We know that the Type-1 LSA describes the link type connected to the router, the neighbor router and the subnet […]
Archive for ‘OSPF Routing Protocol’
OSPF DR vs ISIS DIS, and Multiaccess Subnet Number
Like with DR (Designated Router) on OSPF, on broadcast multi-access, IS-IS elects a designated intermediate system (DIS) but keep in […]
OSPF ABR as a DR or Drother?
Is there a recommendation to ensure that the ABR will be the DR?The answer is NO. There is no relation […]
RFC 3101 The OSPF Not-So-Stubby Area (NSSA) Option Summarized
1. NSSAs are similar to the existing OSPF stub area configuration option but have the additional capability of importing AS […]
Why In DMVPN Phase 2 it is recommended to use OSPF Broadcast Network Type instead of Point to MultiPoint?
In DMVPN Phase 2 and in order to achieve spoke to spoke connectivity, when using OSPF Routing Protocol, the recommendation […]
What is OSPF Type-4 LSA?
This Type LSA has always been confusing to many people. This LSA describes the metric that the ABR uses to […]
Why an NSSA ABR does not inject a default route automatically into NSSA unlike with stub area ?
Why an NSSA ABR does not inject a default route automatically into NSSA unlike with stub area ? In this […]
OSPFv3 Link-State Database In-Depth Lecture
Basic configuration of all routers: R1: ipv6 unicast-routing ! interface FastEthernet0/0 ipv6 address 2012:12::1/64 ipv6 enable ospfv3 1 ipv6 area […]
Why the P-bit must be cleared in the Type-7 default route by an NSSA ABR?
When an NSSA ABR originates a Type-7 default route, the P-bit must be cleared in order to tell to other […]
OSPF Database Discrepancy
You set up a VPN MPLS with your service provider in order to connect your central site to your remote […]