirements, 34
set command, 638
set route map command, 634
ships in the night (SIN) routing, 604
shortest path first. See SPF
show buffers, 35
show clns interface command, 393-395
show clns neighbors command, 391-393
show cpu process command, 291
show interface command, 35, 457
show ip bgp command, 510, 567
show ip bgp neighbors command, 510
show ip bgp paths command, 510
show ip bgp summary command, 510
show ip eigrp neighbors command, 462
show ip eigrp topology command, 462-464
show ip eigrp topology all command, 462
show ip eigrp traffic command, 462-464
show ip ospf command, 246
show ip ospf border-routers command, 315-317
show ip ospf command, 247-248
show ip ospf database command, 246-250
show ip ospf interface command, 246, 250-252
show ip ospf neighbor command, 222, 246, 252-254
show ip ospf virtual links command, 315-318
show ip prefix-list command, 559-560
show ip protocols command, 246, 255-256
show ip route command, 167-168, 246, 257
show ip route eigrp command, 465
show ipx route command, 462
show isis database command, 396-397
show isis database detail command, 397-399
show isis spf-log command, 400-401
show memory command, 291
show queuing command, 35
silicon switching command, 58, 171
SIN (ships in the night) routing, 604
routing updates, controlling 917
SNP (Sequence number PDU), 349
SNPA (subnetwork point of attachment), 350
Spanning-Tree Protocol, network congestion, 38-39
SPF (shortest path first), 226
building routing tables, 230-231
split horizon rule, 173, 177
split horizon with poison reverse, 177
starting routing processes, autonomous systems, 508
statements, route maps, 639
static addressing, NAT, 127
static routes, 164, 601
redistribution, 621-624
VLSM, 104
stop telnet, 48
strategies for exam day, 21-22
stub area, 298
OSPF commands, 307-308
study strategies, 17-19
sub net zero, 107
subinterfaces, OSPF configuring in point-to-point mode, 245
NBMA, 232-233
subnet masks IP addresses, 94, 98
logical AND, 95-96
network boundaries, 94
rules, 97
subnetting, 96
VLSM. See VLSM
subnet rules, 97, 107
subnetwork dependent layer, 349
subnetwork independent layer, 350
successors, choosing, 442-443
summarization, 109
address exhaustion, 113
advantages of, 112, 132
alternatives to, 115
automatic summarization, 113
discontiguous networks, 114-115
EIGRP, 454, 727
IP address space, optimizing, 116-118
manual summarization, 113
OSPF in multiple areas, 300
summarization command, 305
summary-only command, 509
supernet addresses, 92
supernets, 109
switching versus routing, 169
switching function, 170
symptoms of network congestion, 39-40
synchronization autonomous systems, disabling, 509
BGP-4, 494
syntax of route map command, 635

T
terminal access, controlling, 51-52
terminology of EIGRP, 432-433
TLV (Type/Length/Value), 350, 369-371
topologies, OSPF NBMA, 232
topology tables, 435
adding to networks, 443
EIGRP, hello protocol, 436, 438
maintaining, 227, 436
OSPF, routing tables, 226
removing paths or routers, 444
totally stubby areas, OSPF commands, 308-309
traceroute command, verifying redistribution, 644
traffic controlling in BGP-4, 556
network congestion, 36
route switching, 643
traffic analysis, network congestion, 35
traffic control, routing updates, 52, 54
translating addresses, 125-126
triggered update RIPv1, 177
with poison reverse, 183
troubleshooting Integrated IS-IS, 399-402
redistribution, 644
tunnel interface, 63
tunneling into IP, controlling network traffic, 61-62
two-way state, 223
types of OSPF areas, 297, 299
of routing protocols classful routing protocols, 171
classless routing protocols, 171-172
types 918

U
underruns, 702
update messages, BGP-4 message types, 492
update process (Integrated IS-IS), 372-374
updates, rules for propagating, 550, 552-554, 556
updating local network tables, link-state routing protocols, 176
routing tables, 168-169
in active mode with DUAL, 441-449
in passive mode with DUAL, 440

V
variable-length subnet masks. See VLSM
variance command, 454-456
verifying BGP-4 attribute configurations, 510-511, 567-570
EIGRP operations, 462
debug commands, 465
show ip eigrp neighbors, 462
show ip eigrp topology, 463
show ip eigrp traffic, 464
filter configuration, 49
Integrated IS-IS operation, 389-390
prefix lists configurations, 559-560
redistribution, 644
extended ping, 645
traceroute, 644
virtual links (OSPF) configuring, 312
in multiarea networks, 300, 311
network topologies, 216
virtual terminal line, 51
VLANs, 89
VLSMs (variable-length subnet masks), 103
address allocation, 107
advantages of, 104
allocating VLSM addresses, 107
bit allocation, 107
case studies, 105-107
example of, 103
routing protocols, 103
rules for, 132
rules of, 104
static routes, 104
vty (virtual terminal line), 51-52

W-Z
WANs
assigning IP VLSM subnets, 116-117
bandwith command and EIGRP, 457
Weight attribute (BGP-4), 503, 564
writing access lists, guidelines for, 48-49
underruns