Ch. 5 - Network Layer (Control Plane)

Question 1

What is OSPF?

Answer 1

Open Shortest Path First; intra-ISP routing protocol.

Question 2

What is BGP?

Answer 2

Border Gateway Protocol; inter-ISP routing protocol.

Question 3

What is SNMP?

Answer 3

Simple Network Management Protocol; network management standard.

Question 4

What is YANG?

Answer 4

Data modeling language for network configuration.

Question 5

What is NETCONF?

Answer 5

Network configuration protocol for managing devices.

Question 6

Per-router Control

Answer 6

Traditional method with local routing algorithms.

Question 7

Logically Centralized Control

Answer 7

SDN approach with remote controller managing routers.

Question 8

Link State Algorithm

Answer 8

Routing method using complete topology information.

Question 9

Distance Vector Algorithm

Answer 9

Routing method based on neighbor information exchange.

Question 10

Dijkstra’s Algorithm

Answer 10

Finds least-cost paths in a network graph.

Question 11

Link Cost

Answer 11

Cost associated with a direct link between routers.

Question 12

Graph Abstraction

Answer 12

Modeling network as nodes (routers) and edges (links).

Question 13

Routing Protocol Goal

Answer 13

Determine optimal paths through a network of routers.

Question 14

Message Complexity

Answer 14

Total messages exchanged during routing updates.

Question 15

Oscillations in Routing

Answer 15

Route instability due to changing link costs.

Question 16

Cost Definition

Answer 16

Determined by network operator; affects routing decisions.

Question 17

Routing Algorithm Classification

Answer 17

Categorizes algorithms based on information availability.

Question 18

Network Management

Answer 18

Processes for configuring and monitoring network devices.

Question 19

Routing Among ISPs

Answer 19

BGP handles routing between different Internet Service Providers.

Question 20

Intra-ISP Routing

Answer 20

OSPF manages routing within a single ISP.

Question 21

Control Plane Roadmap

Answer 21

Outline of topics in network layer control plane.

Question 22

Routing Path

Answer 22

Sequence of routers packets traverse to reach destination.

Question 23

Link State

Answer 23

Routing protocol that maintains a complete network map.

Question 24

Distance Vector

Answer 24

Routing protocol based on neighbor distance estimates.

Question 25

NETCONF/YANG

Answer 25

Protocols for network configuration and management.

Question 26

Bellman-Ford Equation

Answer 26

Calculates least-cost paths in distance vector routing.

Question 27

Dynamic Programming

Answer 27

Method used in Bellman-Ford for optimization.

Question 28

Convergence

Answer 28

When distance vector estimates stabilize.

Question 29

Local Link Cost Change

Answer 29

Change in cost of a direct link.

Question 30

DV Update Message

Answer 30

Message sent to update distance vector estimates.

Question 31

Distance Vector Example

Answer 31

Illustration of distance vector calculations.

Question 32

Iteration

Answer 32

Process of updating distance vectors repeatedly.

Question 33

Neighbor Notification

Answer 33

Informing neighbors of distance vector changes.

Question 34

Local Distance Vector

Answer 34

Node’s current estimate of distances to neighbors.

Question 35

Cost Calculation

Answer 35

Determining the least cost to reach a node.

Question 36

Convergence Time

Answer 36

Time taken for all routers to agree on routing.

Question 37

Count-to-Infinity Problem

Answer 37

Routing issue where incorrect cost circulates indefinitely.

Question 38

Link-State Protocol

Answer 38

Routing protocol where routers share complete network state.

Question 39

Routing Loop

Answer 39

Situation where packets circulate endlessly in the network.

Question 40

Administrative Autonomy

Answer 40

Control over routing policies by individual network admins.

Question 41

Path Vector Protocol

Answer 41

Routing protocol where paths to destinations are advertised.