Table of Contents


Index

Symbols

56 Kbps, ISP prices, 40

A

addresses
hosts
global, 76
private, 76
local-use, IP addresses depletion, 81-82
multihoming
different providers, 72-73
single provider, 70-71
single-homing
outside provider's space, 70
unicast, IP addresses depletion, 79-80
Acceptable Use Policy (AUP), 4
advertise maps, 363
aggregate masks, 64-66
aggregation
BGP4, 180-183, 342
AS-SET, 184-186, 356-359
attributes, 185-186
attributes, changing, 360-362
forming based on subset of specific routes, 363-365
information loss, 184, 356-359
more specific routes, 346-351
specific routes, 343-346
subset of more specific routes, 352-356
black holes (routing), 70, 72
domains, 74
routes, 157-159
AGGREGATOR attribute (BGP), 166, 167
allocation (IP addresses), 61
Ameritech (NAPs), 9
ANS (Advanced Network and Services), 4
NOC (Network Operating Center), 4
Routing Registry, 31
APNIC (Internet Registry), 30
ARPA (Advanced Research Projects Agency), 3
DARPA, 3
ARPANET, 4
AS macros (RIPE), 448-449
AS object (RIPE), 444-445
policies, 449-452
based on routes, 452-454
AS-SET, BGP4 aggregation, 184-186, 356-359
AS_path (BGP)
attribute, 154-155, 331-333
manipulation, 159-160
load balancing, 227-228
AS_path (BGP), Continued
redundancy, 227-228
symmetry, 227-228
routes
complex regular expressions, 176-178
filtering, 310-311
identifying (BGP), 174
multiple-character patterns, 176
regular expressions, 174
single-character patterns, 175-176
routing, 398-399
Asian ISPs, 5
ASs (Autonomous Systems)
AS_path approach, 398-399
BGP (Border Gateway Protocol)
policies, 242-243
route reflectors, 253-263
BGP peer sessions
continuity, 129
synchronization, 130-132
community approach, 395-398
confederations, 263-266
centralizing, 266
route reflectors, 267
defaults, 399-402
confederations, 427-432
EIGRP as IGP, 411-413
IGRP as IGP, 414-416
ISIS as IGP, 416-418
loops, 402-404
OSPF, 405-409
policy routing, 418-422
RIP as IGP, 409-411
route reflectors, 422-427
IRR (Internetworking Routing Registries), 30-31
private numbers, 333-335
BGP, 155-157
route dampening, 291-293
routers
BGP, 234-235
IBGP, 235
non-BGP, 235
routing policy, 244-248
ATM (Asynchronous Transfer Mode), 18
ATOMIC_ AGGREGATE attribute (BGP), 165-166
attributes
BGP, 147, 326
AGGREGATOR, 166-167
AS_path, 154-155, 331-333
AS_path manipulation, 159-160
ATOMIC_AGGREGATE, 165-166
changing, 172
community, 164-165, 340-342
local preference, 161-162, 335-337
MULTI_EXIT_DISC (MED), 162-164
Multi_Exit_Disc (MED), 337-339
NEXT_HOP, 148-154, 330-331
ORIGIN, 167
private AS numbers, 333-335
RTA configuration, 327
RTC configuration, 328-329
RTD configuration, 329
RTF configuration, 327-328
BGP4, 116-118
aggregation, 185-186, 360-362
routes, 306
AUP (Acceptable Use Policy), 4
authenticating BGP peer sessions, 129
automatic load balancing, 211
BGP defaults, 382-385
between routers, 385-387
Autonomous System numbers (InterNIC templates), 25
autonomous systems (AS), 95-96
multihomed nontransit, 98-99
multihomed transit, 100-101
stub, 97-98
see also, ASs (Autonomous Systems)

B

Backbone Network Service (vBNS), 8
backbones
ISPs, 41
bottlenecks, 42
distance to destinations, 44
hops, 44
oversubscribing, 42
physical connection, 41
redundancy, 43
traffic exchange agreements, 44
NSFNET, 7
regional networks, transitioning, 19-20
vBNS (Very High-Speed Backbone Network Service), 17
backdoors, 324-326
protocols, 140-141
backup link overloads (route instabilities), 287
backups (private links)
different providers, 394-395
same providers, 391-394
basic addressing (IP), 54
class A, 54
class B, 55
class C, 55
subnetting, 55-57
BGP (Border Gateway Protocols), 125
AS_path
complex regular expressions, 176-178
multiple-character patterns, 176
regular expressions, 174
single-character patterns, 175-176
ASs (Autonomous Systems)
internal default (avoiding loops), 402-404
policies, 242-243
private numbers, 155-157
route reflectors, 253-263
attributes, 147, 326
AGGREGATOR, 166-167
AS_path, 154-155, 331-333
AS_path manipulation, 159-160
ATOMIC_AGGREGATE, 165-166
changing, 172
community, 164-165, 340-342
local preference, 161-162, 335-337
MULTI_EXIT_DISC (MED), 162-164, 337-339
NEXT_HOP, 148-154, 330-331
ORIGIN, 167
private AS numbers, 333-335
RTA configuration, 327
RTC configuration, 328-329
RTD configuration, 329
RTF configuration, 327-328
backdoor protocols, 140-141
defaults
AS-path, 398
automatic load balancing, 382-385
community approach, 395
dynamically learned, 368-369
load balancing between routers, 385-387
multihomed to different providers, 387-391
statically set, 370-373
external, 126
filtering routes, 169
inbound, 169-170
outbound, 169-170
injecting routes
dynamically, 133
faulty information, 134
route fluctuation, 135-137
internal, 126
load balancing, 193, 201-203
AS_path, 227-228
automatic, 211
multihomed, 209
multihomed to different provider, 215-219
multihomed to single provider, 205-214
multiple providers, 223-228
private links, 219-223
single-homed, 204-205
traffic, 202
model, 142
decision process, 143-144
decision process summary, 168-169
Input Policy Engine, 143
Output Policy Engine, 144
sample routing environment, 145-147
peer groups, 178-179, 312-315
exceptions, 180
update policies, 312
peer sessions, 125, 300
AS continuity, 129
AS synchronization, 130-132
authenticating, 129
IP addresses, 128-129
logical, 127
loopback interface, 128
physical connections, 127
race condition, 127
RTA configuration, 301-303
RTC configuration, 304
RTD configuration, 304-305
RTF configuration, 303- 305
redundancy, 193, 203
AS_path, 227-228
default routes, 195-196
dynamic routes, 196-197
geographical issues, 194-195
multihomed, 209
multihomed to different provider, 215-219
multihomed to single provider, 205-214
multiple providers, 223-228
private links, 219-223
redundancy, Continued
single-homed, 204-205
statically set routes, 197-200
route instabilities, 288
route and cache invalidation, 288-289
route dampening, 289-290
routers, 233
ASs, 234-235
defaults, 238-239
IGP metric, 237
injecting into IGP, 234
OSPF-generated defaults, 240-241
Primary/Backup policy, 236-237
RIP-generated defaults, 239
shorter paths than IGP, 238
transit routers, 238
routes
aggregations, 157-159
AS_path, 174
injecting, 132-137
injecting dynamically, 315-322
injecting statically, 323
NLRI, 172-174
ORIGIN, 137-139
route maps, 306-308
routing, static versus dynamic, 139
soft reconfiguration, 433-437
symmetry, 193, 201-203
AS_path, 227-228
multihomed, 209
multihomed to different provider, 215-219
multihomed to single provider, 205-214
multiple providers, 223-228
private links, 219-223
single-homed, 204-205
BGP4, 101-102
aggregation, 180-183, 342
AS-SET, 184-186, 356-359
attributes, 185-186
attributes, changing, 360-362
forming based on subset of specific routes, 363-365
information loss, 184, 356-359
more specific routes, 346-351
specific routes, 343-346
subset of more specific routes, 352-356
attributes, 116-118
CIDR (Classless Interdomain Routing), 114
KEEPALIVE messages, 104
message header format, 104-106
neighbor negotiation, 103, 106
finite state machine (FSM), 108-111
KEEPALIVE message, 112-113
NOTIFICATION message, 111-112
OPEN message, 106-108
routing information, 113-114
UPDATE message, 113
Network Layer Reachability Information (NLRI), 114-115
path attributes, 116-118
path vectors, 102
updates, 103
withdrawn routes, 115-116
black holes (routing), 69
aggregating, 70-72
Border Gateway Protocol Version 4, see BGP4
border routers, 100
bottlenecks (ISP backbones), 42

C

CA*net (Routing Registry), 31
cache invalidation (BGP), 288-289
soft reconfiguration, 433-437
centralizing confederations, 266
CIDR (Classless Interdomain Routing)
BGP4, 114
blocks (InterNIC), 24
classless, 65
IP addresses depletion, 60-64
CIX (Commercial Internet eXchange), 5
NAPs, 12
class A (IP addresses), 54
class B (IP addresses), 55
Classless Interdomain Routing, see CIDR
class C (IP addresses), 55
classless routing domains, 65
clients, route reflectors, 256-257
CLNP (Connectionless Networking Protocol), 9
clusters (route reflectors), 256-259
collocation (ISP equipment), 46-47
com (domain name), 26
commands
network, 321-323
redistribute, 317-318
route dampening, 437-442
community attribute (BGP), 164-165, 340-342
community objects (RIPE), 446-448
complex regular expressions (BGP), 176-178
concentration routers, 254
confederations
ASs, 263-266
centralizing, 266
defaults, 427-432
route reflectors, 267
IGP expansion, 274
configurations (NAPs), 10
connections
ISP backbones, 41
logical connections (BGP peer sessions), 127
physical connections (BGP peer sessions), 127
contact registration templates (InterNIC), 24
convergence (routing), 92
count to infinity restrictions (distance vector protocols), 92
CPE (Customer Premises Equipment)
ISPs, 45-46
prices, 41
CPU power (route instabilities), 285
Customer Premises Equipment (CPE), 41, 45-46

D

dampening (routes), 136, 289-290
commmands, 437-442
DARPA, 3
databases
InterNIC, 27-28
IRR (Internetworking Routing Registries), 31
RIPE, 460-461
Routing Arbiter Database (Routing Registry), 31
decision process (BGP), 143-144
summary, 168-169
decommissioning NSFNET, 6
default routes, 95-96
redundancy (BGP), 195-196
defaults
ASs (Autonomous Systems), 399-402
confederations, 427-432
EIGRP as IGP, 411-413
IGRP as IGP, 414-416
ISISas IGP, 416-418
loops, 402-404
OSPF, 405-409
policy routing, 418-422
RIP as IGP, 409-411
route reflectors, 422-427
BGP
AS-path, 398
automatic load balancing, 382-385
community approach, 395
dynamically learned, 368-369
load balancing between routers, 385-387
multihomed to different providers, 387-391
statically set, 370-373
multihomed single providers
default, one primary, one backup, partial routing, 376-382
default only, one primary, one backup, 373-376
demarcation points (DP), 44-45
denying routes, 171
depletion of IP addresses, 53, 60
allocation, 61
CIDR (Classless Interdomain Routing), 60, 62-65
global connectivity, 75
IANA (Internet Assigned Numbers Authority), 61
IP version 6 (IPv6), 78-79
local-use addresses, 81-82
NAT (Network Address Translation), 75-77
private connectivity, 75
provider-based unicast addresses, 79-80
ROAD (Routing and Addressing), 60
DHCP (Dynamic Host Configuration Protocol), 76
dialup asynchronous service (ISP prices), 40
dialup connections (policy routing), 247
dialup services (ISPs), 38
directory services (InterNIC), 27-28
distance to destinations (ISP backbones), 44
distance vector protocols, 92-93
DMZ (NEXT_HOP attribute), 153-154
domain names, 26-27
InterNIC templates, 26
domains (aggregation), 74
DP (demarcation points), 44-45
drawbacks to policy routing, 247-248
dynamic defaults (BGP redundancy), 196-197
Dynamic Host Configuration Protocol (DHCP), 76
dynamic routing, 95-96
versus static, 139
dynamically injecting routes (BGP), 133-137, 315-322
dynamically learned defaults (BGP), 368-369

E

edu (domain name), 26-27
EGBP (External Border Gateway Protocol), 127
IGP expansion, 271-272
EIGRP (IGP, using as), 411-413
equipment
collocation, 46-47
CPE (Customer Premises Equipment), 41, 45-46
European ISPs, 5
exceptions (BGP peer groups), 180
expansion (IGP), 267-269
confederation, 274
EBGP, 271-272
IBGP, 269-271
private AS numbers, 273
external BGP, 126

F

faulty information (injecting routes BGP), 134
FDDI/ATM switches (NAPs), 10
filtering routes, 306
AS_path, 310-311
BGP, 169
inbound, 169-170
outbound, 169-170
NLRI, 308-310
finite state machine (FSM), 108-111
firewalls (policy routing), 246
FIX (Federal Internet eXchange), 5
NAPs, 10-11
flapping (routes), 283
flip-flopping neighbor routers, 109
frame relay (ISPs), 38
full routing, 204
fully meshed topologies, 152

G

geographical components (vBNS), 18
geographical issues of redundancy (BGP), 194-195
global connectivity (IP addresses depletion), 75
Gopher, Registration Service (RS), 24
gov (domain name), 26-27

H

hardware, route instabilities, 285
hops
distance vector protocols, 92
ISP backbones, 44
NEXT_HOP attribute (BGP), 148-149, 330-331
DMZ, 153-154
multiaccess media, 150-151
nonbroadcast multiaccess media, 152
host registration (InterNIC templates), 25
hosts
global addresses, 76
private addresses, 76
HPCC (High Performance Computing and Communication), 7
hubs, route reflectors, 258
human error, route instabilities, 287

I

IANA (Internet Assigned Numbers Authority), 23
IP addresses depletion, 61
IBGP (Interior Border Gateway Protocol)
confederations, 263-266
centralizing, 266
route reflectors, 267
ICM (International Connections Manager), 5
identifying routes (BGP), 171
AS_path, 174
NLRI, 172-173
identifying routes (BGP, based on NLRI), 174
IGP (Interior Gateway Protocol), 126
BGP routers
defaults, 238-239
IGP metric, 237
shorter paths, 238
transit routers, 238
EIGRP (using as IGP), 411-413
expansion, 267-269
confederation, 274
EBGP, 271-272
IBGP, 269-271
private AS numbers, 273
route reflectors, 259-260
routers (ASs), 235
IGRP (using as IGP), 414-416
ISIS (using as IGP), 416-418
RIP (using as IGP), 409-411
routers, injecting BGP into, 234
route instabilities, 284
IGRP (IGP, using as), 414-416
IN-ADDR domain (InterNIC templates), 26
inbound filtering routes (BGP), 169-170
information loss
BGP4, 356-359
BGP4 aggregation, 184
infrastructure (NAPs), 11
injecting routes
BGP, 132-134
dynamically, 133-137
faulty information, 134
into IGP routers, 234
route fluctuation, 135-137
dynamically, 315-322
statically, 323
Input Policy Engine (BGP), 143
internal BGP, 126
internal peers
route reflectors
with, 255-256
without, 254
Internet Registries
APNIC, 30
InterNIC, 22, 29
RIPE NCC, 29
Internet Registry (IR), 23
InterNetworking Routing Registries (IRR), 30-31
InterNIC, 22
ASs (private numbers), 155-157
database services, 27-28
directory services, 27-28
Registration Service (RS), 23
Gopher, 24
POCs (Point of Contacts), 24
templates, 24
WAIS (Wide Area Information Server), 24
WHOIS, 24
Registration Services (RS)
IANA (Internet Assigned Numbers Authority), 23
Internet Registry (IR), 23
support services, 28-29
templates
Autonomous System numbers, 25
CIDR blocks, 24
contact registration, 24
domain names, 26
host registration, 25
IN-ADDR domain, 26
IP numbers, 25
WHOIS, 27, 28
IP protocol (NAPs), 9
IP addresses
allocation, 61
basic addressing, 54
class A, 54
class B, 55
class C, 55
subnetting, 55-57
BGP peer sessions, 128-129
depletion, 53, 60
allocation, 61
CIDR (Classless Interdomain Routing), 60, 62-65
global connectivity, 75
IANA (Internet Assigned Numbers Authority), 61
IP version 6 (IPv6), 78-79
local-use addresses, 81-82
NAT (Network Address Translation), 75-77
private connectivity, 75
provider-based unicast addresses, 79-80
ROAD (Routing and Addressing), 60
IP numbers (InterNIC templates), 25
IP version 6 (IPv6), 78-79
IRC (interregional connectivity), 8
IRR (Internetworking Routing Registries), 30-31
ASs (Autonomous Systems), 30-31
databases, 31
ISDN (ISP prices), 40
ISIS (IGP, using as), 416-418
ISPs (Internet Service Providers), 5, 37-38
Asian, 5
backbones, 41
bottlenecks, 42
distance to destinations, 44
hops, 44
oversubscribing, 42
physical connection, 41
redundancy, 43
traffice exchange agreements, 44
collocation, 46-47
CPE (Customer Premises Equipment), 41, 45-46
demarcation points (DP), 44-45
dialup services, 38
European, 5
frame relay, 38
leased lines, 38
multihoming
different providers, 72-73
single provider, 70-71
multiple
load balancing, 223-228
redundancy, 223-228
symmetry, 223-228
network information services, 22
POP (point of presence), 6
prices, 39-41
regional networks, 21
security, 39
services, 39
single-homing, addresses outside provider's space, 70
IXC (Inter eXchange Carriers), 10

J-K

JPRR (Routing Registry), 31
KEEPALIVE message (BGP4), 104
neighbor negotiation, 112-113

L

LATA (Local Access and Transport), 10
leaf networks, 65
leased lines (ISPs), 38
less specific routes, 68
link state protocols, 93-94
load balancing
BGP, 193, 201-203
AS_path, 227-228
automatic, 211
multihomed, 209
multihomed to different provider, 215-219
multihomed to single provider, 205-214
multiple providers, 223-228
private links, 219-223
single-homed, 204-205
traffic, 202
BGP defaults
automatic, 382-385
between routers, 385-387
local preference attribute (BGP), 161-162, 335-337
local-use addresses (IP addresses depletion), 81-82
logical connections (BGP peer sessions), 127
longest match routing, 67
loopback interfaces (BGP peer sessions), 128
loops
ASs, 402-404
defaults, 238-239
IGP metric, 237
OSPF-generated defaults, 241
Primary/Backup policy, 236
RIP-generated defaults, 239
route reflectors, 261-263
routing, 68
shorter paths than IGP (BGP), 238
transit routers, 238

M

macros (AS for RIPE), 448-449
maintainer object (RIPE), 444
managers (NAPs), 9-10
masks
natural, 56-57
aggregate, 64-66
supernet, 64
networks, 56-57
subnet (VLSM), 56-57
Variable Length Subnet Masks (VLSM), 57-58
routing protocols, 59
MCI (Routing Registry), 31
MED (Multi_Exit_Disc), 162-164, 337-339
attribute (BGP), 337-339
memory (route instabilities), 286
meshed topologies, 152
message header format (BGP4), 104-106
MFS Datanet (NAPs), 9
MILNET, 3
MINET, 3
mobile networks, 139
models (BGP), 142
decision process, 143-144
decision process summary, 168-169
Input Policy Engine, 143
Output Policy Engine, 144
sample routing environment, 145-147
multi-character patterns (AS_path), 176
MULTI_EXIT_DISC (MED) attribute (BGP), 162-164
attribute (BGP), 337-339
multiaccess media, NEXT_HOP attribute, 150-151
nonbroadcast, 152
multihomed, 67
different providers, 72-73, 387-391
load balancing, 209
redundancy, 209
different providers, 215-219
single provider, 205-214
single provider, 70-71, 373
default, one primary, one backup, partial routing, 376-382
default only, one primary, one backup, 373-376
symmetry, 209
different providers, 215-219
single provider, 205,-214
multihomed nontransit AS, 98-99
multihomed transit AS, 100-101
multiple providers
load balancing, 223-228
redundancy, 223-228
symmetry, 223-228
mutual redistribution (injecting routes BGP), 134

N

NAPs (Network Access Points), 7-9
Ameritech, 9
CIX (Commercial Internet eXchange), 12
CLNP (Connectionless Networking Protocol), 9
configurations, 10
FDDI/ATM switches, 10
FIX (Federal Internet eXchange), 10-11
infrastructure (physical), 11
IP (Internet Protocol), 9
IXC (Inter eXchange Carriers), 10
LATA (Local Access and Transport), 10
managers, 9-10
MFS Datanet, 9
PacBell, 9
regional networks, 20
Route Arbiter (RA) project, 13-15
network management system, 15
route server, 15
Routing Arbiter Database (RADB), 16
routing engineering team, 16
route servers, 13-15
routing, 13
speeds, 9
Sprint, 9
transitioning from NSFNET, 10
vBNS, 18
NAT (Network Address Translation), 75-77
IP addresses depletion, 75-77
natural masks, 56-57
aggregate, 64-66
supernet, 64
neighbor negotiation (BGP4), 106
finite state machine (FSM), 108-111
KEEPALIVE message, 112-113
NOTIFICATION message, 111-112
OPEN message, 106-108
routing information, 113-114
UPDATE message, 113
neighbors routers
BGP4, 103
flip-flopping, 109
net (domain name), 26
network command, 321-323
network information services, 22
Network Layer Reachability Information (NLRI), 114-115
BGP, 174
filtering, 308-310
identifying (BGP), 172-173
network management system, Route Arbiter (RA) project, 15
networks
ARPANET, 4
CIX Commercial Internet eXchange), 5
FIX (Federal Internet eXchange), 5
ICM (International Connections Manager), 5
leaf, 65
masks, 56-57
naturals, 56-57
MILNET, 3
MINET, 3
mobile, 139
NIS managers, 20-21
NREN (National Research and Education Network), 7
NSFNET, 4
backbone, 7
Backbone Network Service (vBNS), 8
decommissioning, 6
HPCC (High Performance Computing and Communication, 7
IRC (interregional connectivity), 8
NAPs (Network Access Points), 7
RAs (Route Arbiters), 7
NSP (Network Service Provider), 7
regional
NAPs, 20
new Internet providers, 21
transitioning, 19-20
upgrades, route instability, 286-287
Virtual Private Networks (VPN) route reflectors, 275-277
NEXT_HOP attribute (BGP), 148-149, 330-331
DMZ, 153-154
multiaccess media, 150-151
nonbroadcast multiaccess media, 152
NIS managers, 20-21
InterNIC, 22
Registration Service (RS), 23
NLRI (Network Layer Reachability Information)
BGP, 174
filtering, 308-310
identifying (BGP), 172-173
NOC (Network Operating Center), 4
non-BGP routers, 233
ASs, 235
non-clients (route reflectors), 256-257
nonbroadcast multiaccess media
NEXT_HOP attribute, 152
NOTIFICATION message (BGP4), 111-112
NREN (National Research and Education Network), 7, 21
Presidential budget (1992), 22
NSFNET
backbone, 7
Backbone Network Service (vBNS), 8
decommissioning, 6
HPCC (High Performance Computing and Communication), 7
InterNIC, 22
Registration Service (RS), 23
IRC (interregional connectivity), 8
NAPs, 8-9
Ameritech, 9
MFS Datanet, 9
PacBell, 9
speeds, 9
Sprint, 9
transitioning from, 10
NAPs (Network Access Points), 7
network information services, 22
NIS managers, 20-21
NREN (National Research and Education Network), 21
RAs (Route Arbiters), 7
NSP (Network Service Provider), 7

O

objects (RIPE), 443
AS, 444-445
policies, 449-452
policies based on routes, 452-454
community, 446-448
maintainer, 444
route, 445-446
OPEN message (BGP4 neighbor negotiation), 106-108
org (domain name), 26
ORIGIN attribute (BGP), 167
routes, 137-139
OSPF, ASs (default), 405-409
OSPF-generated defaults, 240-241
outbound filtering (routes), 169-170
Output Policy Engine (BGP), 144
overlapping protocols, 324-326
oversubscribing (ISP backbones), 42

P

PacBell (NAPs), 9
partial routing, 204
path attributes (BGP4), 116-118
path vectors (BGP4), 102
peer groups
BGP, 178-179, 312-315
exceptions, 180
update policies, 312
route reflectors, 422-427
peer routers (BGP4), 103
peer sessions (BGP), 125, 300
AS continuity, 129
AS synchronization, 130-132
authenticating, 129
IP addresses, 128-129
logical, 127
loopback interface, 128
physical connections, 127
race condition, 127
RTA configuration, 301-303
RTC configuration, 304
RTD configuration, 304-305
RTF configuration, 303-305
peers (route reflectors)
with, 255-256
without, 254
permitting routes, 171
physical connections (BGP peer sessions), 127
physical infrastructure (NAPs), 11
pit buckets (routing), 68
POCs (Point of Contacts), 24
policies
AS object (RIPE), 449-452
based on routes, 452-454
ASs (BGP), 242-243
policy routing, 244-245
ASs defaults, 418-422
dialup connections, 247
drawbacks, 247-248
firewalls, 246
POP (point of presence), 6
Presidential budget (1992), NREN (National Research and Education Network), 22
prices (ISPs), 39-40
CPE (Customer Premised Equipment), 41
Primary/Backup policy, 236-237
private AS numbers
BGP, 333-335
IGP expansion, 273
private connectivity, IP addresses depletion, 75
private links
backups
different providers, 394-395
same providers, 391-394
load balancing, 219-223
redundancy, 219-223
symmetry, 219-223
private numbers (ASs), 155-157
protocols
backdoor, 140-141
distance vector protocols, 92-93
Dynamic Host Configuration Protocol (DHCP), 76
link state protocols, 93-94
overlapping, 324-326
routing (VLSM), 59
provider-based unicast addresses, 79-80
providers
AS_path approach, 398-399
community approach, 395-398
multihomed to different, 387-391
private links
backups, different providers, 394-395
backups, same providers, 391-394
purely dynamic (injecting routes BGP), 133-137

R

race condition (BGP peer sessions), 127
RADB (Routing Engineering Team), 16
RAs (Route Arbiters), 7
redistribute command, 317-318
redundancy
BGP, 193, 203
AS_path, 227-228
default routes, 195-196
dynamic defaults, 196-197
geographical issues, 194-195
multihomed, 209
multihomed to different providers, 215-219
multihomed to single provider, 205-214
multiple providers, 223-228
private links, 219-223
single-homed, 204-205
statically set routes, 197-200
redundancy, Continued
ISP backbones, 43
route reflectors, 257
regional networks
NAPs, 20
new Internet providers, 21
transitioning, 19-20
Registration Service (RS)
Gopher, 24
IANA (Internet Assigned Numbers Authority), 23
Internet Registry (IR), 23
InterNIC, 23
POCs (Point of Contacts), 24
templates, 24
WAIS (Wide Area Information Server), 24
WHOIS, 24
regular expressions (AS_path), 174
complex, 176-178
RIP
IGP, using as, 409-411
RIP-generated defaults, 239
RIPE, 443
AS macros, 448-449
database, 460-461
multi-AS example, 454-460
objects, 443
AS, 444-454
community, 446-448
maintainer, 444
route, 445-446
RIPE (Routing Registry), 31
RIPE NCC (Internet Registry), 29
ROAD (Routing and Addressing), 60
Route Arbiter (RA) project, 13-15
network management system, 15
route server, 15
Routing Arbiter Database (RADB), 16
routing engineering team, 16
route dampening
ASs, 291-293
commmands, 437-442
route invalidation (BGP), 288-289
route maps
advertise maps, 363
BGP, 306-308
route object (RIPE), 445-446
route reflectors
BGP, 253-254
clients, 256-257
clusters, 256-259
confederations, 267
hubs, 258
IBGP, 259-260
loops, 261-263
non-clients, 256-257
peer groups, 422-427
peers
with, 255-256
without, 254
redundancy, 257
Virtual Private Networks (VPN), 275-277
route server, Route Arbiter (RA) project, 15
route servers (NAPs), 13-15
routers, 89-91
BGP, 233
ASs, 234-235
defaults, 238-239
IGP metric, 237
injecting into IGP, 234
Primary/Backup policy, 236-237
shorter paths than IGP, 238
transit routers, 238
border, 100
concentration, 254
IBGP (ASs), 235
neighbors (BGP4), 103
flip-flopping, 109
non-BGP, 233
ASs, 235
OSPF-generated defaults, 240-241
peers (BGP4), 103
RIP-generated defaults, 239
transit, 100
routes
aggregation, 157-159
attributes, 306
backdoors, 324-326
BGP (Border Gateway Protocol)
AS_path, 174
filtering, 169
injecting, 132-137
injecting dynamically, 315-322
injecting statically, 323
load balancing, 193, 201-203
NLRI, identifying, 172-274
ORIGIN, 137-139
peer groups, 178-180
redundancy, 193-203
route maps, 306-308
symmetry, 193, 201-203
BGP4
aggregation, 180-186
withdrawn, 115-116
dampening, 136, 289-290
defaults
dynamically learned, 368-369
statically set, 370-373
denying, 171
filtering, 306
AS_path, 310-311
NLRI, 308-310
flapping, 283
identifying, 171
AS_path, 174
BGP, based on NLRI, 174
NLRI, 172-173
instability, 283
backup links, 287
BGP, 288
CPU power, 285
hardware, 285
human error, 287
IGPs, 284
memory, 286
network upgrades, 286-287
software, 285
permitting, 171
routing
AS_path approach, 398-399
autonomous systems (AS), 95-96
multihomed nontransit, 98-99
multihomed transit, 100-101
stub, 97-98
backdoor protocols, 140-141
BGP, static versus dynamic, 139
BGP4, 101-102
KEEPALIVE messages, 104
message header format, 104-106
neighbor negotiation, 106
neighbors, 103
path vectors, 102
updates, 103
black holes, 69
aggregating, 70-72
community approach, 395-398
convergence, 92
default, 95-96
distance vector protocols, 92-93
dynamic, 95-96
EGP, 95
full, 204
less specific routes, 68
link state protocols, 93-94
longest match, 67
loops, 68
mobile networks, 139
NAPs, 13
partial, 204
pit buckets, 68
policy, 244-245
ASs defaults, 418-422
dialup, 247
drawbacks, 247-248
firewalls, 246
static, 95-96, 244-245
Routing Arbiter Database (RADB), 16
Routing Arbiter Database (Routing Registry), 31
routing domains (classless), 65
routing engineering team, 16
routing protocols, VLSM, 59
Routing Registries (RR), 30-31
Internetworking Routing Registries (IRR), 30-31
routing tables, 91
RR (Routing Registries), 30-31
RTA configuration
BGP attributes, 327
BGP peering session, 301-303
RTC configuration
BGP attributes, 328-329
BGP peering session, 304
RTD configuration
BGP attributes, 329
BGP peering session, 304-305
RTF configuration
BGP attributes, 327-328
BGP peering session, 303-305

S

security
firewalls, policy routing, 246
ISPs, 39
semidynamic (injecting routes BGP), 133-137
services (ISPs), 39
single provider
multihomed, 373
default, one primary, one backup, partial routing, 376-382
default only, one primary, one backup, 373-376
single-character patterns (AS_path), 175-176
single-homed, 66
addresses outside provider's space, 70
load balancing, 204-205
redundancy, 204-205
symmetry, 204-205
soft reconfiguration (BGP), 433-437
software, route instabilities, 285
SONET (Synchronous Optical Network), 18
speed (NAPs), 9
Sprint (NAPs), 9
static routing, 95-96, 244-245
versus dynamic, 139
statically injecting routes (BGP), 323
statically set defaults
BGP, 370-373
redundancy
BGP, 197-200
stub ASs, 97-98
subnet masks, 56
VLSM (Variable Length Subnet Masks), 57
subnetting
IP addresses, 55-57
Variable Length Subnet Masks (VLSM), 55-57
supernet masks, 64
support services (InterNIC), 28-29
symmetry (BGP), 193, 201-203
AS_path, 227-228
multihomed, 209
multihomed to different provider, 215-219
multihomed to single provider, 205-214
multiple providers, 223-228
private links, 219-223
single-homed, 204-205
synchronization, BGP peer sessions (ASs), 130-132

T

T1 lines, ISP prices, 40
T3 lines, ISP prices, 40
tables (routing), 91
templates (InterNIC), 24
Autonomous System numbers, 25
CIDR blocks, 24
contact registration, 24
domain names, 26
host registration, 25
IN-ADDR domain, 26
IP numbers, 25
topologies (fully meshed), 152
traffic
exchange aggreements (ISP backbones), 44
load balancing, 202
transit routers, 100
transitioning
NAPs from NSFNET, 10
regional networks, 19-20

U

unicast addresses, 79-80
unstable routes, 283
backup link overloads, 287
BGP, 288
route and cache invalidation, 288-289
route dampening, 289-290
CPU power, 285
hardware, 285
human error, 287
IGPs, 284
memory, 286
network upgrades, 286-287
software, 285
UPDATE message (BGP4), 113
update policies (peer groups), 312
updates (BGP4), 103
upgrades, route instabilities, 286-287

V

Variable Length Subnet Masks (VLSM), 55-58
vBNS (Backbone Network Service), 19
geopgraphical components, 18
NAPs, 18
NSFNET, 8
vBNS (Very High-Speed Backbone Network Service), 17
ATM (Asynchronous Transfer Mode), 18
communication centers, 17
SONET (Synchronous Optical Network), 18
Virtual Private Networks (VPN) (route reflectors), 275-277
VLSM (Variable Length Subnet Masks), 55-58
routing protocols, 59
VPN (Virtual Private Networks), 275-277

W-Z

WAIS (Wide Area Information Server), 24
WHOIS
InterNIC, 27-28
RIPE databases, 460-461
withdrawn routes (BGP4), 115-116
WWW (ISPs), 39


Table of Contents