Regarding OSPF LSA Types

[skraon001]

Hi all,,

Can anyone please explain me the OSPF LSA types applicable for Cisco Devices,,

1.Router LSA

2.Network LSA

3.Summary link LSA (Generated by ABR sends update to opposite area)

4.Summary Link LSA (Generated by ABR sends updates to opposite area how to reach ASBR)

5.External type LSA (ASBR sends updates about external routes)

and i came to know there are 3 more LSA's applicable for cisco devices.

Can any one help me with this. if u know any link for studying please suggest.

Thanks in advance

Srikanth

[Georg Pauwen]

Hello Srikanth,

have a look at the link below:

https://networklessons.com/ospf/ospf-lsa-types-explained/

[Spooster IT Services]

Hello Srikanth, 

OSPF LSA Types

LSA Type        Common Name                     Description
    1                        Router                          One per router per area, listing the router’s RID and
                                                                   all interface IP addresses in that area. Represents stub
                                                                   networks as well. Flooded only within its area of origin.

    2                       Network                        One per transit network. Created by the DR on the
                                                                   subnet, and represents the subnet and the router
                                                                   interfaces connected to the subnet. Flooded only within
                                                                   its area of origin.

    3                     Net Summary                  Created by ABRs to represent networks present in one
                                                                   area when being advertised into another area. Defines
                                                                   the subnets in the origin area, and cost, but no topology
                                                                   data. Flooded only within its area of origin; reoriginated
                                                                   on ABRs.

    4                   ASBR Summary                Like a type 3 LSA, except it advertises a host route
                                                                   used to reach an ASBR. Flooded only within its area of                                                                                                                                                  origin; reoriginated on ABRs.

    5                     AS External                     Created by ASBRs for external routes injected into                                                                                                                                                          OSPF. Flooded to all regular areas.