CC325 Taller de Redes Avanzadas

OSPF de Área Única.

Marco Teórico:

OSPF (Open Shortest Path First) Abrir la Ruta mas Corta Primero.
OSPF es un protocolo de direccionamiento de tipo enlace-estado, desarrollado para las redes IP y basado en el algoritmo de primera vía más corta (SPF). OSPF es un protocolo de gateway interior (IGP).

En una red OSPF, los direccionadores o sistemas de la misma área mantienen una base de datos de enlace-estado idéntica que describe la topología del área. Cada direccionador o sistema del área genera su propia base de datos de enlace-estado a partir de los anuncios de enlace-estado (LSA) que recibe de los demás direccionadores o sistemas de la misma área y de los LSA que él mismo genera. El LSA es un paquete que contiene información sobre los vecinos y los costes de cada vía. Basándose en la base de datos de enlace-estado, cada direccionador o sistema calcula un árbol de extensión de vía más corta, siendo él mismo la raíz, utilizando el algoritmo SPF.
Las ventajas principales de OSPF son las siguientes:
En comparación con los protocolos de direccionamiento de distancia-vector como el protocolo de información de direccionamiento (RIP), OSPF es más adecuado para servir entre redes heterogéneas de gran tamaño.
OSPF puede recalcular las rutas en muy poco tiempo cuando cambia la topología de la red.
Con OSPF, puede dividir un sistema autónomo (AS) en áreas y mantenerlas separadas para disminuir el tráfico de direccionamiento de OSPF y el tamaño de la base de datos de enlace-estado de cada área.
OSPF proporciona un direccionamiento multivía de coste equivalente. Se pueden añadir rutas duplicadas a la pila TCP utilizando saltos siguientes distintos.

Objetivo de la Practica.
Esta practica tiene como objetivo la implementación del protocolo dinámico OSPF de esta manera poder ver sus características en la practica.

Armado de la Maqueta:

Como siempre comenzamos configurando la Interfaz y el puerto serial.

1. Armar la maqueta propuesta configurando solo interfaces ethernet y serial. Note que la maqueta propuesta utiliza VLSM

2. Verificar conectividad con PING desde el Router hacia PC y Router vecinos.

3. Habilite OSPF de área O

R2(config)#router ospf 10

R2(config-router)#network 200.210.221.0 0.0.0.255 area 0

R2(config-router)#network 200.210.222.128 0.0.0.3 area 0

R2(config-router)#network 200.210.222.132 0.0.0.3 area 0

R2(config-router)#end

4. Verificar el anuncio de redes con "show ip route"

Router#show ip route

Codes: L - local, C - connected, S - static, 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

i - IS-IS, su - IS-IS summary, L1 - IS-IS level-1, L2 - IS-IS level-2

ia - IS-IS inter area, * - candidate default, U - per-user static route

o - ODR, P - periodic downloaded static route, H - NHRP, l - LISP

a - application route

+ - replicated route, % - next hop override

Gateway of last resort is not set

O 200.210.220.0/24 [110/129] via 200.210.222.133, 00:03:13, Serial0/0/1

O 200.210.221.0/24 [110/65] via 200.210.222.133, 00:09:23, Serial0/0/1

200.210.222.0/24 is variably subnetted, 5 subnets, 3 masks

C 200.210.222.0/25 is directly connected, GigabitEthernet0/1

L 200.210.222.1/32 is directly connected, GigabitEthernet0/1

O 200.210.222.128/30

[110/128] via 200.210.222.133, 00:03:23, Serial0/0/1

C 200.210.222.132/30 is directly connected, Serial0/0/1

L 200.210.222.134/32 is directly connected, Serial0/0/1

Router#

5. Conteste las siguientes preguntas:

*¿Cuantas redes aparecen en la tabla de enrutamiento?

*¿Cuantas deberían de aparecer?

6. Verifique estatus de OSPF

*show ip ospf

Router#show ip ospf

Routing Process "ospf 1" with ID 200.210.222.1

Start time: 00:07:32.828, Time elapsed: 00:35:42.156

Supports only single TOS(TOS0) routes

Supports opaque LSA

Supports Link-local Signaling (LLS)

Supports area transit capability

Supports NSSA (compatible with RFC 3101)

Event-log enabled, Maximum number of events: 1000, Mode: cyclic

Router is not originating router-LSAs with maximum metric

Initial SPF schedule delay 5000 msecs

Minimum hold time between two consecutive SPFs 10000 msecs

Maximum wait time between two consecutive SPFs 10000 msecs

Incremental-SPF disabled

Minimum LSA interval 5 secs

Minimum LSA arrival 1000 msecs

LSA group pacing timer 240 secs

Interface flood pacing timer 33 msecs

Retransmission pacing timer 66 msecs

Number of external LSA 0. Checksum Sum 0x000000

Number of opaque AS LSA 0. Checksum Sum 0x000000

Number of DCbitless external and opaque AS LSA 0

Number of DoNotAge external and opaque AS LSA 0

Number of areas in this router is 1. 1 normal 0 stub 0 nssa

--More-- Number of areas transit capable is 0

External flood list length 0

IETF NSF helper support enabled

Cisco NSF helper support enabled

Reference bandwidth unit is 100 mbps

Area BACKBONE(0) (Inactive)

Number of interfaces in this area is 2

Area has no authentication

SPF algorithm last executed 00:00:26.424 ago

SPF algorithm executed 2 times

Area ranges are

Number of LSA 1. Checksum Sum 0x0074CA

Number of opaque link LSA 0. Checksum Sum 0x000000

Number of DCbitless LSA 0

Number of indication LSA 0

Number of DoNotAge LSA 0

Flood list length 0

*show ip ospf neighbor

Router#show ip ospf neighbor interface

GigabitEthernet0/1 is up, line protocol is up

Internet Address 200.210.222.1/25, Area 0, Attached via Network Statement

Process ID 1, Router ID 200.210.222.1, Network Type BROADCAST, Cost: 1

Topology-MTID Cost Disabled Shutdown Topology Name

0 1 no no Base

Transmit Delay is 1 sec, State DR, Priority 1

Designated Router (ID) 200.210.222.1, Interface address 200.210.222.1

No backup designated router on this network

Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5

oob-resync timeout 40

Hello due in 00:00:02

Supports Link-local Signaling (LLS)

Cisco NSF helper support enabled

IETF NSF helper support enabled

Index 2/2, flood queue length 0

Next 0x0(0)/0x0(0)

Last flood scan length is 0, maximum is 0

Last flood scan time is 0 msec, maximum is 0 msec

Neighbor Count is 0, Adjacent neighbor count is 0

Suppress hello for 0 neighbor(s)

Serial0/0/1 is up, line protocol is up

Internet Address 200.210.222.134/30, Area 0, Attached via Network Statement

Process ID 1, Router ID 200.210.222.1, Network Type POINT_TO_POINT, Cost: 64

--More-- Topology-MTID Cost Disabled Shutdown Topology Name

--More-- 0 64 no no Base

--More-- Transmit Delay is 1 sec, State POINT_TO_POINT

--More-- Timer intervals configured, Hello 10, Dead 40, Wait 40, Retransmit 5

--More-- oob-resync timeout 40

--More-- Hello due in 00:00:01

--More-- Supports Link-local Signaling (LLS)

--More-- Cisco NSF helper support enabled

--More-- IETF NSF helper support enabled

--More-- Index 1/1, flood queue length 0

--More-- Next 0x0(0)/0x0(0)

--More-- Last flood scan length is 1, maximum is 1

--More-- Last flood scan time is 0 msec, maximum is 0 msec

--More-- Neighbor Count is 1, Adjacent neighbor count is 1

--More-- Adjacent with neighbor 200.210.222.133

--More-- Suppress hello for 0 neighbor(s)

Router#

*show ip ospf interface

Router#show ip ospf interface database rpo outer

OSPF Router with ID (200.210.222.1) (Process ID 1)

Router Link States (Area 0)

LS age: 621

Options: (No TOS-capability, DC)

LS Type: Router Links

Link State ID: 200.210.222.1

Advertising Router: 200.210.222.1

LS Seq Number: 8000000B

Checksum: 0x2A70

Length: 60

Number of Links: 3

Link connected to: a Stub Network

(Link ID) Network/subnet number: 200.210.222.0

(Link Data) Network Mask: 255.255.255.128

Number of MTID metrics: 0

TOS 0 Metrics: 1

Link connected to: another Router (point-to-point)

(Link ID) Neighboring Router ID: 200.210.222.133

--More-- (Link Data) Router Interface address: 200.210.222.134

--More-- Number of MTID metrics: 0

--More-- TOS 0 Metrics: 64

--More--

Link connected to: a Stub Network

(Link ID) Network/subnet number: 200.210.222.132

(Link Data) Network Mask: 255.255.255.252

Number of MTID metrics: 0

TOS 0 Metrics: 64

LS age: 439

Options: (No TOS-capability, DC)

LS Type: Router Links

Link State ID: 200.210.222.129

Advertising Router: 200.210.222.129

LS Seq Number: 80000002

Checksum: 0x1618

Length: 60

Number of Links: 3

Link connected to: another Router (point-to-point)

(Link ID) Neighboring Router ID: 200.210.222.133

(Link Data) Router Interface address: 200.210.222.129

Number of MTID metrics: 0

TOS 0 Metrics: 64

--More--

Link connected to: a Stub Network

(Link ID) Network/subnet number: 200.210.222.128

(Link Data) Network Mask: 255.255.255.252

Number of MTID metrics: 0

TOS 0 Metrics: 64

Link connected to: a Stub Network

(Link ID) Network/subnet number: 200.210.220.0

(Link Data) Network Mask: 255.255.255.0

Number of MTID metrics: 0

TOS 0 Metrics: 1

LS age: 439

Options: (No TOS-capability, DC)

LS Type: Router Links

Link State ID: 200.210.222.133

Advertising Router: 200.210.222.133

LS Seq Number: 8000000A

Checksum: 0xD732

Length: 84

Number of Links: 5

--More--

--More-- Link connected to: a Stub Network

--More-- (Link ID) Network/subnet number: 200.210.221.0

(Link Data) Network Mask: 255.255.255.0

Number of MTID metrics: 0

TOS 0 Metrics: 1

Link connected to: another Router (point-to-point)

(Link ID) Neighboring Router ID: 200.210.222.1

(Link Data) Router Interface address: 200.210.222.133

Number of MTID metrics: 0

TOS 0 Metrics: 64

Link connected to: a Stub Network

(Link ID) Network/subnet number: 200.210.222.132

(Link Data) Network Mask: 255.255.255.252

Number of MTID metrics: 0

TOS 0 Metrics: 64

Link connected to: another Router (point-to-point)

(Link ID) Neighboring Router ID: 200.210.222.129

(Link Data) Router Interface address: 200.210.222.130

Number of MTID metrics: 0

TOS 0 Metrics: 64

--More-- Link connected to: a Stub Network

--More-- (Link ID) Network/subnet number: 200.210.222.128

--More-- (Link Data) Network Mask: 255.255.255.252

Number of MTID metrics: 0

TOS 0 Metrics: 64

Router#

sábado, 9 de diciembre de 2017