OSPF Area Concepts

Question 1

What makes OSPF highly scalable?

Answer 1

usage of OSPF areas

Question 2

What area needs to be present in each topology by default?

Answer 2

area 0, which serves as the core area through which all other OSPF areas interconnect

Question 3

What are the roles of OSPF area 0?

Answer 3

• Backbone Area
  
  • hierarchical area structure allows OSPF to scale effectively in large networks and helps in partitioning the network into manageable segments
• Interconnection
  
  • enables routers in one area to learn about routes in other areas without the need for direct physical connections between those areas
• Default Route Distribution
  
  • default route provides a way for routers within non-backbone areas to reach destinations outside the OSPF domain, such as the Internet
• Loop Prevention
  
  • uses the backbone area as a loop prevention mechanism

Question 4

What are the two main functions of OSPF area?

Answer 4

• reduce the number of redundant paths through a network
  
  • greatly reduces convergence time
• limit the propagation of LSAs based on their type
  
  • some LSAs stay within an area, while others are flooded to all areas

Question 5

Is it true that all routers know about the other routers and networks within the same area?

Answer 5

yes

Question 6

What are the different OSPF Area Types? (5)

Answer 6

1. Stub
2. Totally stubby
3. Totally no-so-stubby
4. Not-so-stubby
5. Normal

Question 7

What type of area is the backbone area 0?

Answer 7

normal area

Question 8

What is the main purpose of OSPF area?

Answer 8

limit the propagation of LSAs