Routing Fundamentals

Question 1

What is routing?

Answer 1

The process of forwarding packets between networks.

Question 2

What are the general rules of routing?

Answer 2

1. Routers will only use routes with reachable next hops
2. Routers will only use the best route
3. Routes must be believable and still active
4. Router will only accept routes that match it’s own active protocols

Question 3

What is a connected route?

Answer 3

The router has a network on it’s interface and is able to figure out what network is on the cable that’s connected to the interface

Question 4

What is a Static route?

Answer 4

A route that is manually setup within the router.

Question 5

What is a Dynamic Route?

Answer 5

A route that was learned through one of the routing protocols

Question 6

What is administrative distance?

Answer 6

The feature that routers use in order to select the best path when there are two or more different routes to the same destination from two different routing protocols also defines the reliability of a routing protocol

Question 7

What is the administrative distance range?

Answer 7

0-255

Question 8

What is the connected protocol administrative distance?

Answer 8

0

Question 9

What is the static route protocol administrative distance?

Answer 9

1

Question 10

What is the EIRGP(internal) protocol administrative distance?

Answer 10

90

Question 11

What is the OSPF protocol administrative distance?

Answer 11

110

Question 12

What is the IS-IS protocol administrative distance?

Answer 12

115

Question 13

What is the RIP protocol administrative distance?

Answer 13

120

Question 14

What is the EIRGP(EXTERNAL) protocol administrative distance?

Answer 14

170

Question 15

What is the IBGP/EBGP protocol administrative distance?

Answer 15

200/20

Question 16

What is the unreachable administrative distance?

Answer 16

255

Question 17

What is an Autonomous System?

Answer 17

Collection of networks under 1 administrative authority

Question 18

What is IGP?

Answer 18

Interior Gateway Protocol

Provides reachability information WITHIN an autonomous system

Question 19

What is EGP?

Answer 19

Exterior Gateway Protocol

Provides reachability information BETWEEN DIFFERENT autonomous systems

Question 20

What are the 4 categories of routing protocols?

Answer 20

Distance Vector - IGP

Link State - IGP

Advance Distance Vector(Hypbrid) - IGP

Path Vector - EGP

Question 21

What are the 4 routing update types?

Answer 21

Incremental Update - Only changes are sent in the update

Full update- Full routing table is sent in the update

Periodic Update - Sent in the specified time interval

Triggered update - Sent whenever change is detected

Triggered and Incremental are basically the same thing.

Question 22

What is a routing metric?

Answer 22

Metrics are used to determine whether one route should be chosen over another. The metric depends on the routing protocol architecture.

Rip Metric - Hop Count

OSPF Metric - Link Bandwidth

EIGRP - Composite formula utilizing link bandwidth and delay

Question 23

Where is basic info of a statis route?

Answer 23

1. Used in small networks
2. No dynamic fail over
3. Information on destination prefix and gateway are required

Question 24

What is a floating static route?

Answer 24

A manually set static route with a higher administrative distance than another more preferred route.

Command:

Router(config)#ip route

Question 25

What is Router on a stick?

Answer 25

Term frequently used to describe a setup up that consists of a router and switch connected using one Ethernet link configured as an 802.1q trunk link. In this setup, the switch is configured with multiple VLANs and the router performs all routing between the different networks/VLANs.

Question 26

What do you have to do to a switch for it to route?

Answer 26

Enable routing on the switch Switch(config)#ip routing

Question 27

What are the characteristics of RIPv2?

Answer 27

IGP/ Distance Vector - no neighbor relations Metric = Hop Count Capable of load balacing 6 equal cost paths Sends out routing updates every 30 seconds

Question 28

What multicast addresses does RIP utilize for IPv4 and IPv6?

Answer 28

IPv4 - 224.0.0.9 IPv6 - FF02::9

Question 29

What are the IGP dynamic routing configuration steps?

Answer 29

1. Makes sure there is at least one functional interface with an i[ address on the device. 2. Enable routing protocol 3. Define networks for which the routing protocol will be active 4. Enable authentication for the routing protocol (optional)

Question 30

What is the command for a IPv6 address?

Answer 30

Router(config-if)#i[v6 address

/

Question 31

Is IPv6 enabled by default on routers or multi-layer switches?

Answer 31

No Use the command Router(config)# ipv6 unicast-routing Permits router to send ICMPv6 Router Advertisements Allows IPv6 routing between connected interfaces Allows operation of IPv6 routing protocols.

Question 32

How do you set a IPv6 static route?

Answer 32

Router(config)#ipv6 route

Question 33

How do you configure a default IPv6 Route?

Answer 33

Router(config)# ipv6 route ::/0 2001:aa:bb:cc::77