Multicast address 224.0.0.5 confusion OSPF?

[llukman.halimi]

I am confused on the address 224.0.0.5 multicast address.
-Used to send OSPF messages to all OSPF routers on the same network. The AllSPFRouters address is used for Hello packets. The DR and BDR use this address to send Link State Update and Link State Acknowledgment packets.

I want to know when is it a hello packet and when is it used for LSA's..I know hello packets are sent in order to establish an adjacency with another router and to maintain a relationship with that router by sending hello packets back and forth...but I just don't know when is it meant to for hello packets and when is it meant for LSA updates....

sorry if I am not explaining it that well....just confused.

[Georg Pauwen]

Hello,

'Hello' packets are sent initially when establishing adjacenicies, and after that at specific intervals (10 seconds for broadcast and point-to-point networks, 30 seconds for nonbroadcast multi access networks).

'LSA' packets are sent every 30 minutes, and initially when establishing adjacencies.

Is that what you are asking ?

[ajay chauhan]

Hello packets and LSA's are two different thing . As mentioned by "gpauwen" 1st you form adjacencies by exchanging hello packets , once adjacencies are formed you exchange LSA's.

Hope this helps.

Ajay 

[Richard Burts]

If I am interpreting the original post correctly the confusion is that 224.0.0.5 is used for Hello packets and also is used for Link State Updates and the original poster wants to know when it is a Hello packet and when it is a Link State Update. It might help if we make the point that all OSPF routers use this multicast address to send Hello packets but that only the DR and/or BDR use this multicast address for Link State Updates. It might also help if we make the point that there is a field in the OSPF packet that distinguishes whether the packet is a Hello or is a Link State Update.

So all OSPF routers use this multicast address for Hello while only DR/BDR use this multicast for Link State Update. And any OSPF router which receives this multicast packet will look in the OSPF header to determine whether it is a Hello or is a Link State Update and then processes the packet appropriately.

HTH

Rick