What is the use of stub area?
What is the use of stub area?
Stub area, also called stub area, the so-called stub area, means that the area does not accept any external routes of non-OSPF network, if it wants to reach those external routes, only Need to send it through the default route. This area supports 1, 2, and 3 LSAs.
Why we need stub area in OSPF?
To control the advertisement of external routes into an area, OSPF uses stub areas. By designating an area border router (ABR) interface to the area as a stub interface, you suppress external route advertisements through the ABR.
What is stub area in CCNA?
Stub Area is the area that do not accept the External LSAs(Type 5). Stub Areas accept the summary LSAs Type 3 beside the Default Route from the Backbone Area. They also do not accept Type 4 LSAs. As you can see, Type 3, Type 4 LSAs and Default Route is in the routing table.
What is a stub network in OSPF?
A stub network is a network that contains only a single router – its gateway to the rest of the topology. Typically, all Ethernet interfaces where only end stations are connected are considered as stub networks by OSPF.
What is stub and NSSA?
An NSSA is a bit like a stub as far as the internal OSPF topology is concerned, but it is allowed to connect to the outside world. In other words, it is allowed to have an ASBR border router. Imagine you had a branch office that had an external link, say, to the Internet.
What are OSPF areas?
By definition an OSPF area is a collection of networks, not a collection of routers. A backbone network segment is an IP subnet that belongs to the area identified by 0.0. 0.0. Areas that are not physically connected to the backbone are logically connected by a backbone ABR using an OSPF virtual link.
What is stub?
A stub autonomous system that is connected to only one other autonomous system, through which it gains access to the Internet. This is also called a stub AS, which characterize the great majority of AS connected to the Internet.
What is a NSSA area?
NSSA (Not so stubby area) is an OSPF area type that allows the injection of external routes into the stub area by using a special LSA type called LSA type 7. This LSA type 7 is converted into an LSA type 5 when it leaves the NSSA area.
What are the different types of stub areas?
Show below is a list of the different type of stub area’s and their properties; Stub Area – An area that has a single exit point and blocks type 5/7 LSA types and receives type 3/4 LSA’s with a default route (0.0.0.0/0) This type of stub area is an IETF standard.
What is a stub area in OSPF router?
Stub Area – An area that has a single exit point and blocks type 5/7 LSA types and receives type 3/4 LSA’s with a default route (0.0.0.0/0) This type of stub area is an IETF standard. To configure an Area as a stub you’d execute the area # stub in OSPF router configuration mode on the ABR.
Can a backbone area be a stub area?
Stub areas cannot be used as a transit area for virtual links. An ASBR cannot be internal to a stub area. OSPF allows certain areas to be configured as stub areas, but the backbone area cannot be a stub area. LSA Types 4 and 5 are not allowed in a stub area.
How to configure area 3 as a stub?
When configuring an area stub type the command is executed on the ABR, however when you specify an area as a stub on the ABR, all routers in that area must have be configured as a stub by using the area # stub In this lab you will configure and verify area 3 as a stub area and totally stubby area.