What Are OSPF Packets Types
There are5 types of OSPF packets.
Beginning of all OSPF packets is specified by standard header of24 bytes.
A list of link state advertisements is used in dealing with all OSPF packet types.
Types of OSPF packets:1.
The Hello Packet : The hello packets are sent over a period of time on all interfaces for the purpose of establishing and maintaining neighbor relationships.
Hello packets are multicast on the networks having multicast capability, which enables discovery of neighboring routers dynamically.
The inhabitance of differences among hello packets can form neighbor relationships by agreeing certain parameters.2.
The Database Description Packet : At the time of adjacency is being initialized, these packets are exchanged.
These packets describe topological database contents.
The database may be described by using multiple packets.
A poll-response procedure is used for the description of multiple packets usage.
Among the routers, one is designated to be master, and the other a slave.
The Database Description packets are sent by the slave after sending the Database Description packets by the master.3.
The Link State Request packet : A router may find the parts of its topological database are out of date, after database description package exchange with a neighbouring router.
The Link State Request packet is utilized for requesting the pieces of the neighbour’s database which are more up to date.
There may be a need to utilize multiple Link State Request packets.4.
The Link State Update packets: The flooding of link state advertisements is implemented by these packets.
A collection of link state advertisements are carried by each Link Statement Update packet, one hop further from its origin.
A packed may be included by several link state advertisements.5.
The Link State Acknowledge packets: The reliability of flooding link state advertisement is made by explicitly acknowledging flooded advertisements.
The accomplishment of this acknowledgement is done through the sending and receiving of Link Sate Acknowledgement packets.
A single Link State Acknowledgement packet is used to acknowledge the multiple link state advertisements.