Topic 3 - Routing Technologies

Question 1

IGP (Interior Gateway Protocol)

Answer 1

The protocol responsible for exchanging routing information within an AS.

Question 2

EGP (Exterior Gateway Protocol)

Answer 2

A routing protocol that can span multiple, autonomous networks

Question 3

Key difference between IGP and EGP?

Answer 3

IGP is protocol WITHIN an AS

BGP is protocol BETWEEN AS’s

Question 4

Routing protocols? and which are IGP and BGP?

Answer 4

Distance Vector (IGPs)
Link-State (IGPs)
Advanced Distance Vector (Hybrid) (IGPs)
Path Vector (EGP)

Question 5

Distance Vector Routing Explain

Answer 5

Each router passes a copy of its routing table to its adjacent neighbors.
The neighbor adds the route to its own table, incrementing the metric to reflect the extra distance to the end network. The distance is given as a hop count; the vector component specifies the address of
the next hop.

Question 6

Examples of Distance Vector Routing Protocols?

Answer 6

RIP V1 and V2

EIGRP

Question 7

Link State Explain

Answer 7

Requires neighbors
Periodic Hello’s between neighbors
Regenerate LSAs (Link State Advertisements) after defined interval
Complete visibility of entire topology for directly-connected areas

Question 8

what is the default router priority with HSRP?

Answer 8

100

Question 9

3 types of FHRP (First Hop Redundancy Protocol)

Answer 9

1. HSRP (Hot Standby Router Protocol)
2. VRRP (Virtual Router Redundancy Protocol)
3. GLBP (Gateway Load Balancing Protocol)

Question 10

What RFC is HSRP defined in?

Answer 10

RFC 2281

Question 11

In HSRP, the active router responds to default gateway ARP requests with…

Answer 11

virtual router MAC address

Question 12

In IPv6, it is best practice for your default gateway to be what type of address?

Answer 12

Link-Local

Question 13

What does EIGRP use as its metrics by default?

Answer 13

Bandwidth and Delay

Question 14

What does EIGRP use to prevent loops?

Answer 14

Split Horizon

Question 15

EIGRP uses 2 types of load balancing?

Answer 15

Equal-cost load balancing

Unequal-cost load balancing

Question 16

general characteristics of a link-state protocol

Answer 16

• More scalable
• Each router has a full topology
• Updates sent when topology change occurs
• Respond quickly to topology changes
• More info communicated between routers than Distance Vector
• Only type of IGP found in large network environments

Question 17

What is default reference bandwidth in OSPF?

Answer 17

100 Mbps

Question 18

List the 4 OSPF router roles

Answer 18

1. Backbone
2. Internal
3. ABRs (Area Border Router)
4. ASBRs (Autonomous System Boundary Router)

Question 19

How is the Designated Router chosen in OSPF?

Answer 19

Router_ID, which is the highest IP address of the loopback interfaces. If no loopbacks, then chooses highest IP address of the interfaces

Question 20

How does OPSFv3 communicate?

Answer 20

It uses IPv6 multicast addresses

Question 21

What do FHRP do?

Answer 21

The FHRP provides default gateway redundancy

Question 22

Which EIGRP information is held in RAM and maintained through the use of Hello and update packets?

Answer 22

Neighbor table

Topology table

Question 23

Where are EIGRP successor routes stored?

Answer 23

Neighbor table

Topology table

Question 24

Which command will display all the EIGRP feasible successor routes known to a router?

Answer 24

show ip eigrp topology

Question 25

What is considered to be a feasible route?

Answer 25

Any secondary route to a remote network

Question 26

What does the variance command do in EIGRP?

Answer 26

Provides unequal load balancing

Question 27

For EIGRP to form an adjacency with a neighbor, the _________ numbers must match, and the metric _- _________ must match as well.

Answer 27

AS

K-values

Question 28

What routes are the routes picked from the topology table as the best route to a remote network

Answer 28

Successor

Question 29

The topology table contains any route that is not as good as the successor route and is considered a __________ successor, or ___________ route

Answer 29

feasible

backup

Question 30

In order for two OSPF routers to form an adjacency they…

Answer 30

• Must be in the same area
• Must be in the same subnet
• Hello and dead timers must match

Question 31

Default Administrative Distance

Answer 31

Connected: 0
Static: 1
eBGP
EIGRP: 90
OSPF: 110
RIP:120

Question 32

what is Metric Value?

Answer 32

a value that allow the the protocol to determine the best routes within the protocol

Question 33

What does Split Horizon method do?

Answer 33

Prevent loop

Question 34

Route Poisoning

Answer 34

a method to prevent a router from sending packets through a route that has become invalid within computer networks

Question 35

Router on a stick?

Answer 35

Router on a stick is a means of connecting to two or more subnets via a single physical Layer 3 interface using subinterfaces.

Question 36

static routing and dynamic routing

Answer 36

Dynamic routing protocols automatically detect and adapt to network changes whereas Static routing requires manual intervention to adjust to network changes.

Question 37

Administrative Distance of Static routes

Administrative Distance of Dynamic routes

Answer 37

Static - default admin distance of 1

Dynamic - higher than 1 and dependent on the protocol

Question 38

What does Link state use as its metrics by default?

Answer 38

Cost

Question 39

What are Interior Routing protocols?

Answer 39

RIP, EIGRP, OSPF, IS-IS

Question 40

What are exterior routing protocol?

Answer 40

BGP, EGP and IDRP

Question 41

Commands to shows routes learned via OSPF only?

Answer 41

show ip route ospf

Question 42

Shows all the information contained in the LSDB?

Answer 42

show ip ospf database