simple question on OSPF: contents of the OSPF Hello message

aocferreiraaocferreira Member Posts: 50 ■■□□□□□□□□
Hi guys,

According to cisco press book, below items are present in OSPF hello messages:

■ OSPF Router ID
■ Stub area flag
■ Plus the following interface-specific settings:
■ Hello interval
■ Dead Interval
■ Subnet mask
■ List of neighbors reachable on the interface
■ Area ID
■ Router priority
■ Designated Router (DR) IP address
■ Backup DR (BDR) IP address
■ Authentication digest

What do they mean with 'list of neighbors reachable on the interface' ?
If R1 sends hello packet to R2 through S0/0, only neighbor on that interface is R2... or it will be...

Am I getting this right?

Comments

  • networker050184networker050184 Mod Posts: 11,962 Mod
    Yep pretty much. But there are instances when a router will have multiple neighbors out of a single interface.
    An expert is a man who has made all the mistakes which can be made.
  • aocferreiraaocferreira Member Posts: 50 ■■□□□□□□□□
    You are talking about frame relay topologies, for example? Yea it makes sense...

    It was just to confirm as it was not making much sense to me that sentence :)

    Thanks!
  • networker050184networker050184 Mod Posts: 11,962 Mod
    Not only frame relay, but also an ethernet segment which is much more common.
    An expert is a man who has made all the mistakes which can be made.
  • KoryKory Member Posts: 43 ■■□□□□□□□□
    The other purpose of the field is to trigger a state change in the relationship. Because, when the router sees its own address in that neighbor field, it moves to 2-way state.
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