Ccnp Interview questions

• Postal address:It has three components called state, city, and street that are used to deliver mail.A mail can be delivered to the next post office based on only the City, state and street information.
• Telephone number: It has an area code and exchange. It is delivered at the core layer based on the area code.

• Routing : It moves a letter or telephone call to the access layer.
• Switching:The final delivery is made by switching and the switching decision is made on the part of the address that isn’t used in routing.

• Postal system :In the postal system, the core layer is only information which is required to make a routing decision in the city or state information.
  We can see some specific street numbers and names hidden because the core layer doesn’t require them.
• Telephone system :In a telephone system, at the core layer, the area code is used to make the routing decision.The specific last four digit of the phone numbers are hidden because the core layer doesn’t require them.

• Street number and name are the components of access layer.
• The city name is the component of distribution layer.
• The state name is the component of the core layer.

• Classful: Classful routing protocols do not advertise the subnet mask information. For the Classful protocol, the subnets being used must be of the same length for the major network number. It can’t support discontiguous network prefixes.
• Classless: The protocol of Classless routing advertise is the subnet mask information along with the network prefixes.

• Passive state: The passive state means that the router has a successor for a route.
• Active state: The active state means that a router does not have a successor for a route and is sending queries to the neighbor to receive the information about the route.

• OSPF intra-area
• inter-area routes
• and also a default route.

The external routes are not advertised in this area.

• OSPF intra-area, inter-area routes and also a default route.
• The External routes from ASBRs are converted to N1 and N2 routes.

External routes from ABRs are blocked.

• ABR
• Internal router
• ASBR

• Intra-area
• Inter-area
• E1
• E2
• N1
• N2

• E1 OSPF route :The E1 OSPF route contains the OSPF cost to reach ASBR and the cost from ASBR to the external route.
• E2 OSPF route : The E2 route contains the cost from ASBR to the external route only.

• OSPF : The OSPF has area 0 or backbone area.
  All the non-zero areas must be connected through a virtual link or a router.
• IS-IS :It has a backbone area which is made up of a contiguous chain of Level 2 capable routers.

• Well-known mandatory
• Well-known discretionary
• Optional transitive
• Optional nontransitive